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Deveshwar N, Yao J, Han M, Dwork N, Shen X, Ljungberg E, Caverzasi E, Cao P, Henry R, Green A, Larson PEZ. Quantification of the in vivo brain ultrashort-T 2* component in healthy volunteers. Magn Reson Med 2024; 91:2417-2430. [PMID: 38291598 DOI: 10.1002/mrm.30013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 12/14/2023] [Accepted: 12/29/2023] [Indexed: 02/01/2024]
Abstract
PURPOSE Recent work has shown MRI is able to measure and quantify signals of phospholipid membrane-bound protons associated with myelin in the human brain. This work seeks to develop an improved technique for characterizing this brain ultrashort-T 2 ∗ $$ {\mathrm{T}}_2\ast $$ component in vivo accounting forT 1 $$ {\mathrm{T}}_1 $$ weighting. METHODS Data from ultrashort echo time scans from 16 healthy volunteers with variable flip angles (VFA) were collected and fitted into an advanced regression model to quantify signal fraction, relaxation time, and frequency shift of the ultrashort-T 2 ∗ $$ {\mathrm{T}}_2\ast $$ component. RESULTS The fitted components show intra-subject differences of different white matter structures and significantly elevated ultrashort-T 2 ∗ $$ {\mathrm{T}}_2\ast $$ signal fraction in the corticospinal tracts measured at 0.09 versus 0.06 in other white matter structures and significantly elevated ultrashort-T 2 ∗ $$ {\mathrm{T}}_2\ast $$ frequency shift in the body of the corpus callosum at- $$ - $$ 1.5 versus- $$ - $$ 2.0 ppm in other white matter structures. CONCLUSION The significantly different measured components and measuredT 1 $$ {\mathrm{T}}_1 $$ relaxation time of the ultrashort-T 2 ∗ $$ {\mathrm{T}}_2\ast $$ component suggest that this method is picking up novel signals from phospholipid membrane-bound protons.
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Affiliation(s)
- Nikhil Deveshwar
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
- UC Berkeley - UCSF Graduate Program in Bioengineering, San Francisco, California, USA
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, California, USA
| | - Jingwen Yao
- UC Berkeley - UCSF Graduate Program in Bioengineering, San Francisco, California, USA
| | - Misung Han
- UC Berkeley - UCSF Graduate Program in Bioengineering, San Francisco, California, USA
| | - Nicholas Dwork
- Departments of Biomedical Informatics and Radiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Xin Shen
- UC Berkeley - UCSF Graduate Program in Bioengineering, San Francisco, California, USA
| | - Emil Ljungberg
- Department of Medical Radiation Physics, Lund University, Lund, Sweden
| | - Eduardo Caverzasi
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Peng Cao
- Department of Diagnostic Radiology, Hong Kong University, Hong Kong, China
| | - Roland Henry
- Department of Neurology, University of California, San Francisco, San Francisco, California, USA
| | - Ari Green
- Department of Neurology, University of California, San Francisco, San Francisco, California, USA
| | - Peder E Z Larson
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
- UC Berkeley - UCSF Graduate Program in Bioengineering, San Francisco, California, USA
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Jerban S, Ma Y, Wei Z, Shen M, Ibrahim Z, Jang H, Lu P, Chang DG, Woods G, Chung CB, Chang EY, Du J. Ultrashort echo time MRI detects significantly lower collagen but higher pore water in the tibial cortex of female patients with osteopenia and osteoporosis. J Bone Miner Res 2024:zjae053. [PMID: 38591788 DOI: 10.1093/jbmr/zjae053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Ultrashort echo time (UTE) MRI can quantify the major proton pool densities in cortical bone, including total (TWPD), bound (BWPD), and pore water (PWPD) proton densities, as well as the macromolecular proton density (MMPD), associated with the collagen content, which is calculated using macromolecular fraction (MMF) from UTE magnetization transfer (UTE-MT) modeling. This study aimed to investigate the differences in water and collagen contents in tibial cortical bone, between female osteopenia (OPe) patients, osteoporosis (OPo) patients, and young participants (Young). Being postmenopausal and above 55 years old were the inclusion criteria for OPe and OPo groups. The tibial shaft of fourteen OPe (72.5 ± 6.8 years old), thirty-one OPo (72.0 ± 6.4 years old), and thirty-one young subjects (28.0 ± 6.1 years old) were scanned using a knee coil on a clinical 3 T scanner. Basic UTE, inversion recovery UTE, and UTE-MT sequences were performed. Investigated biomarkers were compared between groups using Kruskal-Wallis test. Spearman's correlation coefficients were calculated between the total hip dual-energy x-ray absorptiometry (DXA) T-score and UTE-MRI results. MMF, BWPD, and MMPD were significantly lower in OPo patients than in the young group. Whereas T1, TWPD, and PWPD were significantly higher in OPo patients. The largest OPo/Young average percentage differences were found in MMF (41.9%), PWPD (103.5%), and MMPD (64.0%). PWPD was significantly higher (50.7%), while BWPD was significantly lower (16.4%) in OPe than the Young group on average. MMF was found to be significantly lower (27%) in OPo patients compared with OPe group. T1, MMF, TWPD, PWPD, and MMPD values significantly correlated with the total hip DXA T-scores (provided by the patients and only available for OPe and OPo patients). DXA T-score showed the highest correlations with PWPD (R = 0.55) and MMF (R = 0.56) values. TWPD, PWPD, and MMF estimated using the UTE-MRI sequences were recommended to evaluate individuals with OPe and OPo.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, San Diego, CA, United States
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, CA, United States
| | - Zhao Wei
- Department of Radiology, University of California, San Diego, CA, United States
| | - Meghan Shen
- Department of Radiology, University of California, San Diego, CA, United States
| | - Zubaid Ibrahim
- Department of Radiology, University of California, San Diego, CA, United States
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA, United States
| | - Pengzhe Lu
- Research Service, VA San Diego Healthcare System, San Diego, CA, United States
- Department of Neurosciences, University of California, San Diego, CA, United States
| | - Douglas G Chang
- Department of Orthopaedic Surgery, University of California, San Diego, CA, United States
| | - Gina Woods
- Department of Medicine, University of California, San Diego, San Diego, CA, United States
| | - Christine B Chung
- Department of Radiology, University of California, San Diego, CA, United States
- Research Service, VA San Diego Healthcare System, San Diego, CA, United States
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA, United States
- Research Service, VA San Diego Healthcare System, San Diego, CA, United States
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA, United States
- Research Service, VA San Diego Healthcare System, San Diego, CA, United States
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Jerban S, Moazamian D, Ma Y, Afsahi AM, Dwek S, Athertya J, Malhi B, Jang H, Woods G, Chung CB, Du J, Chang EY. Fast dual-echo estimation of apparent long T2 fraction using ultrashort echo time magnetic resonance imaging in tibialis tendons and its osteoporosis-related differences in women. Quant Imaging Med Surg 2024; 14:3146-3156. [PMID: 38617168 PMCID: PMC11007502 DOI: 10.21037/qims-23-1341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/09/2024] [Indexed: 04/16/2024]
Abstract
Background Tendon and bone comprise a critical interrelating unit. Bone loss, including that seen with osteopenia (OPe) or osteoporosis (OPo), may be associated with a reduction in tendon quality, though this remains incompletely investigated. Clinical magnetic resonance imaging (MRI) sequences cannot directly detect signals from tendons because of the very short T2. Clinical MRI may detect high-graded abnormalities by changes in the adjacent structures like bone. However, ultrashort echo time MRI (UTE-MRI) can capture high signals from all tendons. To determine if the long T2 fraction, as measured by a dual-echo UTE-MRI sequence, is a sensitive quantitative technique to the age- and bone-loss-related changes of the lower leg tendons. Methods This is a cross-sectional study conducted between January 2018 to February 2020 in the lower legs of 14 female patients with OPe [72±6 years old, body mass index (BMI) =25.8±6.2 kg/m2] and 31 female patients with OPo (73±6 years old, BMI=22.0±3.8 kg/m2), as well as 30 female subjects with normal bone (Normal, 35±18 years old, BMI =23.2±4.3 kg/m2), were imaged on a 3T clinical scanner using a dual-echo 3D Cones UTE sequence. We defined the apparent long T2 signal fraction (aFrac-LongT2) of tendons as the ratio between the signal at the second echo time (TE =2.2 ms) to the UTE signal. The average aFrac-LongT2 and the cross-sectional area were calculated for the anterior tibialis tendons (ATTs) and the posterior tibialis tendons (PTTs). The Kruskal-Wallis rank test was used to compare the differences in aFrac-LongT2 and the cross-sectional area of the tendons between the groups. Results The aFrac-LongT2 of the ATTs and PTTs were significantly higher in the OPo group compared with the Normal group (22.2% and 34.8% in the ATT and PTT, respectively, P<0.01). The cross-sectional area in the ATTs was significantly higher for the OPo group than in the Normal group (Normal/OPo difference was 28.7, P<0.01). Such a difference for PTTs did not reach the significance level. Mean aFrac-LongT2 and cross-sectional area in the OPe group were higher than the Normal group and lower than the OPo group. However, the differences did not show statistical significance, likely due to the higher BMI in the OPe group. Conclusions Dual-echo UTE-MRI is a rapid quantification technique, and aFrac-LongT2 values showed significant differences in tendons between Normal and OPo patients.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA, USA
| | - Dina Moazamian
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Amir Masoud Afsahi
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Sophia Dwek
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Jiyo Athertya
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Bhavsimran Malhi
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Gina Woods
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Christine B. Chung
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Eric Y. Chang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
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Li YX, Liang XL, Liu J, Ma YJ. Assessment of Osteoporosis at the Lumbar Spine Using Ultrashort Echo Time Magnetization Transfer (UTE-MT) MRI. J Magn Reson Imaging 2024; 59:1285-1298. [PMID: 37470693 PMCID: PMC10799192 DOI: 10.1002/jmri.28910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/21/2023] Open
Abstract
BACKGROUND Bone collagen-matrix contributes to the mechanical properties of bone by imparting tensile strength and elasticity, which can be indirectly quantified by ultrashort echo time magnetization transfer ratio (UTE-MTR) to assess osteoporosis. PURPOSE To evaluate osteoporosis at the human lumbar spine using UTE-MTR. STUDY TYPE Prospective. POPULATION One hundred forty-eight-volunteers (age-range, 50-85; females, N = 90), including 81-normal bone density, 35-osteopenic, and 32-osteoporotic subjects. Ten additional healthy volunteers were recruited to study the intrasession reproducibility of the UTE-MT. FIELD STRENGTH/SEQUENCE 3T/UTE-MT, short repetition-time adiabatic inversion recovery prepared UTE (STAIR-UTE), and iterative decomposition of water-and-fat with echo-asymmetry and least-squares estimation (IDEAL-IQ). ASSESSMENT Fracture risk was calculated using Fracture-Risk-Assessment-Tool (FRAX). Region-of-interests (ROIs) were delineated on the trabecular area in the maps of bone-mineral-density, UTE-MTR, collagen-bound water proton-fraction (CBWPF), and bone-marrow fat fraction (BMFF). STATISTICAL TESTS Linear-regression and Bland-Altman analysis were performed to assess the reproducibility of UTE-MTR measurements in the different scans. UTE-MTR and BMFF were correlated with bone-mineral-density using Pearson's regression and with FRAX scores using nonlinear regression. The abilities of UTE-MTR, CBWPF, and BMFF to discriminate between the three patient subgroups were evaluated using receiver-operator-characteristic (ROC) analysis and area-under-the-curve (AUC). Decision-curve-analysis (DCA) and clinical-impact curves were used to evaluate the value of UTE-MTR in clinical diagnosis. The DeLong test was used to compare the ROC curves. P-value <0.05 was considered statistically significant. RESULTS Excellent reproducibility was obtained for the UTE-MT measurements. UTE-MTR strongly correlated with bone-mineral-density (r = 0.76) and FRAX scores (r = -0.77). UTE-MTR exhibited higher AUCs (≥0.723) than BMFF, indicating its superior ability to distinguish between the three patient subgroups. The DCA and clinical-impact curves confirmed the diagnostic value of UTE-MTR. UTE-MTR and CBWPF showed similar performance in correlation with bone-mineral-density and cohort classification. DATA CONCLUSION UTE-MTR strongly correlates with bone-mineral-density and FRAX and shows great potential in distinguishing between normal, osteopenic, and osteoporotic subjects. EVIDENCE LEVEL 1 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Yu-Xuan Li
- Shanxi Medical University, Taiyuan, China
| | - Xiao-Ling Liang
- Department of Radiology, University of California San Diego, 9452 Medical Center Drive, La Jolla, CA 92037, USA
| | - Jin Liu
- Department of Radiology, University of California San Diego, 9452 Medical Center Drive, La Jolla, CA 92037, USA
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, 9452 Medical Center Drive, La Jolla, CA 92037, USA
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Malhi BS, Moazamian D, Shin SH, Athertya JS, Silva L, Jerban S, Jang H, Chang E, Ma Y, Carl M, Du J. Bi-Exponential 3D UTE-T1ρ Relaxation Mapping of Ex Vivo Human Knee Patellar Tendon at 3T. Bioengineering (Basel) 2024; 11:66. [PMID: 38247943 PMCID: PMC10813751 DOI: 10.3390/bioengineering11010066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/30/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
Introduction: The objective of this study was to assess the bi-exponential relaxation times and fractions of the short and long components of the human patellar tendon ex vivo using three-dimensional ultrashort echo time T1ρ (3D UTE-T1ρ) imaging. Materials and Methods: Five cadaveric human knee specimens were scanned using a 3D UTE-T1ρ imaging sequence on a 3T MR scanner. A series of 3D UTE-T1ρ images were acquired and fitted using single-component and bi-component models. Single-component exponential fitting was performed to measure the UTE-T1ρ value of the patellar tendon. Bi-component analysis was performed to measure the short and long UTE-T1ρ values and fractions. Results: The single-component analysis showed a mean single-component UTE-T1ρ value of 8.4 ± 1.7 ms for the five knee patellar tendon samples. Improved fitting was achieved with bi-component analysis, which showed a mean short UTE-T1ρ value of 5.5 ± 0.8 ms with a fraction of 77.6 ± 4.8%, and a mean long UTE-T1ρ value of 27.4 ± 3.8 ms with a fraction of 22.4 ± 4.8%. Conclusion: The 3D UTE-T1ρ sequence can detect the single- and bi-exponential decay in the patellar tendon. Bi-component fitting was superior to single-component fitting.
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Affiliation(s)
- Bhavsimran Singh Malhi
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Dina Moazamian
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Soo Hyun Shin
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Jiyo S. Athertya
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Livia Silva
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Saeed Jerban
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Hyungseok Jang
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Eric Chang
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
| | - Yajun Ma
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
| | - Michael Carl
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
- General Electric Health Care, San Diego, CA 92037, USA
| | - Jiang Du
- Department of Radiology, University of California, La Jolla, San Diego, CA 92037, USA; (B.S.M.); (D.M.); (S.H.S.); (J.S.A.); (L.S.); (S.J.); (H.J.); (E.C.); (Y.M.); (M.C.)
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
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Zhang X, Zhou B, Chen Y, Cai Z, Guo Y, Wei Z, Li S, Feng Y, Sedaghat S, Jang H. Evaluation of gadolinium deposition in cortical bone using three-dimensional ultrashort echo time quantitative susceptibility mapping: A preliminary study. NMR Biomed 2024; 37:e5035. [PMID: 37721094 PMCID: PMC10726698 DOI: 10.1002/nbm.5035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 08/15/2023] [Accepted: 08/17/2023] [Indexed: 09/19/2023]
Abstract
The aim of the current study was to investigate the feasibility of three-dimensional ultrashort echo time quantitative susceptibility mapping (3D UTE-QSM) for the assessment of gadolinium (Gd) deposition in cortical bone. To this end, 40 tibial bovine cortical bone specimens were divided into five groups then soaked in phosphate-buffered saline (PBS) solutions with five different Gd concentrations of 0, 0.4, 0.8, 1.2, and 1.6 mmol/L for 48 h. Additionally, eight rabbits were randomly allocated into three groups, consisting of a normal-dose macrocyclic gadolinium-based contrast agent (GBCA) group (n = 3), a high-dose macrocyclic GBCA group (n = 3), and a control group (n = 2). All bovine and rabbit tibial bone samples underwent magnetic resonance imaging (MRI) on a 3-T clinical MR system. A 3D UTE-Cones sequence was utilized to acquire images with five different echo times (i.e., 0.032, 0.2, 0.4, 0.8, and 1.2 ms). The UTE images were subsequently processed with the morphology-enabled dipole inversion algorithm to yield a susceptibility map. The average susceptibility was calculated in three regions of interest in the middle of each specimen, and the Pearson's correlation between the estimated susceptibility and Gd concentration was calculated. The bone samples soaked in PBS with higher Gd concentrations exhibited elevated susceptibility values. A mean susceptibility value of -2.47 ± 0.23 ppm was observed for bovine bone soaked in regular PBS, while the mean QSM value increased to -1.75 ± 0.24 ppm for bone soaked in PBS with the highest Gd concentration of 1.6 mmol/L. A strong positive correlation was observed between Gd concentrations and QSM values. The mean susceptibility values of rabbit tibial specimens in the control group, normal-dose GBCA group, and high-dose GBCA group were -4.11 ± 1.52, -3.85 ± 1.33, and -3.39 ± 1.35 ppm, respectively. In conclusion, a significant linear correlation between Gd in cortical bone and QSM values was observed. The preliminary results suggest that 3D UTE-QSM may provide sensitive noninvasive assessment of Gd deposition in cortical bone.
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Affiliation(s)
- Xiaodong Zhang
- Department of Radiology, Third Affiliated Hospital of Southern Medical University, Guangzhou, China
- University of California, San Diego, San Diego, CA, United States
| | - Beibei Zhou
- The Third School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Yanjun Chen
- Department of Radiology, Third Affiliated Hospital of Southern Medical University, Guangzhou, China
- University of California, San Diego, San Diego, CA, United States
| | - Zhenyu Cai
- University of California, San Diego, San Diego, CA, United States
| | - Yihao Guo
- School of Biomedical Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, China
| | - Zhao Wei
- University of California, San Diego, San Diego, CA, United States
| | - Shisi Li
- Department of Radiology, Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Yanqiu Feng
- School of Biomedical Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, China
| | - Sam Sedaghat
- University of California, San Diego, San Diego, CA, United States
| | - Hyungseok Jang
- University of California, San Diego, San Diego, CA, United States
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Zhou Z, Li Q, Liao C, Cao X, Liang H, Chen Q, Pu R, Ye H, Tong Q, He H, Zhong J. Optimized three-dimensional ultrashort echo time: Magnetic resonance fingerprinting for myelin tissue fraction mapping. Hum Brain Mapp 2023; 44:2209-2223. [PMID: 36629336 PMCID: PMC10028641 DOI: 10.1002/hbm.26203] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 12/12/2022] [Accepted: 01/01/2023] [Indexed: 01/12/2023] Open
Abstract
Quantitative assessment of brain myelination has gained attention for both research and diagnosis of neurological diseases. However, conventional pulse sequences cannot directly acquire the myelin-proton signals due to its extremely short T2 and T2* values. To obtain the myelin-proton signals, dedicated short T2 acquisition techniques, such as ultrashort echo time (UTE) imaging, have been introduced. However, it remains challenging to isolate the myelin-proton signals from tissues with longer T2. In this article, we extended our previous two-dimensional ultrashort echo time magnetic resonance fingerprinting (UTE-MRF) with dual-echo acquisition to three dimensional (3D). Given a relatively low proton density (PD) of myelin-proton, we utilized Cramér-Rao Lower Bound to encode myelin-proton with the maximal SNR efficiency for optimizing the MR fingerprinting design, in order to improve the sensitivity of the sequence to myelin-proton. In addition, with a second echo of approximately 3 ms, myelin-water component can be also captured. A myelin-tissue (myelin-proton and myelin-water) fraction mapping can be thus calculated. The optimized 3D UTE-MRF with dual-echo acquisition is tested in simulations, physical phantom and in vivo studies of both healthy subjects and multiple sclerosis patients. The results suggest that the rapidly decayed myelin-proton and myelin-water signal can be depicted with UTE signals of our method at clinically relevant resolution (1.8 mm isotropic) in 15 min. With its good sensitivity to myelin loss in multiple sclerosis patients demonstrated, our method for the whole brain myelin-tissue fraction mapping in clinical friendly scan time has the potential for routine clinical imaging.
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Affiliation(s)
- Zihan Zhou
- Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou, Zhejiang, China
| | - Qing Li
- Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China
- MR Collaborations, Siemens Healthineers Ltd, Shanghai, China
| | - Congyu Liao
- Department of Radiology, Stanford University, Stanford, California, USA
- Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - Xiaozhi Cao
- Department of Radiology, Stanford University, Stanford, California, USA
- Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - Hui Liang
- Department of Neurology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Quan Chen
- Department of Radiology, Stanford University, Stanford, California, USA
- Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - Run Pu
- Neusoft Medical Systems, Shanghai, China
| | - Huihui Ye
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Qiqi Tong
- Research Center for Healthcare Data Science, Zhejiang Lab, Hangzhou, Zhejiang, China
| | - Hongjian He
- Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou, Zhejiang, China
- School of Physics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jianhui Zhong
- Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China
- Department of Imaging Sciences, University of Rochester, Rochester, New York, USA
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Lombardi AF, Ma Y, Jang H, Jerban S, Tang Q, Searleman AC, Meyer RS, Du J, Chang EY. AcidoCEST-UTE MRI Reveals an Acidic Microenvironment in Knee Osteoarthritis. Int J Mol Sci 2022; 23:4466. [PMID: 35457284 PMCID: PMC9027981 DOI: 10.3390/ijms23084466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/08/2022] [Accepted: 04/13/2022] [Indexed: 02/01/2023] Open
Abstract
A relationship between an acidic pH in the joints, osteoarthritis (OA), and pain has been previously demonstrated. Acidosis Chemical Exchange Saturation Transfer (acidoCEST) indirectly measures the extracellular pH through the assessment of the exchange of protons between amide groups on iodinated contrast agents and bulk water. It is possible to estimate the extracellular pH in the osteoarthritic joint using acidoCEST MRI. However, conventional MR sequences cannot image deep layers of cartilage, meniscus, ligaments, and other musculoskeletal tissues that present with short echo time and fast signal decay. Ultrashort echo time (UTE) MRI, on the other hand, has been used successfully to image those joint tissues. Here, our goal is to compare the pH measured in the knee joints of volunteers without OA and patients with severe OA using acidoCEST-UTE MRI. Patients without knee OA and patients with severe OA were examined using acidoCEST-UTE MRI and the mean pH of cartilage, meniscus, and fluid was calculated. Additionally, the relationship between the pH measurements and the Knee Injury and Osteoarthritis Outcome Score (KOOS) was investigated. AcidoCEST-UTE MRI can detect significant differences in the pH of knee cartilage, meniscus, and fluid between joints without and with OA, with OA showing lower pH values. In addition, symptoms and knee-joint function become worse at lower pH measurements.
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Affiliation(s)
- Alecio F. Lombardi
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (E.Y.C.)
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Yajun Ma
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Hyungseok Jang
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Saeed Jerban
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Qingbo Tang
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (E.Y.C.)
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Adam C. Searleman
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Robert Scott Meyer
- Orthopaedic Surgery Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA;
| | - Jiang Du
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
| | - Eric Y. Chang
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (E.Y.C.)
- Department of Radiology, University of California San Diego, San Diego, CA 92161, USA; (Y.M.); (H.J.); (S.J.); (A.C.S.); (J.D.)
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Afsahi AM, Sedaghat S, Moazamian D, Afsahi G, Athertya JS, Jang H, Ma YJ. Articular Cartilage Assessment Using Ultrashort Echo Time MRI: A Review. Front Endocrinol (Lausanne) 2022; 13:892961. [PMID: 35692400 PMCID: PMC9178905 DOI: 10.3389/fendo.2022.892961] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/14/2022] [Indexed: 01/05/2023] Open
Abstract
Articular cartilage is a major component of the human knee joint which may be affected by a variety of degenerative mechanisms associated with joint pathologies and/or the aging process. Ultrashort echo time (UTE) sequences with a TE less than 100 µs are capable of detecting signals from both fast- and slow-relaxing water protons in cartilage. This allows comprehensive evaluation of all the cartilage layers, especially for the short T2 layers which include the deep and calcified zones. Several ultrashort echo time (UTE) techniques have recently been developed for both morphological imaging and quantitative cartilage assessment. This review article summarizes the current catalog techniques based on UTE Magnetic Resonance Imaging (MRI) that have been utilized for such purposes in the human knee joint, such as T1, T2∗ , T1ρ, magnetization transfer (MT), double echo steady state (DESS), quantitative susceptibility mapping (QSM) and inversion recovery (IR). The contrast mechanisms as well as the advantages and disadvantages of these techniques are discussed.
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Affiliation(s)
- Amir Masoud Afsahi
- Department of Radiology, University of California San Diego, San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, United States
| | - Sam Sedaghat
- Department of Radiology, University of California San Diego, San Diego, CA, United States
| | - Dina Moazamian
- Department of Radiology, University of California San Diego, San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, United States
| | - Ghazaleh Afsahi
- Department of Biotechnology Research, BioSapien, San Diego, CA, United States
| | - Jiyo S. Athertya
- Department of Radiology, University of California San Diego, San Diego, CA, United States
| | - Hyungseok Jang
- Department of Radiology, University of California San Diego, San Diego, CA, United States
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, San Diego, CA, United States
- *Correspondence: Ya-Jun Ma,
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Zhang M, Li Z, Wang H, Chen T, Lu Y, Yan F, Zhang Y, Wei H. Simultaneous Quantitative Susceptibility Mapping of Articular Cartilage and Cortical Bone of Human Knee Joint Using Ultrashort Echo Time Sequences. Front Endocrinol (Lausanne) 2022; 13:844351. [PMID: 35273576 PMCID: PMC8901574 DOI: 10.3389/fendo.2022.844351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 01/31/2022] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND It is of great clinical importance to assess the microstructure of the articular cartilage and cortical bone of the human knee joint. While quantitative susceptibility mapping (QSM) is a promising tool for investigating the knee joint, however, previous QSM studies using conventional gradient recalled echo sequences or ultrashort echo time (UTE) sequences only focused on mapping the magnetic susceptibility of the articular cartilage or cortical bone, respectively. Simultaneously mapping the underlying susceptibilities of the articular cartilage and cortical bone of human in vivo has not been explored and reported. METHOD Three-dimensional multi-echo radial UTE sequences with the shortest TE of 0.07 msec and computed tomography (CT) were performed on the bilateral knee joints of five healthy volunteers for this prospective study. UTE-QSM was reconstructed from the local field map after water-fat separation and background field removal. Spearman's correlation analysis was used to explore the relationship between the magnetic susceptibility and CT values in 158 representative regions of interest of cortical bone. RESULT The susceptibility properties of the articular cartilage and cortical bone were successfully quantified by UTE-QSM. The laminar structure of articular cartilage was characterized by the difference of susceptibility value in each layer. Susceptibility was mostly diamagnetic in cortical bone. A significant negative correlation (r=-0.43, p<0.001) between the susceptibility value and CT value in cortical bone was observed. CONCLUSION UTE-QSM enables simultaneous susceptibility mapping of the articular cartilage and cortical bone of human in vivo. Good association between susceptibility and CT values in cortical bone suggests the potential of UTE-QSM for bone mapping for further clinical application.
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Affiliation(s)
- Ming Zhang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Zhihui Li
- Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Hanqi Wang
- Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Tongtong Chen
- Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yong Lu
- Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Fuhua Yan
- Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yuyao Zhang
- School of Information and Science and Technology, ShanghaiTech University, Shanghai, China
| | - Hongjiang Wei
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
- *Correspondence: Hongjiang Wei,
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Liu J, Liao JW, Li W, Chen XJ, Feng JX, Yao L, Huang PH, Su ZH, Lu H, Liao YT, Li SL, Ma YJ. Assessment of Osteoporosis in Lumbar Spine: In Vivo Quantitative MR Imaging of Collagen Bound Water in Trabecular Bone. Front Endocrinol (Lausanne) 2022; 13:801930. [PMID: 35250862 PMCID: PMC8888676 DOI: 10.3389/fendo.2022.801930] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/21/2022] [Indexed: 11/17/2022] Open
Abstract
AIM Bone collagen matrix makes a crucial contribution to the mechanical properties of bone by imparting tensile strength and elasticity. The collagen content of bone is accessible via quantification of collagen bound water (CBW) indirectly. We prospectively study the performance of the CBW proton density (CBWPD) measured by a 3D short repetition time adiabatic inversion recovery prepared ultrashort echo time (STAIR-UTE) magnetic resonance imaging (MRI) sequence in the diagnosis of osteoporosis in human lumbar spine. METHODS A total of 189 participants with a mean age of 56 (ranged from 50 to 86) years old were underwent MRI, quantitative computed tomography (QCT), and dual-energy X-ray absorptiometry (DXA) in lumbar spine. Major fracture risk was also evaluated for all participants using Fracture Risk Assessment Tool (FRAX). Lumbar CBWPD, bone marrow fat fraction (BMFF), bone mineral density (BMD) and T score values were calculated in three vertebrae (L2-L4) for each subject. Both the CBWPD and BMFF were correlated with BMD, T score, and FRAX score for comparison. The abilities of the CBWPD and BMFF to discriminate between three different cohorts, which included normal subjects, patients with osteopenia, and patients with osteoporosis, were also evaluated and compared using receiver operator characteristic (ROC) analysis. RESULTS The CBWPD showed strong correlation with standard BMD (R2 = 0.75, P < 0.001) and T score (R2 = 0.59, P < 0.001), as well as a moderate correlation with FRAX score (R2 = 0.48, P < 0.001). High area under the curve (AUC) values (≥ 0.84 using QCT as reference; ≥ 0.76 using DXA as reference) obtained from ROC analysis demonstrated that the CBWPD was capable of well differentiating between the three different subject cohorts. Moreover, the CBWPD had better correlations with BMD, T score, and FRAX score than BMFF, and also performed better in cohort discrimination. CONCLUSION The STAIR-UTE-measured CBWPD is a promising biomarker in the assessment of bone quality and fracture risk.
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Affiliation(s)
- Jin Liu
- Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | - Jian-Wei Liao
- Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | - Wei Li
- Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | - Xiao-Jun Chen
- Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | - Jia-Xin Feng
- Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | - Lin Yao
- Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | - Pan-Hui Huang
- Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | - Zhi-Hai Su
- Department of Spinal Surgery, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | - Hai Lu
- Department of Spinal Surgery, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
| | | | - Shao-Lin Li
- Department of Radiology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, China
- *Correspondence: Shao-Lin Li,
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, La Jolla, CA, United States
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Cha MJ, Ahn HS, Choi H, Park HJ, Benkert T, Pfeuffer J, Paek MY. Accelerated Stack-of-Spirals Free-Breathing Three-Dimensional Ultrashort Echo Time Lung Magnetic Resonance Imaging: A Feasibility Study in Patients With Breast Cancer. Front Oncol 2021; 11:746059. [PMID: 34692529 PMCID: PMC8529215 DOI: 10.3389/fonc.2021.746059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 09/20/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose To investigate the clinical feasibility of accelerated free-breathing stack-of-spirals (spiral) three-dimensional (3D) ultrashort echo time (UTE) lung magnetic resonance imaging (MRI) using iterative self‐consistent parallel imaging reconstruction from arbitrary k‐space (SPIRiT) algorithm in patients with breast cancer. Methods The institutional review board approved this prospective study and patients’ informed consents were obtained. Between June and August 2018, 29 female patients with breast cancer underwent 3-T MRI including accelerated free-breathing spiral 3D UTE (0.98-mm isotropic spatial resolution; echo time, 0.05 msec) of the lungs and thin-section chest computed tomography (CT). Two radiologists evaluated the image quality and pulmonary nodules on MRI were assessed and compared, CT as a reference. Results The pulmonary vessels and bronchi were visible consistently up to the sub-sub-segmental and sub-segmental branch levels, respectively, on accelerated spiral 3D UTE. The overall image quality was evaluated as good and excellent for 70.7% of accelerated spiral 3D UTE images (reviewer [R]1, 72.4% [21/29]; R2, 69.0% [20/29]) and acceptable for 20.7% (both R1 and R2, 20.7% [6/29]). Five patients on CT revealed 141 pulmonary metastatic nodules (5.3 ± 2.6 mm); the overall nodule detection rate of accelerated spiral 3D UTE was sensitivity of 90.8% (128/141), accuracy of 87.7%, and positive predictive value of 96.2%. In the Bland-Altman plot analysis comparing nodule size between CT and MRI, 132/141 nodules (93.6%) were inside the limits of agreement. Conclusion Accelerated free-breathing spiral 3D UTE using the SPIRiT algorithm could be a potential alternative to CT for oncology patients.
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Affiliation(s)
- Min Jae Cha
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, South Korea
| | - Hye Shin Ahn
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, South Korea
| | - Hyewon Choi
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, South Korea
| | - Hyun Jeong Park
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, South Korea
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13
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Xiong X, Ye Z, Tang H, Wei Y, Nie L, Wei X, Liu Y, Song B. MRI of Temporomandibular Joint Disorders: Recent Advances and Future Directions. J Magn Reson Imaging 2021; 54:1039-1052. [PMID: 32869470 DOI: 10.1002/jmri.27338] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 08/07/2020] [Accepted: 08/07/2020] [Indexed: 02/05/2023] Open
Abstract
Temporomandibular joint disorders (TMDs) are a prevalent disease covering pain and dysfunction of temporomandibular joints and masticatory muscles, which can be detrimental to quality of life. Magnetic resonance imaging (MRI) is a powerful and noninvasive tool for the imaging and understanding of TMD. With the recent technical development of dynamic and quantitative MRI techniques, including diffusion-weighted imaging, T2 mapping, and ultrashort/zero echo time, it is now feasible in TMD imaging and has been preliminarily investigated with promising results. In this review we will discuss the recent advances of MRI techniques in TMD and its future directions, and hope to highlight the scientific potential and clinical value of novel MRI techniques in diagnosing and treating TMD. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 3.
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Affiliation(s)
- Xin Xiong
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Zheng Ye
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Hehan Tang
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Yi Wei
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | | | | | - Yang Liu
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Bin Song
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
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Lombardi AF, Wei Z, Wong J, Carl M, Lee RR, Wallace M, Masuda K, Chang EY, Du J, Ma YJ. High contrast cartilaginous endplate imaging using a 3D adiabatic inversion-recovery-prepared fat-saturated ultrashort echo time (3D IR-FS-UTE) sequence. NMR Biomed 2021; 34:e4579. [PMID: 34219287 PMCID: PMC8944187 DOI: 10.1002/nbm.4579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 06/10/2021] [Accepted: 06/12/2021] [Indexed: 05/08/2023]
Abstract
Ultrashort echo time (UTE) sequences can image tissues with transverse T 2 /T 2 * relaxations too short to be efficiently observed on routine clinical MRI sequences, such as the vertebral body cartilaginous endplate (CEP). Here, we describe a 3D adiabatic inversion-recovery-prepared fat-saturated ultrashort echo time (3D IR-FS-UTE) sequence to highlight the CEP of vertebral bodies in comparison to the intervertebral disc (IVD) and bone marrow fat (BF) at 3 T. The IR-FS-UTE sequence used a 3D UTE sequence combined with an adiabatic IR preparation pulse centered in the middle of the water and fat peaks, while a fat saturation module was used to suppress the signal from fat. A slab-selective half pulse was used for signal excitation, and a 3D center-out cones trajectory was used for more efficient data sampling. The 3D IR-FS-UTE sequence was applied to an ex vivo human spine sample, as well as the spines of six healthy volunteers and of three patients with back pain. Bright continuous lines representing signal from CEP were found in healthy IVDs. The measured contrast-to-noise ratio was 18.5 ± 4.9 between the CEP and BF, and 20.3 ± 4.15 between the CEP and IVD for the six volunteers. Abnormal IVDs showed CEP discontinuity or irregularity in the sample and patient studies. In conclusion, the proposed 3D IR-FS-UTE sequence is feasible for imaging the vertebral body's CEP in vivo with high contrast.
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Affiliation(s)
- Alecio F. Lombardi
- Department of Radiology, University of California San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, CA, United States
| | - Zhao Wei
- Department of Radiology, University of California San Diego, CA, United States
| | - Jonathan Wong
- Department of Radiology, University of California San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, CA, United States
| | | | - Roland R. Lee
- Department of Radiology, University of California San Diego, CA, United States
| | - Mark Wallace
- Department of Anesthesiology, University of California San Diego, CA, United States
| | - Koichi Masuda
- Department of Orthopedic Surgery, University of California San Diego, CA, United States
| | - Eric Y. Chang
- Department of Radiology, University of California San Diego, CA, United States
- Research Service, Veterans Affairs San Diego Healthcare System, CA, United States
| | - Jiang Du
- Department of Radiology, University of California San Diego, CA, United States
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, CA, United States
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Heo YJ, Jeong HW, Kim D, Baek JW, Han JY, Choo HJ, Kim ST, Jeong YG, Jin SC. Usefulness of pointwise encoding time reduction with radial acquisition sequence in subtraction-based magnetic resonance angiography for follow-up of the Neuroform Atlas stent-assisted coil embolization for cerebral aneurysms. Acta Radiol 2021; 62:1193-1199. [PMID: 32867507 DOI: 10.1177/0284185120952784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Although time-of-flight magnetic resonance angiography (TOF-MRA) is widely used, it has limited usefulness for follow-up after stent-assisted coil embolization. Contrast-enhanced MRA (CE-MRA) and ultrashort echo time MRA have been suggested as alternative methods for visualization after this procedure. PURPOSE To compare efficacy and usefulness of pointwise encoding time reduction with radial acquisition (PETRA) sequence in subtraction-based MRA (qMRA), TOF-MRA, and CE-MRA during the follow-up after Neuroform Atlas stent-assisted coil embolization for intracranial aneurysms. MATERIAL AND METHODS This retrospective study included 23 patients with 24 aneurysms who underwent Neuroform Atlas stent-assisted coil embolization for intracranial aneurysms. All patients were evaluated with PETRA qMRA, TOF-MRA, and CE-MRA at the same follow-up session. The flow within stents, occlusion status, and presence of pseudo-stenosis were evaluated; inter-observer and intermodality agreements for the three methods were also graded. RESULTS The mean score for flow visualization within the stents was significantly higher for PETRA qMRA and CE-MRA than for TOF-MRA (although no significant difference was found between PETRA qMRA and CE-MRA). Good inter-observer agreement was observed for each modality. PETRA qMRA and CE-MRA were more consistent with digital subtraction angiography (DSA) than TOF-MRA for aneurysm occlusion status. The intermodality agreement was better between PETRA qMRA and DSA, and between CE-MRA and DSA, than between DSA and TOF-MRA. Pseudo-stenosis was most frequently observed in TOF-MRA, followed by CE-MRA and PETRA qMRA. CONCLUSION PETRA qMRA is useful for evaluating the parent artery patency and occlusion status of aneurysms after Neuroform Atlas stent-assisted coil embolization.
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Affiliation(s)
- Young Jin Heo
- Department of Radiology, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Hae Woong Jeong
- Department of Radiology, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Donghyun Kim
- Department of Radiology, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Jin Wook Baek
- Department of Radiology, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Ji-yeon Han
- Department of Radiology, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Hye Jung Choo
- Department of Radiology, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Sung Tae Kim
- Department of Neurosurgery, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Young Gyun Jeong
- Department of Neurosurgery, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Sung-Chul Jin
- Department of Neurosurgery, Inje University Haeundae Paik Hospital, Busan, Republic of Korea
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Lombardi AF, Jang H, Wei Z, Jerban S, Wallace M, Masuda K, Ma YJ. High-contrast osteochondral junction imaging using a 3D dual adiabatic inversion recovery-prepared ultrashort echo time cones sequence. NMR Biomed 2021; 34:e4559. [PMID: 34021649 PMCID: PMC8254801 DOI: 10.1002/nbm.4559] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/14/2021] [Accepted: 05/06/2021] [Indexed: 05/08/2023]
Abstract
While conventional MRI sequences cannot visualize tissues from the osteochondral junction (OCJ) due to these tissues' short transverse T2 /T2 * relaxations, ultrashort echo time (UTE) sequences can overcome this limitation. A 2D UTE sequence with a dual adiabatic inversion recovery preparation (DIR-UTE) for selective imaging of short T2 tissues with high contrast has previously been developed, but high sensitivity to eddy currents and aliased out-of-slice excitation make it difficult to image the thin layer of the OCJ in vivo. Here, we combine the DIR scheme with a 3D UTE cones sequence for volumetric imaging of OCJ tissues in vivo, aiming to generate higher OCJ contrast compared with a recently developed single IR-prepared UTE sequence with a fat saturation module (IR-FS-UTE). All sequences were implemented on a 3-T clinical scanner. The DIR-UTE cones sequence combined a 3D UTE cones sequence with two narrow-band adiabatic IR preparation pulses centered on water and fat spectrum frequencies, respectively. The 3D DIR-UTE cones sequence was first applied to a phantom, then to the knees of four healthy volunteers and four patients diagnosed with osteoarthritis and compared with the IR-FS-UTE sequence. In both phantom and volunteer studies, the proposed DIR-UTE cones sequence showed much higher contrast for OCJ imaging than the IR-FS-UTE sequence did. The 3D DIR-UTE cones sequence showed a significantly higher contrast-to-noise ratio between the OCJ and subchondral bone fat (mean, standard deviation [SD]: 25.7 ± 2.3) and between the OCJ and superficial layers of cartilage (mean, SD: 22.2 ± 3.5) compared with the IR-FS-UTE sequence (mean, SD: 10.8 ± 2.5 and 16.3 ± 2.6, respectively). The 3D DIR-UTE cones sequence is feasible for imaging of the OCJ region of the knee in vivo and produces both high resolution and high contrast.
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Affiliation(s)
- Alecio F. Lombardi
- Department of Radiology, University of California, San Diego, CA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA
| | - Zhao Wei
- Department of Radiology, University of California, San Diego, CA
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, CA
| | - Mark Wallace
- Department of Anesthesiology, University of California San Diego, La Jolla, CA
| | - Koichi Masuda
- Department of Orthopedic Surgery, University of California San Diego, La Jolla, CA
| | - Ya-Jun Ma
- Department of Radiology, University of California, San Diego, CA
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17
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Xue YP, Ma YJ, Wu M, Jerban S, Wei Z, Chang EY, Du J. Quantitative 3D Ultrashort Echo Time Magnetization Transfer Imaging for Evaluation of Knee Cartilage Degeneration In Vivo. J Magn Reson Imaging 2021; 54:1294-1302. [PMID: 33894091 DOI: 10.1002/jmri.27659] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 04/08/2021] [Accepted: 04/08/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Recent studies suggest that macromolecular fraction (MMF) derived from three-dimensional ultrashort echo time magnetization transfer (UTE-MT) imaging is insensitive to the magic angle effect. However, its clinical use in osteoarthritis (OA) remains to be investigated. PURPOSE To investigate the feasibility of 3D UTE-MT-derived MMF in differentiating normal from degenerated cartilage. STUDY TYPE Prospective. SUBJECTS Sixty-two participants (54.8 ± 16.7 years, 30 females) with and without OA, plus two healthy volunteers (mean age 35.0 years) for reproducibility test. FIELD STRENGTH/SEQUENCE 3 T/UTE-MT sequence. ASSESSMENT A 3D UTE-MT sequence was employed to calculate MMF based on a two-pool model. Kellgren-Lawrence (KL) grade and Whole-Organ Magnetic Resonance Imaging Score (WORMS) were evaluated by three experienced musculoskeletal radiologists. KL grade was condensed into three groups: KL0, KL1-2, and KL3-4. WORMS was regrouped based on extent of lesion (extent group) and depth of lesion (depth group), respectively. The performance of MMF at evaluating the degeneration of cartilage was assessed via Spearman's correlation coefficient and the area under the curve (AUC) calculated according to the receiver-operating characteristic curve. STATISTICAL TESTS After normality check, one-way analysis of variance was used to evaluate the performance. Tukey-Kramer test was performed for post hoc testing. RESULTS MMF showed significant negative correlations with KL grade (r = -0.53, P < 0.05) and WORMS (r = -0.49, P < 0.05). Significantly lower MMFs were found in subjects with greater KL grade (11.8 ± 0.8% for KL0; 10.9 ± 0.9% for KL1-2; 10.6 ± 1.1% for KL3-4; P < 0.05) and in cartilage with greater extent (12.1 ± 1.6% for normal cartilage; 10.9 ± 1.6% for regional lesions; 9.6 ± 1.7% for diffuse lesions; P < 0.05) and depth (12.1 ± 1.6% for normal cartilage; 10.6 ± 1.6% for partial-thickness lesions; 8.8 ± 1.7% for full-thickness lesions; P < 0.05) of lesions. AUC values of MMF for doubtful-minimal OA (KL1-2) and mild cartilage degradation (WORMS1-2) were 0.8 and 0.7, respectively. DATA CONCLUSION This study highlights the clinical potential of MMF in the detection of early OA. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY STAGE: 2.
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Affiliation(s)
- Yan-Ping Xue
- Department of Radiology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China.,Department of Radiology, University of California San Diego, La Jolla, California, USA
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, La Jolla, California, USA
| | - Mei Wu
- Department of Radiology, University of California San Diego, La Jolla, California, USA
| | - Saeed Jerban
- Department of Radiology, University of California San Diego, La Jolla, California, USA
| | - Zhao Wei
- Department of Radiology, University of California San Diego, La Jolla, California, USA
| | - Eric Y Chang
- Department of Radiology, University of California San Diego, La Jolla, California, USA.,Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, California, USA
| | - Jiang Du
- Department of Radiology, University of California San Diego, La Jolla, California, USA
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18
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Anjum MAR, Gonzalez FM, Swain A, Leisen J, Hosseini Z, Singer A, Umpierrez M, Reiter DA. Multi-component T 2 ∗ relaxation modelling in human Achilles tendon: Quantifying chemical shift information in ultra-short echo time imaging. Magn Reson Med 2021; 86:415-428. [PMID: 33590557 DOI: 10.1002/mrm.28686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 12/21/2020] [Accepted: 12/23/2020] [Indexed: 11/10/2022]
Abstract
PURPOSE To examine multi-component relaxation modelling for quantification of on- and off-resonance relaxation signals in multi-echo ultra-short echo time (UTE) data of human Achilles tendon (AT) and compare bias and dispersion errors of model parameters to that of the bi-component model. THEORY AND METHODS Multi-component modelling is demonstrated for quantitative multi-echo UTE analysis of AT and supported using a novel method for determining number of MR-visible off-resonance components, UTE data from six healthy volunteers, and analysis of proton NMR measurements from ex vivo bovine AT. Cramer-Rao lower bound expressions are presented for multi- and bi-component models and parameter estimate variances are compared. Bias error in bi-component estimates is characterized numerically. RESULTS Two off-resonance components were consistently detected in all six volunteers and in bovine AT data. Multi-component model exhibited superior quality of fit, with a marginal increase in estimate variance, when compared to the bi-component model. Bi-component estimates exhibited notable bias particularly in R 2 , 1 ∗ in the presence of off-resonance components. CONCLUSION Multi-component modelling more reliably quantifies tendon matrix water components while also providing quantitation of additional non-water matrix constituents. Further work is needed to interpret the origin of the observed off-resonance signals with preliminary assignments made to chemical groups in lipids and proteoglycans.
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Affiliation(s)
- Muhammad A R Anjum
- Department of Radiology & Imaging Sciences, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Felix M Gonzalez
- Department of Radiology & Imaging Sciences, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Anshuman Swain
- Department of Radiology & Imaging Sciences, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Johannes Leisen
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Zahra Hosseini
- MR R&D Collaborations, Siemens Medical Solutions Inc., Atlanta, Georgia, USA
| | - Adam Singer
- Department of Radiology & Imaging Sciences, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Monica Umpierrez
- Department of Radiology & Imaging Sciences, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - David A Reiter
- Department of Radiology & Imaging Sciences, School of Medicine, Emory University, Atlanta, Georgia, USA.,Department of Orthopedics, School of Medicine, Emory University, Atlanta, Georgia, USA
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19
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Gouwens KR, Higano NS, Marks KT, Stimpfl JN, Hysinger EB, Woods JC, Kingma PS. Magentic Resonance Imaging Evaluation of Regional Lung Vts in Severe Neonatal Bronchopulmonary Dysplasia. Am J Respir Crit Care Med 2020; 202:1024-1031. [PMID: 32459506 DOI: 10.1164/rccm.202001-0213oc] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Rationale: Bronchopulmonary dysplasia is a heterogeneous lung disease characterized by regions of cysts and fibrosis, but methods for evaluating lung function are limited to whole lung rather than specific regions of interest.Objectives: Respiratory-gated, ultrashort echo time magnetic resonance imaging was used to test the hypothesis that cystic regions of the lung will exhibit a quantifiable Vt that will correlate with ventilator settings and clinical outcomes.Methods: Magnetic resonance images of 17 nonsedated, quiet-breathing infants with severe bronchopulmonary dysplasia were reconstructed into end-inspiration and end-expiration images. Cysts were identified and measured by using density threshold combined with manual identification and segmentation. Regional Vts were calculated by subtracting end-expiration from end-inspiration volumes in total lung, noncystic lung, total-cystic lung, and individual large cysts.Measurements and Main Results: Cystic lung areas averaged larger Vts than noncystic lung when normalized by volume (0.8 ml Vt/ml lung vs. 0.1 ml Vt/ml lung, P < 0.002). Cyst Vt correlates with cyst size (P = 0.012 for total lung cyst and P < 0.002 for large cysts), although there was variability between individual cyst Vt, with 22% of cysts demonstrating negative Vt. Peak inspiratory pressure positively correlated with total lung Vt (P = 0.027) and noncystic Vt (P = 0.015) but not total lung cyst Vt (P = 0.8). Inspiratory time and respiratory rate did not improve Vt of any analyzed lung region.Conclusions: Cystic lung has greater normalized Vt when compared with noncystic lung. Ventilator pressure increases noncystic lung Vt, but inspiratory time does not correlate with Vt of normal or cystic lung.
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Affiliation(s)
- Kara R Gouwens
- The Perinatal Institute.,Cincinnati Bronchopulmonary Dysplasia Center
| | - Nara S Higano
- Cincinnati Bronchopulmonary Dysplasia Center.,Center for Pulmonary Imaging Research.,Department of Radiology, and.,Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; and
| | | | | | - Erik B Hysinger
- Cincinnati Bronchopulmonary Dysplasia Center.,Center for Pulmonary Imaging Research.,Department of Radiology, and.,Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; and.,Department of Pediatrics and
| | - Jason C Woods
- Cincinnati Bronchopulmonary Dysplasia Center.,Center for Pulmonary Imaging Research.,Department of Radiology, and.,Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; and.,Department of Pediatrics and.,Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Paul S Kingma
- The Perinatal Institute.,Cincinnati Bronchopulmonary Dysplasia Center.,Center for Pulmonary Imaging Research.,Department of Radiology, and.,Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; and.,Department of Pediatrics and
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20
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Wu M, Ma Y, Wan L, Jerban S, Jang H, Chang EY, Du J. Magic angle effect on adiabatic T 1ρ imaging of the Achilles tendon using 3D ultrashort echo time cones trajectory. NMR Biomed 2020; 33:e4322. [PMID: 32431025 PMCID: PMC7393640 DOI: 10.1002/nbm.4322] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/31/2020] [Accepted: 04/14/2020] [Indexed: 05/16/2023]
Abstract
The protons in collagen-rich musculoskeletal (MSK) tissues such as the Achilles tendon are subject to strong dipolar interactions which are modulated by the term (3cos2 θ-1) where θ is the angle between the fiber orientation and the static magnetic field B0 . The purpose of this study was to investigate the magic angle effect in three-dimensional ultrashort echo time Cones Adiabatic T1ρ (3D UTE Cones-AdiabT1ρ ) imaging of the Achilles tendon using a clinical 3 T scanner. The magic angle effect was investigated by Cones-AdiabT1ρ imaging of five cadaveric human Achilles tendon samples at five angular orientations ranging from 0° to 90° relative to the B0 field. Conventional Cones continuous wave T1ρ (Cones-CW-T1ρ ) and Cones T2 * (Cones-T2 *) sequences were also applied for comparison. On average, Cones-AdiabT1ρ increased 3.6-fold from 13.6 ± 1.5 ms at 0° to 48.4 ± 5.4 ms at 55°, Cones-CW-T1ρ increased 6.1-fold from 7.0 ± 1.1 ms at 0° to 42.6 ± 5.2 ms at 55°, and Cones-T2* increased 12.3-fold from 2.9 ± 0.5 ms at 0° to 35.8 ± 6.4 ms at 55°. Although Cones-AdiabT1ρ is still subject to significant angular dependence, it shows a much-reduced magic angle effect compared to Cones-CW-T1ρ and Cones-T2 *, and may be used as a novel and potentially more effective approach for quantitative evaluation of the Achilles tendon and other MSK tissues.
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Affiliation(s)
- Mei Wu
- Department of Radiology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong, China
- Department of Radiology, University of California, San Diego, CA, US
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, CA, US
| | - Lidi Wan
- Department of Radiology, University of California, San Diego, CA, US
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, CA, US
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA, US
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA, US
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, US
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA, US
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21
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Krämer M, Kollert MR, Brisson NM, Maggioni MB, Duda GN, Reichenbach JR. Immersion of Achilles tendon in phosphate-buffered saline influences T 1 and T 2 * relaxation times: An ex vivo study. NMR Biomed 2020; 33:e4288. [PMID: 32141159 DOI: 10.1002/nbm.4288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/04/2020] [Accepted: 02/18/2020] [Indexed: 06/10/2023]
Abstract
Robust mapping of relaxation parameters in ex vivo tissues is based on hydration and therefore requires control of the tissue treatment to ensure tissue integrity and consistent measurement conditions over long periods of time. One way to maintain the hydration of ex vivo tendon tissue is to immerse the samples in a buffer solution. To this end, various buffer solutions have been proposed; however, many appear to influence the tissue relaxation times, especially with prolonged exposure. In this work, ovine Achilles tendon tissue was used as a model to investigate the effect of immersion in phosphate-buffered saline (PBS) and the effects on the T1 and T2* relaxation times. Ex vivo samples were measured at 0 (baseline), 30 and 67 hours after immersion in PBS. Ultrashort echo time (UTE) imaging was performed using variable flip angle and echo train-shifted multi-echo imaging for T1 and T2* estimation, respectively. Compared with baseline, both T1 and T2* relaxation time constants increased significantly after 30 hours of immersion. T2* continued to show a significant increase between 30 and 67 hours. Both T1 and T2* tended to approach saturation at 67 hours. These results exemplify the relevance of stringently controlled tissue preparation and preservation techniques, both before and during MRI experiments.
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Affiliation(s)
- Martin Krämer
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Matthias R Kollert
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health Center for Regenerative Therapies (BIH), Berlin, Germany
- Berlin-Brandenburg School for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Nicholas M Brisson
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Marta B Maggioni
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Georg N Duda
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health Center for Regenerative Therapies (BIH), Berlin, Germany
- Berlin-Brandenburg School for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jürgen R Reichenbach
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
- Michael Stifel Center Jena for Data-driven and Simulation Science, Friedrich-Schiller-University Jena, Germany
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22
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Wu M, Ma YJ, Kasibhatla A, Chen M, Jang H, Jerban S, Chang EY, Du J. Convincing evidence for magic angle less-sensitive quantitative T 1ρ imaging of articular cartilage using the 3D ultrashort echo time cones adiabatic T 1ρ (3D UTE cones-AdiabT 1ρ ) sequence. Magn Reson Med 2020; 84:2551-2560. [PMID: 32419199 DOI: 10.1002/mrm.28317] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 01/27/2023]
Abstract
PURPOSE To investigate the magic angle effect in three-dimensional ultrashort echo time Cones Adiabatic T1ρ (3D UTE Cones-AdiabT1ρ ) imaging of articular cartilage at 3T. METHODS The magic angle effect was investigated by repeated 3D UTE Cones-AdiabT1ρ imaging of eight human patellar samples at five angular orientations ranging from 0° to 90° relative to the B0 field. Cones continuous wave T1ρ (Cones-CW-T1ρ ) and Cones- T 2 ∗ sequences were also applied for comparison. Cones-AdiabT1ρ , Cones-CW-T1ρ and Cones- T 2 ∗ values were measured for four regions of interest (ROIs) (10% superficial layer, 60% transitional layer, 30% radial layer, and a global ROI) for each sample at each orientation to evaluate their angular dependence. RESULTS 3D UTE Cones-AdiabT1ρ values increased from the radial layer to the superficial layer for all angular orientations. The superficial layer showed the least angular dependence (around 4.4%), while the radial layer showed the strongest angular dependence (around 34.4%). Cones-AdiabT1ρ values showed much reduced magic angle effect compared to Cones-CW-T1ρ and Cones- T 2 ∗ values for all four ROIs. On average over eight patellae, Cones-AdiabT1ρ values increased by 27.2% (4.4% for superficial, 23.8% for transitional, and 34.4% for radial layers), Cones-CW-T1ρ values increased by 76.9% (11.3% for superficial, 59.1% for transitional, and 117.8% for radial layers), and Cones- T 2 ∗ values increased by 237.5% (87.9% for superficial, 262.9% for transitional, and 327.3% for radial layers) near the magic angle. CONCLUSIONS The 3D UTE Cones-AdiabT1ρ sequence is less sensitive to the magic angle effect in the evaluation of articular cartilage compared to Cones- T 2 ∗ and Cones-CW-T1ρ .
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Affiliation(s)
- Mei Wu
- Department of Radiology, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong, China.,Department of Radiology, University of California San Diego, San Diego, California, USA
| | - Ya-Jun Ma
- Department of Radiology, University of California San Diego, San Diego, California, USA
| | - Akhil Kasibhatla
- Department of Radiology, University of California San Diego, San Diego, California, USA
| | - Mingxin Chen
- Department of Radiology, University of California San Diego, San Diego, California, USA
| | - Hyungseok Jang
- Department of Radiology, University of California San Diego, San Diego, California, USA
| | - Saeed Jerban
- Department of Radiology, University of California San Diego, San Diego, California, USA
| | - Eric Y Chang
- Department of Radiology, University of California San Diego, San Diego, California, USA.,Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, California, USA
| | - Jiang Du
- Department of Radiology, University of California San Diego, San Diego, California, USA
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23
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Ma YJ, Chen Y, Li L, Cai Z, Wei Z, Jerban S, Jang H, Chang EY, Du J. Trabecular bone imaging using a 3D adiabatic inversion recovery prepared ultrashort TE Cones sequence at 3T. Magn Reson Med 2020; 83:1640-1651. [PMID: 31631404 PMCID: PMC6982597 DOI: 10.1002/mrm.28027] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 09/02/2019] [Accepted: 09/12/2019] [Indexed: 12/21/2022]
Abstract
PURPOSE To investigate direct imaging of trabecular bone using a 3D adiabatic inversion recovery prepared ultrashort TE cones (3D IR-UTE-Cones) sequence. METHODS The proposed 3D IR-UTE-Cones sequence used a broadband adiabatic inversion pulse together with a short TR/TI combination to suppress signals from long T2 tissues such as muscle and marrow fat, followed by multispoke UTE acquisition to detect signal from short T2 water components in trabecular bone. The feasibility of this technique for robust suppression of long T2 tissues was first demonstrated through numerical simulations. The proposed IR-UTE-Cones sequence was applied to a hip agarose bone phantom and to 6 healthy volunteers for morphologic and quantitative T 2 ∗ and proton density mapping of trabecular bone. RESULTS Numeric simulation suggests that the IR technique with a short TR/TI combination provides sufficient suppression of long T2 tissues with a wide range of T1 s. High contrast imaging of trabecular bone can be achieved ex vivo and in vivo, with fitted T 2 ∗ values of 0.3-0.45 ms and proton densities of 5-9 mol/L. CONCLUSION The 3D IR-UTE-Cones sequence with a short TR/TI combination provides robust suppression of long T2 tissues and allows both selective imaging and quantitative ( T 2 ∗ and proton density) assessment of short T2 water components in trabecular bone in vivo.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, CA
| | - Yanjun Chen
- Department of Radiology, University of California, San Diego, CA
| | - Liang Li
- Department of Radiology, University of California, San Diego, CA
| | - Zhenyu Cai
- Department of Radiology, University of California, San Diego, CA
| | - Zhao Wei
- Department of Radiology, University of California, San Diego, CA
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, CA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA
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24
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Ashir A, Ma Y, Jerban S, Jang H, Wei Z, Le N, Du J, Chang EY. Rotator Cuff Tendon Assessment in Symptomatic and Control Groups Using Quantitative MRI. J Magn Reson Imaging 2020; 52:864-872. [PMID: 32129560 DOI: 10.1002/jmri.27115] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/14/2020] [Accepted: 02/18/2020] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Relatively weak correlations between patient symptoms and rotator cuff tendon (RCT) tearing have been reported; however, the relationship between symptoms and tendinosis has been less well-studied. PURPOSE/HYPOTHESIS To use quantitative MRI to assess the bilateral RCTs in shoulders of both patients with unilateral symptomatic tendinopathy and control subjects. We hypothesized that quantitative MRI measures would differ between symptomatic patients and controls. STUDY TYPE Prospective imaging study. POPULATION/SUBJECTS In all, 48 shoulders from 24 subjects (mean age, 32.8 years), including 14 patients with unilateral symptomatic tendinopathy and 10 asymptomatic controls. FIELD STRENGTH/SEQUENCE 3T/3D ultrashort echo time Cones sequence with magnetization transfer preparation (UTE-Cones-MT) and Carr-Purcell-Meiboom-Gill. ASSESSMENT Macromolecular fraction (MMF) and T2 relaxation were measured in four regions of the superior RCT, including all-segments, and lateral-third, bursal-sided, and articular-sided segments. The Western Ontario Rotator Cuff (WORC) index and visual analog scale were assessed. STATISTICAL TESTS Three shoulder groups were evaluated, including symptomatic shoulders, contralateral asymptomatic shoulders in patients, and asymptomatic controls. MMF and T2 values were compared between groups using a bootstrap-based comparison of means. RESULTS Significant differences were found in both MMF and T2 values between symptomatic and control RCTs when analyzing all-segments (P = 0.027 and P = 0.006, respectively) and articular-sided segments (both P = 0.001). Significant differences between asymptomatic RCTs in patients and control RCTs were also found, including MMF in all four anatomic regions analyzed (P = 0.024-0.044), as well as T2 in all-segments (P = 0.003), bursal-sided segments (P = 0.021), and articular-sided segments (P = 0.002). No significant differences in MMF (P = 0.420-0.950) or T2 (P = 0.380-0.910) were seen between ipsilateral symptomatic and contralateral asymptomatic RCTs in patients. DATA CONCLUSION Symptomatic RCTs showed significantly lower MMF values and higher T2 values compared with control RCTs. In patients with unilateral symptomatic tendinopathy, the contralateral shoulder can demonstrate asymptomatic tendinopathy, which can be quantified using MMF or T2 . EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2. J. Magn. Reson. Imaging 2020;52:864-872.
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Affiliation(s)
- Aria Ashir
- Department of Radiology, University of California, San Diego, California, USA.,Research Service, VA San Diego Healthcare System, San Diego, California, USA.,College of Medicine, Drexel University, Philadelphia, Pennsylvania, USA
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, California, USA
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, California, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, California, USA
| | - Zhao Wei
- Department of Radiology, University of California, San Diego, California, USA
| | - Nicole Le
- Research Service, VA San Diego Healthcare System, San Diego, California, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, California, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, California, USA.,Research Service, VA San Diego Healthcare System, San Diego, California, USA
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25
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Jerban S, Lu X, Dorthe EW, Alenezi S, Ma Y, Kakos L, Jang H, Sah RL, Chang EY, D’Lima D, Du J. Correlations of cortical bone microstructural and mechanical properties with water proton fractions obtained from ultrashort echo time (UTE) MRI tricomponent T2* model. NMR Biomed 2020; 33:e4233. [PMID: 31820518 PMCID: PMC7161421 DOI: 10.1002/nbm.4233] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/31/2019] [Accepted: 11/06/2019] [Indexed: 05/12/2023]
Abstract
Mechanical and microstructural evaluations of cortical bone using ultrashort echo time magnetic resonance imaging (UTE-MRI) have been performed increasingly in recent years. UTE-MRI acquires considerable signal from cortical bone and enables quantitative bone evaluations. Fitting bone apparent transverse magnetization (T2*) decay using a bicomponent model has been regularly performed to estimate bound water (BW) and pore water (PW) in the quantification of bone matrix and porosity, respectively. Human cortical bone possesses a considerable amount of fat, which appears as MRI T2* signal oscillation and can subsequently lead to BW overestimation when using a bicomponent model. Tricomponent T2* fitting model has been developed to improve BW and PW estimations by accounting for fat contribution in the MRI signal. This study aimed to investigate the correlations of microstructural and mechanical properties of human cortical bone with water pool fractions obtained from a tricomponent T2* model. 135 cortical bone strips (~4 × 2 × 40 mm3 ) from tibial and femoral midshafts of 37 donors (61 ± 24 years old) were scanned using ten sets of dual-echo 3D-UTE-Cones sequences (TE = 0.032-24.0 ms) on a 3 T MRI scanner for T2* fitting analyses. Average bone porosity and pore size were measured using microcomputed tomography (μCT) at 9 μm voxel size. Bone mechanical properties were measured using 4-point bending tests. Using a tricomponent model, bound water fraction (FracBW ) showed significant strong (R = 0.70, P < 0.01) and moderate (R = 0.58-0.62, P < 0.01) correlations with porosity and mechanical properties, respectively. Correlations of bone microstructural and mechanical properties with water pool fractions were higher for tricomponent model results compared with the bicomponent model. The tricomponent T2* fitting model is suggested as a useful technique for cortical bone evaluation where the MRI contribution of bone fat is accounted for.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Corresponding authors: • Jiang Du, Department of Radiology, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA, , Phone: +1 858 246 2248, Fax: +1 888 960 5922, • Saeed Jerban, Department of Radiology, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA, , Phone: +1 858 246 3158, Fax: +1 888 960 5922
| | - Xing Lu
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- 12Sigma Technologies, San Diego, CA, USA
| | - Erik W. Dorthe
- Shiley Center for Orthopedic Research and Education at Scripps Clinic, La Jolla, CA, USA
| | - Salem Alenezi
- Research and Laboratories Sector, Saudi Food and Drug Authority, Riyadh, KSA
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Lena Kakos
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
| | - Robert L. Sah
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA, USA
| | - Eric Y. Chang
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, La Jolla, CA, USA
| | - Darryl D’Lima
- Shiley Center for Orthopedic Research and Education at Scripps Clinic, La Jolla, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, La Jolla, CA, USA
- Corresponding authors: • Jiang Du, Department of Radiology, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA, , Phone: +1 858 246 2248, Fax: +1 888 960 5922, • Saeed Jerban, Department of Radiology, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA, , Phone: +1 858 246 3158, Fax: +1 888 960 5922
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Wu M, Zhao W, Wan L, Kakos L, Li L, Jerban S, Jang H, Chang EY, Du J, Ma YJ. Quantitative three-dimensional ultrashort echo time cones imaging of the knee joint with motion correction. NMR Biomed 2020; 33:e4214. [PMID: 31713936 PMCID: PMC7197345 DOI: 10.1002/nbm.4214] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 10/01/2019] [Accepted: 10/18/2019] [Indexed: 05/16/2023]
Abstract
Knee degeneration involves all the major tissues in the joint. However, conventional MRI sequences can only detect signals from long T2 tissues such as the superficial cartilage, with little signal from the deep cartilage, menisci, ligaments, tendons and bone. It is highly desirable to develop new sequences that can detect signal from all major tissues in the knee. We aimed to develop a comprehensive quantitative three-dimensional ultrashort echo time (3D UTE) cones imaging protocol for a truly "whole joint" evaluation of knee degeneration. The protocol included 3D UTE cones actual flip angle imaging (3D UTE-Cones-AFI) for T1 mapping, multiecho UTE-Cones with fat suppression for T2 * mapping, UTE-Cones with adiabatic T1ρ (AdiabT1ρ ) preparation for AdiabT1ρ mapping, and UTE-Cones magnetization transfer (UTE-Cones-MT) for MT ratio (MTR) and modeling of macromolecular proton fraction (f). An elastix registration technique was used to compensate for motion during scans. Quantitative data analyses were performed on the registered data. Three knee specimens and 15 volunteers were evaluated at 3 T. The elastix motion correction algorithm worked well in correcting motion artifacts associated with relatively long scan times. Much improved curve fitting was achieved for all UTE-Cones biomarkers with greatly reduced root mean square errors. The averaged T1 , T2 *, AdiabT1ρ , MTR and f for knee joint tissues of 15 healthy volunteers were reported. The 3D UTE-Cones quantitative imaging techniques (ie, T1 , T2 *, AdiabT1ρ , MTR and MT modeling) together with elastix motion correction provide robust volumetric measurement of relaxation times, MTR and f of both short and long T2 tissues in the knee joint.
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Affiliation(s)
- Mei Wu
- Department of Radiology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong, China
- Department of Radiology, University of California, San Diego, CA, US
| | - Wei Zhao
- Department of Radiology, University of California, San Diego, CA, US
| | - Lidi Wan
- Department of Radiology, University of California, San Diego, CA, US
| | - Lena Kakos
- Department of Radiology, University of California, San Diego, CA, US
| | - Liang Li
- Department of Radiology, University of California, San Diego, CA, US
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, CA, US
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA, US
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA, US
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, US
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA, US
| | - Ya-Jun Ma
- Department of Radiology, University of California, San Diego, CA, US
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Ma YJ, Jerban S, Jang H, Chang EY, Du J. Fat suppression for ultrashort echo time imaging using a novel soft-hard composite radiofrequency pulse. Magn Reson Med 2019; 82:2178-2187. [PMID: 31317565 DOI: 10.1002/mrm.27885] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 06/05/2019] [Accepted: 06/07/2019] [Indexed: 12/19/2022]
Abstract
PURPOSE To design a soft-hard composite pulse for fat suppression and water excitation in ultrashort echo time (UTE) imaging with minimal short T2 signal attenuation. METHODS The composite pulse contains a narrow bandwidth soft pulse centered on the fat peak with a small negative flip angle (-α) and a short rectangular pulse with a small positive flip angle (α). The fat magnetization experiences both tipping-down and -back with an identical flip angle and thus returns to the equilibrium state, leaving only the excited water magnetization. Bloch simulations, as well as knee, tibia, and ankle UTE imaging studies, were performed to investigate the effectiveness of fat suppression and corresponding water signal attenuation. A conventional fat saturation (FatSat) module was used for comparison. Signal suppression ratio (SSR), defined as the ratio of signal difference between non-fat-suppression and fat-suppression images over the non-fat-suppression signal, was introduced to evaluate the efficiency of the composite pulse. RESULTS Numerical simulations demonstrate that the soft-hard pulse has little saturation effect on short T2 water signals. Knee, tibia, and ankle UTE imaging results suggest that comparable fat suppression can be achieved with the soft-hard pulse and the FatSat module. However, much less water saturation is induced by the soft-hard pulse, especially for short T2 tissues, with SSRs reduced from 71.8 ± 6.9% to 5.8 ± 4.4% for meniscus, from 68.7 ± 5.5% to 7.7 ± 7.6% for bone, and from 62.9 ± 12.0% to 4.8 ± 3.2% for the Achilles tendon. CONCLUSION The soft-hard composite pulse can suppress fat signals in UTE imaging with little signal attenuation on short T2 tissues.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, California
| | - Saeed Jerban
- Department of Radiology, University of California, San Diego, California
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, California
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, California.,Radiology Service, VA San Diego Healthcare System, San Diego, California
| | - Jiang Du
- Department of Radiology, University of California, San Diego, California
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28
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Knobloch G, Colgan T, Schiebler ML, Johnson KM, Li G, Schubert T, Reeder SB, Nagle SK. Comparison of gadolinium-enhanced and ferumoxytol-enhanced conventional and UTE-MRA for the depiction of the pulmonary vasculature. Magn Reson Med 2019; 82:1660-1670. [PMID: 31228293 DOI: 10.1002/mrm.27853] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 05/01/2019] [Accepted: 05/20/2019] [Indexed: 12/28/2022]
Abstract
PURPOSE To evaluate the feasibility of ferumoxytol (FE)-enhanced UTE-MRA for depiction of the pulmonary vascular and nonvascular structures. METHODS Twenty healthy volunteers underwent contrast-enhanced pulmonary MRA at 3 T during 2 visits, separated by at least 4 weeks. Visit 1: The MRA started with a conventional multiphase 3D T1 -weighted breath-held spoiled gradient-echo MRA before and after the injection of 0.1 mmol/kg gadobenate dimeglumine (GD). Subsequently, free-breathing GD-UTE-MRA was acquired as a series of 3 flip angles (FAs) (6°, 12°, 18°) to optimize T1 weighting. Visit 2: After the injection of 4 mg/kg FE, MRA was performed during the steady state, starting with a conventional 3D T1 -weighted breath-held spoiled gradient-echo MRA and followed by free-breathing FE-UTE-MRA, both at 4 different FAs (6°, 12°, 18°, 24°). The optimal FA for best T1 contrast was evaluated. Image quality at the optimal FA was compared between methods on a 4-point ordinal scale, using multiphase GD conventional pulmonary MRA (cMRA) as standard of reference. RESULTS Flip angle in the range of 18°-24° resulted in best T1 contrast for FE cMRA and both UTE-MRA techniques (p > .05). At optimized FA, image quality of the vasculature was good/excellent with both FE-UTE-MRA and GD cMRA (98% versus 97%; p = .51). Both UTE techniques provided superior depiction of nonvascular structures compared with either GD-enhanced or FE-enhanced cMRA (p < .001). However, GD-UTE-MRA showed the lowest image quality of the angiogram due to low image contrast. CONCLUSION Free-breathing UTE-MRA using FE is feasible for simultaneous assessment of the pulmonary vasculature and nonvascular structures. Patient studies should investigate the clinical utility of free-breathing UTE-MRA for assessment of pulmonary emboli.
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Affiliation(s)
- Gesine Knobloch
- Department of Radiology, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Radiology, Charité University Hospital, Berlin, Germany
| | - Timothy Colgan
- Department of Radiology, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin
| | - Mark L Schiebler
- Department of Radiology, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin
| | - Kevin M Johnson
- Department of Radiology, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Medical Physics, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin
| | - Geng Li
- Department of Biostatistics and Medical Informatics, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin
| | - Tilman Schubert
- Department of Radiology, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Neuroradiology, Zurich University Hospital, Zurich, Switzerland
| | - Scott B Reeder
- Department of Radiology, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Medical Physics, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Biomedical Engineering, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Medicine, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Emergency Medicine, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin
| | - Scott K Nagle
- Department of Radiology, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Medical Physics, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin.,Department of Pediatrics, University of Wisconsin-School of Medicine and Public Health, Madison, Wisconsin
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29
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Li Q, Cao X, Ye H, Liao C, He H, Zhong J. Ultrashort echo time magnetic resonance fingerprinting (UTE-MRF) for simultaneous quantification of long and ultrashort T 2 tissues. Magn Reson Med 2019; 82:1359-1372. [PMID: 31131911 DOI: 10.1002/mrm.27812] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 03/27/2019] [Accepted: 04/22/2019] [Indexed: 12/12/2022]
Abstract
PURPOSE To demonstrate an ultrashort echo time magnetic resonance fingerprinting (UTE-MRF) method that allows quantifying relaxation times for muscle and bone in the musculoskeletal system and generating bone enhanced images that mimic CT scans. METHODS A fast imaging steady-state free precession MRF sequence with half pulse excitation and half projection readout was designed to sample fast T2 decay signals. Varying echo time (TE) of a sinusoidal pattern was applied to enhance sensitivity for tissues with short and ultrashort T2 values. The performance of UTE-MRF was evaluated via simulations, phantom, and in vivo experiments. RESULTS A minimal TE of 0.05 ms was achieved. Simulations indicated the sinusoidal TE sampling increased T2 quantification accuracy in the cortical bone and tendon but had little impact on long T2 muscle quantifications. For the rubber phantom, the averaged relaxometries from UTE-MRF (T1 = 162 ms and T2 = 1.07 ms) compared well with the gold standard (T1 = 190 ms and T 2 ∗ = 1.03 ms). For the long T2 agarose phantom, the linear regression slope between UTE-MRF and gold standard was 1.07 (R2 = 0.991) for T1 and 1.04 (R2 = 0.994) for T2 . In vivo experiments showed the detection of the cortical bone (averaged T2 = 1.0 ms) and Achilles tendon (averaged T2 = 15 ms). Scalp structures from the bone enhanced image show high similarity with CT. CONCLUSION The UTE-MRF with sinusoidal TEs can simultaneously quantify T1 , T2 , proton density, and B0 in long, short, even ultrashort T2 musculoskeletal structures. Bone enhanced images can be achieved in the brain with UTE-MRF.
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Affiliation(s)
- Qing Li
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiaozhi Cao
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China
| | - Huihui Ye
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, China
| | - Congyu Liao
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China
| | - Hongjian He
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jianhui Zhong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China
- Department of Imaging Sciences, University of Rochester, Rochester, New York
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30
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Ma YJ, Zhao W, Wan L, Guo T, Searleman A, Jang H, Chang EY, Du J. Whole knee joint T 1 values measured in vivo at 3T by combined 3D ultrashort echo time cones actual flip angle and variable flip angle methods. Magn Reson Med 2019; 81:1634-1644. [PMID: 30443925 PMCID: PMC6347520 DOI: 10.1002/mrm.27510] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 07/06/2018] [Accepted: 08/07/2018] [Indexed: 02/06/2023]
Abstract
PURPOSE To measure T1 relaxations for the major tissues in whole knee joints on a clinical 3T scanner. METHODS The 3D UTE-Cones actual flip angle imaging (AFI) method was used to map the transmission radiofrequency field (B1 ) in both short and long T2 tissues, which was then used to correct the 3D UTE-Cones variable flip angle (VFA) fitting to generate accurate T1 maps. Numerical simulation was carried out to investigate the accuracy of T1 measurement for a range of T2 values, excitation pulse durations, and B1 errors. Then, the 3D UTE-Cones AFI-VFA method was applied to healthy volunteers (N = 16) to quantify the T1 of knee tissues including cartilage, meniscus, quadriceps tendon, patellar tendon, anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), marrow, and muscles at 3T. RESULTS Numerical simulation showed that the 3D UTE-Cones AFI-VFA technique can provide accurate T1 measurements (error <1%) when the tissue T2 is longer than 1 ms and a 150 μs excitation RF pulse is used and therefore is suitable for most knee joint tissues. The proposed 3D UTE-Cones AFI-VFA method showed an average T1 of 1098 ± 67 ms for cartilage, 833 ± 47 ms for meniscus, 800 ± 66 ms for quadriceps tendon, 656 ± 43 ms for patellar tendon, 873 ± 38 ms for ACL, 832 ± 49 ms for PCL, 379 ± 18 ms for marrow, and 1393 ± 46 ms for muscles. CONCLUSION The 3D UTE-Cones AFI-VFA method allows volumetric T1 measurement of the major tissues in whole knee joints on a clinical 3T scanner.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, CA
| | - Wei Zhao
- Department of Radiology, University of California, San Diego, CA
| | - Lidi Wan
- Department of Radiology, University of California, San Diego, CA
| | - Tan Guo
- Department of Radiology, University of California, San Diego, CA
| | - Adam Searleman
- Department of Radiology, University of California, San Diego, CA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA
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31
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Bird L, D'Souza A, Ball I, Rae C, Herbert RD, Bolsterlee B. Validity and reliability of measurements of aponeurosis dimensions from magnetic resonance images. Scand J Med Sci Sports 2019; 29:808-815. [PMID: 30746780 DOI: 10.1111/sms.13407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 02/04/2019] [Indexed: 11/29/2022]
Abstract
Muscle performance is closely related to the structure and function of tendons and aponeuroses, the sheet-like, intramuscular parts of tendons. The architecture of aponeuroses has been difficult to study with magnetic resonance imaging (MRI) because these thin, collagen-rich connective tissues have very short transverse relaxation (T2) times and therefore provide a weak signal with conventional MRI sequences. Here, we validated measurements of aponeurosis dimensions from two MRI sequences commonly used in muscle-tendon research (mDixon and T1-weighted images), and an ultrashort echo time (UTE) sequence designed for imaging tissues with short T2 times. MRI-based measurements of aponeurosis width, length, and area of 20 sheep leg muscles were compared to direct measurements made with three-dimensional (3D) quantitative microdissection. The errors in measurement of aponeurosis width relative to the mean width were 1.8% for UTE, 3.7% for T1, and 18.8% for mDixon. For aponeurosis length, the errors were 7.6% for UTE, 1.9% for T1, and 21.0% for mDixon. Measurements from T1 and UTE scans were unbiased, but mDixon scans systematically underestimated widths, lengths, and areas of the aponeuroses. Using the same methods, we then found high inter-rater reliability (intraclass correlation coefficients >0.92 for all measures) of measurements of the dimensions of the central aponeurosis of the human tibialis anterior muscle from T1-weighted scans. We conclude that valid and reliable measurements of aponeurosis dimensions can be obtained from UTE and from T1-weighted scans. When the goal is to study the macroscopic architecture of aponeuroses, UTE does not hold an advantage over T1-weighted imaging.
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Affiliation(s)
- Lachlan Bird
- Neuroscience Research Australia, Sydney, New South Wales, Australia.,University of Sydney, Sydney, New South Wales, Australia
| | - Arkiev D'Souza
- Neuroscience Research Australia, Sydney, New South Wales, Australia.,University of New South Wales, Sydney, New South Wales, Australia
| | - Iain Ball
- Philips Australia & New Zealand, Sydney, New South Wales, Australia
| | - Caroline Rae
- Neuroscience Research Australia, Sydney, New South Wales, Australia.,University of New South Wales, Sydney, New South Wales, Australia
| | - Robert D Herbert
- Neuroscience Research Australia, Sydney, New South Wales, Australia.,University of New South Wales, Sydney, New South Wales, Australia
| | - Bart Bolsterlee
- Neuroscience Research Australia, Sydney, New South Wales, Australia.,University of New South Wales, Sydney, New South Wales, Australia
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32
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Jerban S, Ma Y, Wan L, Searleman AC, Jang H, Sah RL, Chang EY, Du J. Collagen proton fraction from ultrashort echo time magnetization transfer (UTE-MT) MRI modelling correlates significantly with cortical bone porosity measured with micro-computed tomography (μCT). NMR Biomed 2019; 32:e4045. [PMID: 30549338 PMCID: PMC6324959 DOI: 10.1002/nbm.4045] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/29/2018] [Accepted: 10/30/2018] [Indexed: 05/08/2023]
Abstract
Intracortical bone porosity is a key microstructural parameter that determines bone mechanical properties. While clinical MRI visualizes the cortical bone with a signal void, ultrashort echo time (UTE) MRI can acquire high signal from cortical bone, thus enabling quantitative assessments. Magnetization transfer (MT) imaging combined with UTE-MRI can indirectly assess protons in the bone collagenous matrix, which are inversely related to porosity. This study aimed to examine UTE-MT MRI techniques to evaluate intracortical bone porosity. Eighteen human cortical bone specimens from the tibial and fibular midshafts were scanned using UTE-MT sequences on a clinical 3 T MRI scanner and on a high-resolution micro-computed tomography (μCT) scanner. A series of MT pulse saturation powers (500°, 1000°, 1500°) and frequency offsets (2, 5, 10, 20, 50 kHz) were used to measure the macromolecular fraction (MMF) and macromolecular T2 (T2MM ) using a two-pool MT model. The measurements were made on 136 different regions of interest (ROIs). ROIs were selected at three cortical bone layers (from endosteum to periosteum) and four anatomical sites (anterior, mid-medial, mid-lateral, and posterior) to provide a wide range of porosity. MMF showed moderate to strong correlations with intracortical bone porosity (R = -0.67 to -0.73, p < 0.01) and bone mineral density (BMD) (R = +0.46 to +0.70, p < 0.01). Comparing the average MMF between cortical bone layers revealed a significant increase from the endosteum towards the periosteum. Such a pattern was in agreement with porosity reduction and BMD increase towards the periosteum. These results suggest that the two-pool UTE-MT technique can potentially serve as a novel and accurate tool to assess intracortical bone porosity.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, San Diego, CA, USA
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, CA, USA
| | - Lidi Wan
- Department of Radiology, University of California, San Diego, CA, USA
| | - Adam C. Searleman
- Department of Radiology, University of California, San Diego, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, San Diego, CA, USA
| | - Robert L. Sah
- Department of Bioengineering, University of California, San Diego, CA, USA
- Department of Orthopaedic Surgery, University of California, San Diego, CA, USA
| | - Eric Y. Chang
- Department of Radiology, University of California, San Diego, CA, USA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA, USA
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33
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Chen B, Cheng X, Dorthe EW, Zhao Y, D'Lima D, Bydder GM, Liu S, Du J, Ma YJ. Evaluation of normal cadaveric Achilles tendon and enthesis with ultrashort echo time (UTE) magnetic resonance imaging and indentation testing. NMR Biomed 2019; 32:e4034. [PMID: 30457179 DOI: 10.1002/nbm.4034] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/14/2018] [Accepted: 10/08/2018] [Indexed: 06/09/2023]
Abstract
Entheses are regions where tendons and ligaments attach to bone, and are the primary target in seronegative and other diseases of the musculoskeletal (MSK) system. MRI has been widely used for visualizing features of inflammatory and degenerative MSK disease; however, normal tendons and entheses have short transverse relaxation times (T2 ), and show little or no signal with conventional clinical MRI pulse sequences, making it difficult to investigate their MR properties. In this study we examined the normal MR morphology of the cadaveric Achilles tendon and enthesis at 3 T using novel three-dimensional ultrashort echo time (3D UTE) Cones sequences, and at 11.7 T using conventional MRI sequences. We also studied the MR properties of the Achilles tendon and enthesis including T2 *, T1 , and magnetization transfer ratio (MTR). In addition, MT modeling of macromolecular proton fractions was investigated using 3D UTE Cones sequences at 3 T. Indentation testing was performed to investigate the mechanical properties of the tendons and entheses, and this was followed by histological examination. In total five specimens (<50 years) were investigated. On average, tendons and entheses respectively had T2 * values of 0.93 ± 0.48 ms and 2.77 ± 0.79 ms, T1 values of 644 ± 22 ms and 780 ± 55 ms, MTRs of 0.373 ± 0.03 and 0.244 ± 0.009 with an MT power of 1000° and frequency offset of 2 kHz, and macromolecular proton fractions of 18.0 ± 2.2% and 13.9 ± 1.9%. Compared with the tendon, the enthesis generally had a longer T2 *, a longer T1 , a lower MTR, and a lower macromolecular proton fraction as well as both a higher Young's modulus and stiffness. Results from this study are likely to provide a useful baseline for identifying deviations from the normal in seronegative arthritis and other disease of the entheses.
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Affiliation(s)
- Bimin Chen
- Department of Radiology, The First Affiliated Hospital of Jinan University, Guangzhou, China
- Department of Radiology, University of California, San Diego, CA, USA
| | - Xin Cheng
- Department of Radiology, University of California, San Diego, CA, USA
- Department of Histology and Embryology, Medical School, Jinan University, Guangzhou, China
| | - Erik W Dorthe
- Shiley Center for Orthopedic Research and Education at Scripps Clinic, La Jolla, CA, USA
| | - Yinghua Zhao
- Department of Radiology, University of California, San Diego, CA, USA
| | - Darryl D'Lima
- Shiley Center for Orthopedic Research and Education at Scripps Clinic, La Jolla, CA, USA
| | - Graeme M Bydder
- Department of Radiology, University of California, San Diego, CA, USA
| | - Sirun Liu
- Department of Radiology, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA, USA
| | - Ya-Jun Ma
- Department of Radiology, University of California, San Diego, CA, USA
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34
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Abstract
The objectives of this study were to compare the ultrashort T2* relaxation time with the T2* relaxation time using the 3 dimensional (3D) cones sequence in 3 groups of patients with normal, degenerated, and torn knee menisci, and to demonstrate the additional effect of the ultrashort echo time (UTE) signal intensity.Following institutional review board approval, 42 knee magnetic resonance imaging (MRI) scans of 42 patients who presented with knee pain and underwent knee MRIs, with the 3D Cones of UTE sequence (minimum TEs: 32 μs) and a 3T MRI scanner (Discovery 750, GE Healthcare, Waukesha, WI), were analyzed. The enrolled patients were classified into 3 subgroups:normal meniscus on conventional MRI, with no positive meniscus-related physical examination in medical records;meniscal degeneration with signal changes on conventional MRI; andmeniscal tear.For the quantitative assessment, the mean values inside user-drawn regions of interest (ROIs) of the medial menisci were drawn on UTE T2* map and T2* map. For statistical analyses, 1-way analysis of variance (ANOVA) with post-hoc analysis using the Tukey HSD test was conducted to compare groups, and effect size was used to compare the discrimination power.The ultrashort T2* relaxation times were higher in patients with meniscal tear than in those with normal and degeneration groups (P <.05, respectively) whereas T2* relaxation times were not statistically significantly different. The ultrashort T2* relaxation times showed higher effect sizes than the T2* times between tear and normal/degeneration.The ultrashort T2* relaxation times showed better delineation of meniscal degeneration or tears than T2* relaxation times. The ultrashort T2* relaxation times could be more sensitive at differentiating between normal and pathologic meniscal conditions in patients.
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Affiliation(s)
- Jisook Yi
- Department of Radiology, Research Institute of Radiological Science, YUHS-KRIBB, Medical Convergence Research Institute, and Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul
- Department of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Republic of Korea
| | - Young Han Lee
- Department of Radiology, Research Institute of Radiological Science, YUHS-KRIBB, Medical Convergence Research Institute, and Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul
| | - Ho-Taek Song
- Department of Radiology, Research Institute of Radiological Science, YUHS-KRIBB, Medical Convergence Research Institute, and Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul
| | - Jin-Suck Suh
- Department of Radiology, Research Institute of Radiological Science, YUHS-KRIBB, Medical Convergence Research Institute, and Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul
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Tipirneni-Sajja A, Loeffler RB, Krafft AJ, Sajewski AN, Ogg RJ, Hankins JS, Hillenbrand CM. Ultrashort echo time imaging for quantification of hepatic iron overload: Comparison of acquisition and fitting methods via simulations, phantoms, and in vivo data. J Magn Reson Imaging 2018; 49:1475-1488. [PMID: 30358001 DOI: 10.1002/jmri.26325] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 08/13/2018] [Accepted: 08/13/2018] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Current R2*-MRI techniques for measuring hepatic iron content (HIC) use various acquisition types and fitting models. PURPOSE To evaluate the accuracy and precision of R2*-HIC acquisition and fitting methods. STUDY TYPE Signal simulations, phantom study, and prospective in vivo cohort. POPULATION In all, 132 patients (58/74 male/female, mean age 17.7 years). FIELD STRENGTH/SEQUENCE 2D-multiecho gradient-echo (GRE) and ultrashort echo time (UTE) acquisitions at 1.5T. ASSESSMENT Synthetic MR signals were created to mimic published GRE and UTE methods, using different R2* values (25-2000 s-1 ) and signal-to-noise ratios (SNR). Phantoms with varying iron concentrations were scanned at 1.5T. In vivo data were analyzed from 132 patients acquired at 1.5T. R2* was estimated by fitting using three signal models. Accuracy and precision of R2* measurements for UTE acquisition parameters (SNR, echo spacing [ΔTE], maximum echo time [TEmax ]) and fitting methods were compared for simulated, phantom, and in vivo datasets. STATISTICAL TESTS R2* accuracy was determined from the relative error and by linear regression analysis. Precision was evaluated using coefficient of variation (CoV) analysis. RESULTS In simulations, all models had high R2* accuracy (error <5%) and precision (CoV <10%) for all SNRs, shorter ΔTE (≤0.5 msec), and longer TEmax (≥10.1 msec); except the constant offset model overestimated R2* at the lowest SNR. In phantoms and in vivo, all models produced similar R2* values for different SNRs and shorter ΔTEs (slopes: 0.99-1.06, R2 > 0.99, P < 0.001). In all experiments, R2* results degraded for high R2* values with longer ΔTE (≥1 msec). In vivo, shorter and longer TEmax gave similar R2* results (slopes: 1.02-1.06, R2 > 0.99, P < 0.001) for the noise subtraction model for 25≤R2*≤2000 s-1 . However, both quadratic and constant offset models, using shorter TEmax (≤4.7 msec) overestimated R2* and yielded high CoVs up to ∼170% for low R2* (<250 s-1 ). DATA CONCLUSION UTE with TEmax ≥ 10.1 msec and ΔTE ≤ 0.5 msec yields accurate R2* estimates over the entire clinical HIC range. Monoexponential fitting with noise subtraction is the most robust signal model to changes in UTE parameters and achieves the highest R2* accuracy and precision. LEVEL OF EVIDENCE 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1475-1488.
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Affiliation(s)
- Aaryani Tipirneni-Sajja
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.,Department of Biomedical Engineering, The University of Memphis, Memphis, Tennessee, USA
| | - Ralf B Loeffler
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Axel J Krafft
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.,Department of Radiology, Medical Physics, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andrea N Sajewski
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Robert J Ogg
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Jane S Hankins
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Claudia M Hillenbrand
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
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Ma YJ, Carl M, Searleman A, Lu X, Chang EY, Du J. 3D adiabatic T 1ρ prepared ultrashort echo time cones sequence for whole knee imaging. Magn Reson Med 2018; 80:1429-1439. [PMID: 29493004 PMCID: PMC6097905 DOI: 10.1002/mrm.27131] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 01/22/2018] [Accepted: 01/23/2018] [Indexed: 12/29/2022]
Abstract
PURPOSE To develop a 3D adiabatic T1ρ prepared ultrashort echo time cones (3D AdiabT1ρ UTE-Cones) sequence for whole knee imaging on a clinical 3T scanner. METHODS A train of adiabatic full passage pulses were used for spin locking, followed by time-efficient multispoke UTE acquisition to detect signals from both short and long T2 tissues in the whole knee joint. A modified signal model was proposed for multispoke UTE data fitting. The feasibility of this 3D AdiabT1ρ UTE-Cones technique was demonstrated through numerical simulation, phantom, and ex vivo knee sample studies. The 3D AdiabT1ρ UTE-Cones technique was then applied to 6 in vivo knee joints of healthy volunteers to measure T1ρ values of quadriceps tendon, patellar tendon, anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), meniscus, patellar cartilage, and muscle. RESULTS Numerical simulation, phantom and ex vivo knee sample studies demonstrated the feasibility of whole knee imaging using the proposed multispoke 3D AdiabT1ρ UTE-Cones sequence. The healthy volunteer knee study demonstrated an averaged T1ρ of 13.9 ± 0.7 ms for the quadriceps tendon, 9.7 ± 0.8 ms for the patellar tendon, 34.9 ± 2.8 ms for the ACL, 21.6 ± 1.4 ms for the PCL, 22.5 ± 1.9 ms for the meniscus, 44.5 ± 2.4 ms for the patellar cartilage, and 43.2 ± 1.1 ms for the muscle. CONCLUSION The 3D AdiabT1ρ UTE-Cones sequence allows volumetric T1ρ assessment of both short and long T2 tissues in the knee joint on a clinical 3T scanner.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, CA
| | | | - Adam Searleman
- Department of Radiology, University of California, San Diego, CA
| | - Xing Lu
- Department of Radiology, University of California, San Diego, CA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA
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Ma YJ, Lu X, Carl M, Zhu Y, Szeverenyi NM, Bydder GM, Chang EY, Du J. Accurate T 1 mapping of short T 2 tissues using a three-dimensional ultrashort echo time cones actual flip angle imaging-variable repetition time (3D UTE-Cones AFI-VTR) method. Magn Reson Med 2018; 80:598-608. [PMID: 29314235 PMCID: PMC5912804 DOI: 10.1002/mrm.27066] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 11/14/2017] [Accepted: 12/11/2017] [Indexed: 02/04/2023]
Abstract
PURPOSE To develop an accurate T1 measurement method for short T2 tissues using a combination of a 3-dimensional ultrashort echo time cones actual flip angle imaging technique and a variable repetition time technique (3D UTE-Cones AFI-VTR) on a clinical 3T scanner. METHODS First, the longitudinal magnetization mapping function of the excitation pulse was obtained with the 3D UTE-Cones AFI method, which provided information about excitation efficiency and B1 inhomogeneity. Then, the derived mapping function was substituted into the VTR fitting to generate accurate T1 maps. Numerical simulation and phantom studies were carried out to compare the AFI-VTR method with a B1 -uncorrected VTR method, a B1 -uncorrected variable flip angle (VFA) method, and a B1 -corrected VFA method. Finally, the 3D UTE-Cones AFI-VTR method was applied to bovine bone samples (N = 6) and healthy volunteers (N = 3) to quantify the T1 of cortical bone. RESULTS Numerical simulation and phantom studies showed that the 3D UTE-Cones AFI-VTR technique provides more accurate measurement of the T1 of short T2 tissues than the B1 -uncorrected VTR and VFA methods or the B1 -corrected VFA method. The proposed 3D UTE-Cones AFI-VTR method showed a mean T1 of 240 ± 25 ms for bovine cortical bone and 218 ± 10 ms for the tibial midshaft of human volunteers, respectively, at 3 T. CONCLUSION The 3D UTE-Cones AFI-VTR method can provide accurate T1 measurements of short T2 tissues such as cortical bone. Magn Reson Med 80:598-608, 2018. © 2018 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, CA
| | - Xing Lu
- Department of Radiology, University of California, San Diego, CA
| | | | - Yanchun Zhu
- Department of Radiology, University of California, San Diego, CA
| | | | - Graeme M Bydder
- Department of Radiology, University of California, San Diego, CA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA
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Ma YJ, Zhu Y, Lu X, Carl M, Chang EY, Du J. Short T 2 imaging using a 3D double adiabatic inversion recovery prepared ultrashort echo time cones (3D DIR-UTE-Cones) sequence. Magn Reson Med 2018; 79:2555-2563. [PMID: 28913879 PMCID: PMC5821562 DOI: 10.1002/mrm.26908] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 07/22/2017] [Accepted: 08/16/2017] [Indexed: 12/21/2022]
Abstract
PURPOSE To investigate high contrast imaging of short T2 tissues with a three-dimensional double adiabatic inversion recovery prepared ultrashort echo time Cones (3D DIR-UTE-Cones) sequence. METHODS The sequence used two sequential adiabatic inversion pulses to suppress signals from long T2 tissues, followed by multispoke UTE acquisition to detect signals from short T2 tissues. The two adiabatic inversion pulses are identical with a center frequency located at the water peak, but the spectral width is broad enough to cover both water and fat frequencies. The feasibility of this technique was demonstrated through numerical simulation and phantom studies. Finally, DIR-UTE-Cones was applied to three healthy volunteers to image cortical bone, patellar tendon, and Achilles tendon. T2* was also measured via single-component exponential fitting. RESULTS Numerical simulation suggests that the DIR technique provides perfect nulling of muscle and fat as well as efficient suppression of other long T2 tissues with T1 values between fat and water or those above water. Excellent image contrast can be achieved with DIR-UTE-Cones for the short T2 tissues, with fitted T2* values of 0.28-0.38 ms for cortical bone, 0.56 ± 0.07 ms for the patella tendon, and 0.45 ± 0.06 ms for the Achilles tendon, respectively. CONCLUSION The 3D DIR-UTE-Cones sequence provides robust suppression of long T2 tissues and allows selective imaging as well as T2* measurement of short T2 tissues such as cortical bone, patellar tendon, and the Achilles tendon. Magn Reson Med 79:2555-2563, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, CA
| | - Yanchun Zhu
- Department of Radiology, University of California, San Diego, CA
| | - Xing Lu
- Department of Radiology, University of California, San Diego, CA
| | | | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, CA
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Lu X, Ma Y, Chang EY, He Q, Searleman A, von Drygalski A, Du J. Simultaneous quantitative susceptibility mapping (QSM) and R2* for high iron concentration quantification with 3D ultrashort echo time sequences: An echo dependence study. Magn Reson Med 2018; 79:2315-2322. [PMID: 29314215 DOI: 10.1002/mrm.27062] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 12/05/2017] [Accepted: 12/05/2017] [Indexed: 12/12/2022]
Abstract
PURPOSE To evaluate the echo dependence of 3D ultrashort echo time (TE) quantitative susceptibility mapping (3D UTE-QSM) and effective transverse relaxation rate ( R2*) measurement in the setting of high concentrations of iron oxide nanoparticles. METHODS A phantom study with iron concentrations ranging from 2 to 22 mM was performed using a 3D UTE Cones sequence. Simultaneous QSM processing with morphology-enabled dipole inversion (MEDI) and R2* single exponential fitting was conducted offline with the acquired 3D UTE data. The dependence of UTE-QSM and R2* on echo spacing (ΔTE) and first TE (TE1 ) was investigated. RESULTS A linear relationship was observed between UTE-QSM measurement and iron concentration up to 22 mM only, with the minimal TE1 of 0.032 ms and ΔTE of less than 0.1 ms. A linear relationship was observed between R2* and iron concentration up to 22 mM only when TE1 was less than 0.132 ms and ΔTE was less than 1.2 ms. UTE-QSM with MEDI processing showed strong dependence on ΔTE and TE1 , especially at high iron concentrations. CONCLUSION UTE-QSM is more sensitive than R2* measurement to TE selection. Both an ultrashort TE1 and a small ΔTE are needed to achieve accurate QSM for high iron concentrations. Magn Reson Med 79:2315-2322, 2018. © 2018 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Xing Lu
- Department of Radiology, University of California, San Diego, California, USA.,Institute of Electrical Engineering, Chinese Academy of Science, Beijing, China
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, California, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, California, USA.,Radiology Service, VA San Diego Healthcare System, San Diego, California, USA
| | - Qun He
- Department of Radiology, University of California, San Diego, California, USA
| | - Adam Searleman
- Department of Radiology, University of California, San Diego, California, USA
| | - Annette von Drygalski
- Department of Medicine, Division of Hematology/Oncology, University of California, San Diego, California, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, California, USA
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Ma YJ, Tadros A, Du J, Chang EY. Quantitative two-dimensional ultrashort echo time magnetization transfer (2D UTE-MT) imaging of cortical bone. Magn Reson Med 2017; 79:1941-1949. [PMID: 28776754 DOI: 10.1002/mrm.26846] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 06/28/2017] [Accepted: 06/30/2017] [Indexed: 01/19/2023]
Abstract
PURPOSE To investigate quantitative 2D ultrashort echo time magnetization transfer (UTE-MT) imaging in ex vivo bovine cortical bone and in vivo human tibial cortical bone. METHODS Data were acquired from five fresh bovine cortical bone samples and five healthy volunteer tibial cortical bones using a 2D UTE-MT sequence on a clinical 3T scanner. The 2D UTE-MT sequence used four or five MT powers with five frequency offsets. Results were analyzed with a two-pool quantitative MT model, providing measurements of macromolecular fraction (f), macromolecular proton transverse relaxation times (T2m ), proton exchange rates from water/macromolecular to the macromolecular/water pool (RM0m /RM0w ), and spin-lattice relaxation rate of water pool (R1w ). A sequential air-drying study for a small bovine cortical bone chip was used to investigate whether above MT modeling parameters were sensitive to the water loss. RESULTS Mean fresh bovine cortical bone values for f, T2m , R1w , RM0m , and RM0w were 59.9 ± 7.3%, 14.6 ± 0.3 μs, 9.9 ± 2.4 s-1 , 17.9 ± 3.6 s-1 , and 11.8 ± 2.0 s-1 , respectively. Mean in vivo human cortical bone values for f, T2m , R1w , RM0m and RM0w were 54.5 ± 4.9%, 15.4 ± 0.6 μs, 8.9 ± 1.1 s-1 , 11.5 ± 3.5 s-1 , and 9.5 ± 1.9 s-1 , respectively. The sequential air-drying study shows that f, RM0m , and R1w were increased with longer drying time. CONCLUSION UTE-MT two-pool modeling provides novel and useful quantitative information for cortical bone. Magn Reson Med 79:1941-1949, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, San Diego, California, USA
| | - Anthony Tadros
- Department of Radiology, University of California, San Diego, San Diego, California, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, San Diego, California, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, San Diego, California, USA.,Radiology Service, VA San Diego Healthcare System, San Diego, California, USA
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Abstract
OBJECTIVE The purposes of this article are to present a state-of-the-art routine protocol for MRI of the ankle, to provide problem-solving tools based on specific clinical indications, and to introduce principles for the implementation of ultrashort echo time MRI of the ankle, including morphologic and quantitative assessment. CONCLUSION Ankle injury is common among both athletes and the general population, and MRI is the established noninvasive means of evaluation. The design of an ankle protocol depends on various factors. Higher magnetic field improves signal-to-noise ratio but increases metal artifact. Specialized imaging planes are useful but prolong acquisition times. MR neurography is useful, but metal reduction techniques are needed whenever a metal prosthesis is present. An ultrashort echo time sequence is a valuable tool for both structural and quantitative evaluation.
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Ma YJ, Chang EY, Carl M, Du J. Quantitative magnetization transfer ultrashort echo time imaging using a time-efficient 3D multispoke Cones sequence. Magn Reson Med 2017; 79:692-700. [PMID: 28470838 DOI: 10.1002/mrm.26716] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 02/19/2017] [Accepted: 03/23/2017] [Indexed: 12/21/2022]
Abstract
PURPOSE To accelerate the quantitative ultrashort echo time imaging using a time-efficient 3D multispoke Cones sequence with magnetization transfer (3D UTE-Cones-MT) and signal modeling. THEORY AND METHODS A 3D UTE-Cones-MT acquisition scheme with multispoke per MT preparation and a modified rectangular pulse (RP) approximation was developed for two-pool MT modeling of macromolecular and water components including their relative fractions, relaxation times and exchange rates. Numerical simulation and cadaveric specimens, including human Achilles tendon and bovine cortical bone, were investigated using a clinical 3T scanner. RESULTS Numerical simulation showed that the modified RP model provided accurate estimation of MT parameters when multispokes were acquired per MT preparation. For the experiment with the Achilles tendon and cortical bone samples, the macromolecular fractions were 20.4 ± 2.0% and 59.4 ± 5.3%, respectively. CONCLUSION The 3D multispoke UTE-Cones-MT sequence can be used for fast volumetric assessment of macromolecular and water components in short T2 tissues. Magn Reson Med 79:692-700, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, California, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, California, USA.,Radiology Service, VA San Diego Healthcare System, San Diego, California, USA
| | | | - Jiang Du
- Department of Radiology, University of California, San Diego, California, USA
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Kijowski R, Wilson JJ, Liu F. Bicomponent ultrashort echo time T2* analysis for assessment of patients with patellar tendinopathy. J Magn Reson Imaging 2017; 46:1441-1447. [PMID: 28263448 DOI: 10.1002/jmri.25689] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 02/10/2017] [Indexed: 12/20/2022] Open
Abstract
PURPOSE To compare bicomponent ultrashort echo time (UTE) T2* parameters of patellar tendon between healthy volunteers and patients with patellar tendinopathy. MATERIALS AND METHODS This study was performed with Institutional Review Board approval and with all subjects signing informed consent. A UTE- T2* mapping sequence was performed at 3.0T on the knees of 10 healthy volunteers and in 11 patients with patellar tendinopathy. The UTE- T2* relaxation times of the fast relaxing macromolecular bound water component ( T2*F) and the slow relaxing bulk water component ( T2*S) and the fraction of the fast relaxing macromolecular bound water component (FF ) of patellar tendon were measured in all subjects. Wilcoxon rank-sum tests were used to compare UTE- T2* parameters between healthy volunteers and patients with patellar tendinopathy. RESULTS Mean T2*F, T2*S, and FF of the patellar tendon was 1.5 msec, 23.1 msec, and 79.5%, respectively, for healthy volunteers and 1.9 msec, 22.3 msec, and 75.5%, respectively, for patients with patellar tendinopathy. There were statistically significant differences between groups of subjects for T2*F (P = 0.01) and FF (P = 0.007) but not T2*S (P = 0.10) of the patellar tendon. CONCLUSION Patients with patellar tendinopathy had significantly higher T2*F and significantly lower FF of patellar tendon than healthy volunteers, which suggests that bicomponent UTE- T2* parameters can detect changes in the composition and microstructure of degenerative tendon. LEVEL OF EVIDENCE 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1441-1447.
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Affiliation(s)
- Richard Kijowski
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - John J Wilson
- Department of Orthopedics and Rehabilitation, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Fang Liu
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
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Higano NS, Fleck RJ, Spielberg DR, Walkup LL, Hahn AD, Thomen RP, Merhar SL, Kingma PS, Tkach JA, Fain SB, Woods JC. Quantification of neonatal lung parenchymal density via ultrashort echo time MRI with comparison to CT. J Magn Reson Imaging 2017; 46:992-1000. [PMID: 28160357 DOI: 10.1002/jmri.25643] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 01/06/2017] [Indexed: 01/12/2023] Open
Abstract
PURPOSE To demonstrate that ultrashort echo time (UTE) magnetic resonance imaging (MRI) can achieve computed tomography (CT)-like quantification of lung parenchyma in free-breathing, non-sedated neonates. Because infant CTs are used sparingly, parenchymal disease evaluation via UTE MRI has potential for translational impact. MATERIALS AND METHODS Two neonatal control cohorts without suspected pulmonary morbidities underwent either a research UTE MRI (n = 5; 1.5T) or a clinically-ordered CT (n = 9). Whole-lung means and anterior-posterior gradients of UTE-measured image intensity (arbitrary units, au, normalized to muscle) and CT-measured density (g/cm3 ) were compared (Mann-Whitney U-test). Separately, a diseased neonatal cohort (n = 5) with various pulmonary morbidities underwent both UTE MRI and CT. UTE intensity and CT density were compared with Spearman correlations within ∼33 anatomically matched regions of interest (ROIs) in each diseased subject, spanning low- to high-density tissues. Radiological classifications were evaluated in all ROIs, with mean UTE intensities and CT densities compared in each classification. RESULTS In control subjects, whole-lung UTE intensities (0.51 ± 0.04 au) were similar to CT densities (0.44 ± 0.09 g/cm3 ) (P = 0.062), as were UTE (0.021 ± 0.020 au/cm) and CT (0.034 ± 0.024 [g/cm3 ]/cm) anterior-posterior gradients (P = 0.351). In diseased subjects' ROIs, significant correlations were observed between UTE and CT (P ≤0.007 in each case). Relative differences between UTE and CT were small in all classifications (4-25%). CONCLUSION These results demonstrate a strong association between UTE image intensity and CT density, both between whole-lung tissue in control patients and regional radiological pathologies in diseased patients. This indicates the potential for UTE MRI to longitudinally evaluate neonatal pulmonary disease and to provide visualization of pathologies similar to CT, without sedation/anesthesia or ionizing radiation. LEVEL OF EVIDENCE 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:992-1000.
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Affiliation(s)
- Nara S Higano
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Physics, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Robert J Fleck
- Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - David R Spielberg
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Laura L Walkup
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Andrew D Hahn
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Robert P Thomen
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Stephanie L Merhar
- Division of Neonatology and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Paul S Kingma
- Division of Neonatology and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Jean A Tkach
- Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Sean B Fain
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Jason C Woods
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Physics, Washington University in St. Louis, St. Louis, Missouri, USA.,Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
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45
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Manhard MK, Harkins KD, Gochberg DF, Nyman JS, Does MD. 30-Second bound and pore water concentration mapping of cortical bone using 2D UTE with optimized half-pulses. Magn Reson Med 2017; 77:945-950. [PMID: 28090655 DOI: 10.1002/mrm.26605] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Revised: 11/18/2016] [Accepted: 12/21/2016] [Indexed: 11/09/2022]
Abstract
PURPOSE MRI of cortical bone has the potential to offer new information about fracture risk. Current methods are typically performed with 3D acquisitions, which suffer from long scan times and are generally limited to extremities. This work proposes using 2D UTE with half pulses for quantitatively mapping bound and pore water in cortical bone. METHODS Half-pulse 2D UTE methods were implemented on a 3T Philips Achieva scanner using an optimized slice-select gradient waveform, with preparation pulses to selectively image bound or pore water. The 2D methods were quantitatively compared with previously implemented 3D methods in the tibia in five volunteers. RESULTS The mean difference between bound and pore water concentration acquired from 3D and 2D sequences was 0.6 and 0.9 mol 1 H/Lbone (3 and 12%, respectively). While 2D pore water methods tended to slightly overestimate concentrations relative to 3D methods, differences were less than scan-rescan uncertainty and expected differences between healthy and fracture-prone bones. CONCLUSION Quantitative bound and pore water concentration mapping in cortical bone can be accelerated by 2 orders of magnitude using 2D protocols with optimized half-pulse excitation. Magn Reson Med 77:945-950, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Mary Kate Manhard
- Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt University Institute of Imaging Science, Nashville, Tennessee, USA
| | - Kevin D Harkins
- Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt University Institute of Imaging Science, Nashville, Tennessee, USA
| | - Daniel F Gochberg
- Vanderbilt University Institute of Imaging Science, Nashville, Tennessee, USA.,Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee, USA.,Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee, USA
| | - Jeffry S Nyman
- Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt University Institute of Imaging Science, Nashville, Tennessee, USA.,Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, Tennessee, USA.,Orthopaedic Surgery and Rehabilitation, Vanderbilt University, Nashville, Tennessee, USA.,Center for Bone Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Mark D Does
- Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt University Institute of Imaging Science, Nashville, Tennessee, USA.,Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee, USA.,Electrical Engineering, Vanderbilt University, Nashville, Tennessee, USA
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46
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Ma YJ, Shao H, Du J, Chang EY. Ultrashort echo time magnetization transfer (UTE-MT) imaging and modeling: magic angle independent biomarkers of tissue properties. NMR Biomed 2016; 29:1546-1552. [PMID: 27599046 PMCID: PMC5069073 DOI: 10.1002/nbm.3609] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Revised: 07/09/2016] [Accepted: 07/26/2016] [Indexed: 05/24/2023]
Abstract
MRI biomarkers such as T2 , T2 * and T1rho have been widely used, but are confounded by the magic angle effect. The purpose of this study is to investigate the use of the two-dimensional ultrashort echo time magnetization transfer (UTE-MT) sequence for potential magic angle independent MR biomarkers. Magnetization transfer was investigated in cadaveric Achilles tendon samples using the UTE-MT sequence at five MT powers and five frequency offsets ranging from 2 to 50 kHz. The protocol was applied at five sample orientations ranging from 0 to 90° relative to the B0 field. The results were analyzed with a two-pool quantitative MT model. Multiple TE data were also acquired and mono-exponential T2 * was calculated for each orientation. Macromolecular proton fractions and exchange rates derived from UTE-MT modeling did not appreciably change between the various orientations, whereas the T2 * relaxation time demonstrated up to a sixfold increase from 0° to 55°. The UTE-MT technique with two-pool modeling shows promise as a clinically compatible technique that is resistant to the magic angle effect. This method provides information on the macromolecular proton pool that cannot be directly obtained by other methods, including regular UTE techniques.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California, San Diego, California, USA
| | - Hongda Shao
- Department of Radiology, University of California, San Diego, California, USA
| | - Jiang Du
- Department of Radiology, University of California, San Diego, California, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, California, USA.
- Radiology Service, VA San Diego Healthcare System, San Diego, California, USA.
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47
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Sheikh K, Guo F, Capaldi DPI, Ouriadov A, Eddy RL, Svenningsen S, Parraga G. Ultrashort echo time MRI biomarkers of asthma. J Magn Reson Imaging 2016; 45:1204-1215. [PMID: 27731948 DOI: 10.1002/jmri.25503] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 09/20/2016] [Indexed: 01/08/2023] Open
Abstract
PURPOSE To develop and assess ultrashort echo-time (UTE) magnetic resonance imaging (MRI) biomarkers of lung function in asthma patients. MATERIALS AND METHODS Thirty participants including 13 healthy volunteers and 17 asthmatics provided written informed consent to UTE and pulmonary function tests in addition to hyperpolarized-noble-gas 3T MRI and computed tomography (CT) for asthmatics only. The difference in MRI signal-intensity (SI) across four lung volumes (full-expiration, functional-residual-capacity [FRC], FRC+1L, and full-inspiration) was determined on a voxel-by-voxel basis to generate dynamic proton-density (DPD) maps. MRI ventilation-defect-percent (VDP), UTE SI, and DPD values as well as CT radiodensity were determined for whole lung and individual lobes. RESULTS Mean SI at full-expiration (P < 0.01), FRC (P < 0.05), and DPD (P < 0.01) were greater in healthy volunteers compared to asthmatics. In asthmatics, UTE SI at full-expiration and DPD were correlated with FEV1 /FVC (SI r = 0.73/P = 0.002; DPD r = 0.75/P = 0.003), RV/TLC (SI r = -0.57/P = 0.02), or RV (DPD r = -0.62/P = 0.02), CT radiodensity (SI r = 0.83/P = 0.006; DPD r = 0.71/P = 0.01), and lobar VDP (SI rs = -0.33/P = 0.02; DPD rs = -0.47/P = 0.01). CONCLUSION In patients with asthma, UTE SI and dynamic proton-density were related to pulmonary function measurements, whole lung and lobar VDP, as well as CT radiodensity. Thus, UTE MRI biomarkers may reflect ventilation heterogeneity and/or gas-trapping in asthmatics using conventional equipment, making this approach potentially amenable for clinical use. LEVEL OF EVIDENCE 2 J. Magn. Reson. Imaging 2017;45:1204-1215.
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Affiliation(s)
- Khadija Sheikh
- Robarts Research Institute, The University of Western Ontario, London, Canada.,Department of Medical Biophysics, The University of Western Ontario, London, Canada
| | - Fumin Guo
- Robarts Research Institute, The University of Western Ontario, London, Canada.,Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Canada
| | - Dante P I Capaldi
- Robarts Research Institute, The University of Western Ontario, London, Canada.,Department of Medical Biophysics, The University of Western Ontario, London, Canada
| | - Alexei Ouriadov
- Robarts Research Institute, The University of Western Ontario, London, Canada
| | - Rachel L Eddy
- Robarts Research Institute, The University of Western Ontario, London, Canada.,Department of Medical Biophysics, The University of Western Ontario, London, Canada
| | - Sarah Svenningsen
- Robarts Research Institute, The University of Western Ontario, London, Canada
| | - Grace Parraga
- Robarts Research Institute, The University of Western Ontario, London, Canada.,Department of Medical Biophysics, The University of Western Ontario, London, Canada.,Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Canada
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48
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Johnson EM, Vyas U, Ghanouni P, Pauly KB, Pauly JM. Improved cortical bone specificity in UTE MR Imaging. Magn Reson Med 2016; 77:684-695. [PMID: 26972442 DOI: 10.1002/mrm.26160] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 12/20/2015] [Accepted: 01/18/2016] [Indexed: 12/21/2022]
Abstract
PURPOSE Methods for direct visualization of compact bone using MRI have application in several "MR-informed" technologies, such as MR-guided focused ultrasound, MR-PET reconstruction and MR-guided radiation therapy. The specificity of bone imaging can be improved by manipulating image sensitivity to Bloch relaxation phenomena, facilitating distinction of bone from other tissues detected by MRI. METHODS From Bloch equation dynamics, excitation pulses suitable for creating specific sensitivity to short-T2 magnetization from cortical bone are identified. These pulses are used with UTE subtraction demonstrate feasibility of MR imaging of compact bone with positive contrast. RESULTS MR images of bone structures are acquired with contrast similar to that observed in x-ray CT images. Through comparison of MR signal intensities with CT Hounsfield units of the skull, the similarity of contrast is quantified. The MR technique is also demonstrated in other regions of the body that are relevant for interventional procedures, such as the shoulder, pelvis and leg. CONCLUSION Matching RF excitation pulses to relaxation rates improves the specificity to bone of short-T2 contrast. It is demonstrated with a UTE sequence to acquire images of cortical bone with positive contrast, and the contrast is verified by comparison with x-ray CT. Magn Reson Med 77:684-695, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Ethan M Johnson
- Magnetic Resonance Systems Research Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - Urvi Vyas
- Magnetic Resonance Systems Research Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - Pejman Ghanouni
- Magnetic Resonance Systems Research Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - Kim Butts Pauly
- Magnetic Resonance Systems Research Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - John M Pauly
- Magnetic Resonance Systems Research Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California, USA
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49
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Higano NS, Hahn AD, Tkach JA, Cao X, Walkup LL, Thomen RP, Merhar SL, Kingma PS, Fain SB, Woods JC. Retrospective respiratory self-gating and removal of bulk motion in pulmonary UTE MRI of neonates and adults. Magn Reson Med 2016; 77:1284-1295. [PMID: 26972576 DOI: 10.1002/mrm.26212] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/09/2016] [Accepted: 02/20/2016] [Indexed: 12/30/2022]
Abstract
PURPOSE To implement pulmonary three-dimensional (3D) radial ultrashort echo-time (UTE) MRI in non-sedated, free-breathing neonates and adults with retrospective motion tracking of respiratory and intermittent bulk motion, to obtain diagnostic-quality, respiratory-gated images. METHODS Pulmonary 3D radial UTE MRI was performed at 1.5 tesla (T) during free breathing in neonates and adult volunteers for validation. Motion-tracking waveforms were obtained from the time course of each free induction decay's initial point (i.e., k-space center), allowing for respiratory-gated image reconstructions that excluded data acquired during bulk motion. Tidal volumes were calculated from end-expiration and end-inspiration images. Respiratory rates were calculated from the Fourier transform of the motion-tracking waveform during quiet breathing, with comparison to physiologic prediction in neonates and validation with spirometry in adults. RESULTS High-quality respiratory-gated anatomic images were obtained at inspiration and expiration, with less respiratory blurring at the expense of signal-to-noise for narrower gating windows. Inspiration-expiration volume differences agreed with physiologic predictions (neonates; Bland-Altman bias = 6.2 mL) and spirometric values (adults; bias = 0.11 L). MRI-measured respiratory rates compared well with the observed rates (biases = -0.5 and 0.2 breaths/min for neonates and adults, respectively). CONCLUSIONS Three-dimensional radial pulmonary UTE MRI allows for retrospective respiratory self-gating and removal of intermittent bulk motion in free-breathing, non-sedated neonates and adults. Magn Reson Med 77:1284-1295, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Nara S Higano
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Physics, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Andrew D Hahn
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Jean A Tkach
- Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Xuefeng Cao
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Physics, University of Cincinnati, Cincinnati, Ohio, USA
| | - Laura L Walkup
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Robert P Thomen
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Physics, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Stephanie L Merhar
- Division of Neonatology and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Paul S Kingma
- Division of Neonatology and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Sean B Fain
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Jason C Woods
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Physics, Washington University in St. Louis, St. Louis, Missouri, USA.,Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
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50
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Li C, Magland JF, Zhao X, Seifert AC, Wehrli FW. Selective in vivo bone imaging with long-T 2 suppressed PETRA MRI. Magn Reson Med 2016; 77:989-997. [PMID: 26914767 DOI: 10.1002/mrm.26178] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 02/01/2016] [Accepted: 02/01/2016] [Indexed: 12/22/2022]
Abstract
PURPOSE To design and evaluate an optimized PETRA (point-wise encoding time reduction with radial acquisition) sequence with long-T2 suppression at 3 Tesla. METHODS An adiabatic inversion recovery-based scheme was used to null the long-T2 signal. To minimize scan time, the signal was sampled multiple times after each inversion with variable excitation flip angles designed to yield constant short-T2 signal amplitude. The excitation pulses were phase-modulated, allowing for increased flip angle and higher signal-to-noise ratio (SNR). A fast, noniterative image reconstruction algorithm was designed to minimize image artifacts due to nonuniform excitation profile. RESULTS Phase-modulated pulse excitation, along with the noniterative reconstruction algorithm, allows the use of larger radiofrequency pulse flip angles, resulting in effective suppression of long-T2 protons and improved image SNR without causing image artifacts. Midtibia images representative of collagen-bound water yielded SNR of 15 at 1-mm isotropic resolution in 6.5 minutes with a standard extremity coil. Further, the technology is shown to be suited for generating multi-angle projection images of bone akin to X-ray images displaying subtle anatomic detail. CONCLUSION Optimized long-T2 suppressed PETRA allows imaging of bone matrix water unencumbered by long-T2 soft tissue and pore water protons, opening up new possibilities for anatomic bone imaging at isotropic resolution and quantification in clinically practical scan times. Magn Reson Med 77:989-997, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Cheng Li
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jeremy F Magland
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Xia Zhao
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Alan C Seifert
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Felix W Wehrli
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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