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Zhang Y, Deng C, Xia W, Ran J, Li X. Quantitative evaluation of knee cartilage in professional martial arts athletes using T2 mapping: a comparative study. J Athl Train 2024:498729. [PMID: 38291773 DOI: 10.4085/1062-6050-0127.23] [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] [Indexed: 02/01/2024]
Abstract
CONTEXT While the relationship between high-impact sports like football and basketball and the development of knee osteoarthritis is well established, the impact of martial arts on the knee joint remains unclear. OBJECTIVE To compare the imaging abnormalities of knee joints and T2 relaxation times of cartilage in professional martial arts athletes and healthy controls. DESIGN Cross-Sectional Study. SETTING Hospital imaging center. PATIENTS OR OTHER PARTICIPANTS Nine asymptomatic professional martial arts athletes and eighteen healthy volunteers. MAIN OUTCOMES MEASURE(S) 3T magnetic resonance imaging (MRI) of the knee was performed on the bilateral legs of athletes and the dominant leg of controls. The MRI protocol included conventional sequences used for morphological assessment (cartilage, meniscus, ligaments, joint effusion, and bone marrow edema) and T2 mapping used for quantitatively evaluating the cartilage. Knee cartilage was manually divided into eight regions, and T2 relaxation times of the corresponding subregions were measured. Fisher's exact test and t-test were utilized to compare the frequency of lesions and cartilage T2 values both among groups and between the athletes' limbs. P<0.05 was considered significant. RESULTS Professional martial arts athletes exhibited significantly higher frequencies of cartilage (55.6% vs. 11.1%, P=0.023) and ligament lesions (66.7% vs. 16.7%, P=0.026) compared to control group. Athletes showed higher T2 values in three distinct cartilage segments: the central weightbearing of medial femoral condyle (P=0.006), medial tibial plateau (P=0.012), and trochlea (P=0.032) when compared to the controls. Additionally, the dominant leg of athletes showed significantly higher T2 values compared to their non-dominant legs. CONCLUSIONS The findings demonstrated the impact of martial arts on the knee joint, characterized by higher prevalence of lesions and elevated cartilage T2 values, particularly in the medial compartment. The dominant legs of martial arts athletes seem to have higher risk of cartilage degeneration due to the observed interlimb differences in T2 values.
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Affiliation(s)
- Yao Zhang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Chenghu Deng
- Department of Physical Education, Wuhan University of Technology, Wuhan, 430070, China
| | - Wei Xia
- Department of Radiology, Wuhan Children's Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430015, China
| | - Jun Ran
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xiaoming Li
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
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Foltz MH, Johnson CP, Truong W, Polly DW, Ellingson AM. Morphological alterations of lumbar intervertebral discs in patients with adolescent idiopathic scoliosis. Spine J 2024; 24:172-184. [PMID: 37611875 PMCID: PMC10843277 DOI: 10.1016/j.spinee.2023.08.012] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 07/26/2023] [Accepted: 08/13/2023] [Indexed: 08/25/2023]
Abstract
BACKGROUND CONTEXT Etiology of adolescent idiopathic scoliosis (AIS) is still unknown. Prior in vitro research suggests intervertebral disc pathomorphology as a cause for the initiation and progression of the spinal deformity, however, this has not been well characterized in vivo. PURPOSE To quantify and compare lumbar disc health and morphology in AIS to controls. STUDY DESIGN/SETTING Cross-sectional study. METHODS All lumbar discs were imaged using a 3T MRI scanner. T2-weighted and quantitative T2* maps were acquired. Axial slices of each disc were reconstructed, and customized scripts were used to extract outcome measurements: Nucleus pulposus (NP) signal intensity and location, disc signal volume, transition zone slope, and asymmetry index. Pearson's correlation analysis was performed between the NP location and disc wedge angle for AIS patients. ANOVAs were utilized to elucidate differences in disc health and morphology metrics between AIS patients and healthy controls. α=0.05. RESULTS There were no significant differences in disc health metrics between controls and scoliotic discs. There was a significant shift in the NP location towards the convex side of the disc in AIS patients compared to healthy controls, with an associated increase of the transition zone slope on the convex side. Additionally, with increasing disc wedge angle, the NP center migrated towards the convex side of the disc. CONCLUSIONS The present study elucidates morphological distinctions of intervertebral discs between healthy adolescents and those diagnosed with AIS. Discs in patients diagnosed with AIS are asymmetric, with the NP shifted towards the convex side, which was exacerbated by an increased disc wedge angle. CLINICAL SIGNIFICANCE Investigation of the MRI signal distribution (T2w and T2* maps) within the disc suggests an asymmetric pressure gradient shifting the NP laterally towards the convexity. Quantifying the progression of these morphological alterations during maturation and in response to treatment will provide further insight into the mechanisms of curve progression and correction, respectively.
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Affiliation(s)
- Mary H Foltz
- Division of Rehabilitation Science, Department of Rehabilitation Medicine, University of Minnesota
| | - Casey P Johnson
- Department of Veterinary Clinical Sciences, University of Minnesota; Center for Magnetic Resonance Research, University of Minnesota
| | - Walter Truong
- Gillette Children's Specialty Healthcare; Department of Orthopedic Surgery, University of Minnesota
| | - David W Polly
- Department of Orthopedic Surgery, University of Minnesota
| | - Arin M Ellingson
- Division of Rehabilitation Science, Department of Rehabilitation Medicine, University of Minnesota; Department of Orthopedic Surgery, University of Minnesota; Division of Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota.
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Zhang Y, Wang X, Ye M, Li Z, Zhuang Y, Yang Q, Fu Q, Chen R, Gao E, Ren Y, Zhang Y, Cai S, Chen Z, Cai C, Dong Y, Bao J, Cheng J. Anti-motion Ultrafast T 2 Mapping Technique for Quantitative Detection of the Normal-Appearing Corticospinal Tract Changes in Subacute-Chronic Stroke Patients with Distal Lesions. Acad Radiol 2023:S1076-6332(23)00671-2. [PMID: 38142175 DOI: 10.1016/j.acra.2023.11.036] [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: 10/02/2023] [Revised: 11/17/2023] [Accepted: 11/22/2023] [Indexed: 12/25/2023]
Abstract
RATIONALE AND OBJECTIVES Stroke patients commonly face challenges during magnetic resonance imaging (MRI) examinations due to involuntary movements. This study aims to overcome these challenges by utilizing multiple overlapping-echo detachment (MOLED) quantitative technology. Through this technology, we also seek to detect microstructural changes of the normal-appearing corticospinal tract (NA-CST) in subacute-chronic stroke patients. MATERIALS AND METHODS 79 patients underwent 3.0 T MRI scans, including routine scans and MOLED technique. A deep learning network was utilized for image reconstruction, and the accuracy, reliability, and resistance to motion of the MOLED technique were validated on phantoms and volunteers. Subsequently, we assessed motor dysfunction severity, ischemic lesion volume, T2 values of the bilateral NA-CST, and the T2 ratio (rT2) between the ipsilesional and contralesional NA-CST in patients. RESULTS The MOLED technique showed high accuracy (P < 0.001) and excellent repeatability, with a mean coefficient of variation (CoV) of 1.11%. It provided reliable quantitative results even under head movement, with a mean difference (Meandiff)= 0.28% and a standard deviation difference (SDdiff)= 1.34%. Additionally, the T2 value of the ipsilesional NA-CST was significantly higher than contralesional side (P < 0.001), and a positive correlation was observed between rT2 and the severity of motor dysfunction (rs =0.575, P < 0.001). Furthermore, rT2 successfully predicted post-stroke motor impairment, with an area under the curve (AUC) was 0.883. CONCLUSION The MOLED technique offers significant advantages for quantitatively imaging stroke patients with involuntary movements. Additionally, T2 mapping from MOLED can detect microstructural changes in the NA-CST, potentially aiding in monitoring stroke-induced motor impairment.
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Affiliation(s)
- Yue Zhang
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Xiao Wang
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Ming Ye
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance Research, Xiamen University, Xiamen, 361000, China (M.Y., Q.Y., S.C., Z.C., C.C.)
| | - Zongye Li
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Yuchuan Zhuang
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, 14627, USA (Y.Z.)
| | - Qinqin Yang
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance Research, Xiamen University, Xiamen, 361000, China (M.Y., Q.Y., S.C., Z.C., C.C.)
| | - Qichang Fu
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Rui Chen
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Eryuan Gao
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Yanan Ren
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Yong Zhang
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Shuhui Cai
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance Research, Xiamen University, Xiamen, 361000, China (M.Y., Q.Y., S.C., Z.C., C.C.)
| | - Zhong Chen
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance Research, Xiamen University, Xiamen, 361000, China (M.Y., Q.Y., S.C., Z.C., C.C.)
| | - Congbo Cai
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance Research, Xiamen University, Xiamen, 361000, China (M.Y., Q.Y., S.C., Z.C., C.C.)
| | - Yanbo Dong
- Institute of Psychology, The Herzen State Pedagogical University of Russia, Saint Petersburg, 190121, Russia (Y.D.)
| | - Jianfeng Bao
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.)
| | - Jingliang Cheng
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, 450000, China (Y.Z., X.W., Z.L., Q.F., R.C., E.G., Y.R., Y.Z., J.B., J.C.).
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Bakermans AJ, Kouwenhoven M, de Vos J, de Vries DK, Reckman YJ, Farag ES, Koolbergen DR, Kluin J, Nederveen AJ, Strijkers GJ, Boekholdt SM. A comparison of myocardial magnetic resonance extracellular volume mapping at 3 T against histology of tissue collagen in severe aortic valve stenosis and obstructive hypertrophic cardiomyopathy. MAGMA 2023; 36:701-709. [PMID: 36820958 PMCID: PMC10504177 DOI: 10.1007/s10334-023-01070-6] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/10/2023] [Accepted: 02/10/2023] [Indexed: 02/24/2023]
Abstract
OBJECTIVE Quantitative extracellular volume fraction (ECV) mapping with MRI is commonly used to investigate in vivo diffuse myocardial fibrosis. This study aimed to validate ECV measurements against ex vivo histology of myocardial tissue samples from patients with aortic valve stenosis or hypertrophic cardiomyopathy. MATERIALS AND METHODS Sixteen patients underwent MRI examination at 3 T to acquire native T1 maps and post-contrast T1 maps after gadobutrol administration, from which hematocrit-corrected ECV maps were estimated. Intra-operatively obtained myocardial tissue samples from the same patients were stained with picrosirius red for quantitative histology of myocardial interstitial fibrosis. Correlations between in vivo ECV and ex vivo myocardial collagen content were evaluated with regression analyses. RESULTS Septal ECV was 30.3% ± 4.6% and correlated strongly (n = 16, r = 0.70; p = 0.003) with myocardial collagen content. Myocardial native T1 values (1206 ± 36 ms) did not correlate with septal ECV (r = 0.41; p = 0.111) or with myocardial collagen content (r = 0.32; p = 0.227). DISCUSSION We compared myocardial ECV mapping at 3 T against ex vivo histology of myocardial collagen content, adding evidence to the notion that ECV mapping is a surrogate marker for in vivo diffuse myocardial fibrosis.
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Affiliation(s)
- Adrianus J Bakermans
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands.
| | - Merel Kouwenhoven
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
- Biomedical Engineering and Physics, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Judith de Vos
- Biomedical Engineering and Physics, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Dylan K de Vries
- Department of Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Yolan J Reckman
- Department of Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Emile S Farag
- Department of Cardiothoracic Surgery, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - David R Koolbergen
- Department of Cardiothoracic Surgery, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Jolanda Kluin
- Department of Cardiothoracic Surgery, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Aart J Nederveen
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Gustav J Strijkers
- Biomedical Engineering and Physics, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - S Matthijs Boekholdt
- Department of Cardiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
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Sunkara S, Radulović S, Lipovšek S, Birkl C, Eggenreich S, Birkl-Toeglhofer AM, Schinagl M, Funk D, Stöger-Pollach M, Haybaeck J, Goessler W, Ropele S, Leitinger G. Autolysis Affects the Iron Cargo of Ferritins in Neurons and Glial Cells at Different Rates in the Human Brain. Cell Mol Neurobiol 2023. [PMID: 36920627 DOI: 10.1007/s10571-023-01332-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 02/27/2023] [Indexed: 03/16/2023]
Abstract
Iron is known to accumulate in neurological disorders, so a careful balance of the iron concentration is essential for healthy brain functioning. An imbalance in iron homeostasis could arise due to the dysfunction of proteins involved in iron homeostasis. Here, we focus on ferritin-the primary iron storage protein of the brain. In this study, we aimed to improve a method to measure ferritin-bound iron in the human post-mortem brain, and to discern its distribution in particular cell types and brain regions. Though it is known that glial cells and neurons differ in their ferritin concentration, the change in the number and distribution of iron-filled ferritin cores between different cell types during autolysis has not been revealed yet. Here, we show the cellular and region-wide distribution of ferritin in the human brain using state-of-the-art analytical electron microscopy. We validated the concentration of iron-filled ferritin cores to the absolute iron concentration measured by quantitative MRI and inductively coupled plasma mass spectrometry. We show that ferritins lose iron from their cores with the progression of autolysis whereas the overall iron concentrations were unaffected. Although the highest concentration of ferritin was found in glial cells, as the total ferritin concentration increased in a patient, ferritin accumulated more in neurons than in glial cells. Summed up, our findings point out the unique behaviour of neurons in storing iron during autolysis and explain the differences between the absolute iron concentrations and iron-filled ferritin in a cell-type-dependent manner in the human brain. The rate of loss of the iron-filled ferritin cores during autolysis is higher in neurons than in glial cells.
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Peng F, Xu H, Song Y, Xu K, Li S, Cai X, Guo Y, Gong L. Longitudinal study of multi-parameter quantitative magnetic resonance imaging in Duchenne muscular dystrophy: hyperresponsiveness of gluteus maximus and detection of subclinical disease progression in functionally stable patients. J Neurol 2023; 270:1439-1451. [PMID: 36385201 DOI: 10.1007/s00415-022-11470-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [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: 09/07/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To describe the disease progression of Duchenne muscular dystrophy (DMD) in the pelvic and thigh muscles over 1-year using multiple-parameter quantitative magnetic resonance imaging (qMRI), and to determine the most responsive muscle and predict subclinical disease progression in functionally stable patients. METHODS Fifty-four DMD patients (mean age 8.9 ± 2.5, range 5-15 years) completed baseline and 1-year follow-up qMRI examinations/biomarkers [3-point Dixon/fat fraction (FF); T1 mapping/T1; T2 mapping/T2]. Meanwhile, clinical assessments [NorthStar ambulatory assessment (NSAA) score] and timed function tests were performed in DMD patients. Twenty-four healthy male controls (range 5-15 years) accomplished baseline qMRI examinations. Group differences were compared using the Wilcoxon test. The standardized response mean (SRM) was taken as the responsiveness to the disease progression index. RESULTS FF, T1, and T2 in all DMD age subgroups changed significantly over 1-year (P < 0.05). Even in functionally stable patients (NSAA score increased, unchanged, or decreased by 1-point) over 1-year, significant increases in FF and T2 and decreases in T1 were observed in gluteus maximus (GMa), gluteus medius, vastus lateralis, and adductor magnus (P < 0.05). Overall, the SRM of FF, T1, and T2 was all the highest in GMa, which were 1.25, - 0.92, and 0.93, respectively. CONCLUSIONS qMRI biomarkers are responsive to disease progression and can also detect subclinical disease progression in functionally stable DMD patients over 1-year. GMa is the most responsive to disease progression of all the muscles analyzed. TRIAL REGISTRATION Chinese Clinical Trial Registry ( http://www.chictr.org.cn/index.aspx ) ChiCTR1800018340, 09/12/2018, prospectively registered.
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Affiliation(s)
- Fei Peng
- Department of Medical Imaging Center, The Second Affiliated Hospital of Nanchang University, Minde Road No. 1, Nanchang, 330006, Jiangxi Province, China
- Department of Radiology, Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, 20# Section 3 South Renmin Road, Chengdu, 610041, Sichuan Province, China
| | - Huayan Xu
- Department of Radiology, Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, 20# Section 3 South Renmin Road, Chengdu, 610041, Sichuan Province, China
| | - Yu Song
- Department of Radiology, Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, 20# Section 3 South Renmin Road, Chengdu, 610041, Sichuan Province, China
| | - Ke Xu
- Department of Radiology, Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, 20# Section 3 South Renmin Road, Chengdu, 610041, Sichuan Province, China
| | - Shuhao Li
- Department of Medical Imaging Center, The Second Affiliated Hospital of Nanchang University, Minde Road No. 1, Nanchang, 330006, Jiangxi Province, China
| | - Xiaotang Cai
- Department of Pediatrics Neurology, West China Second University Hospital, Sichuan University, 20# Section 3 South Renmin Road, Chengdu, 610041, Sichuan Province, China.
| | - Yingkun Guo
- Department of Radiology, Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, 20# Section 3 South Renmin Road, Chengdu, 610041, Sichuan Province, China.
| | - Lianggeng Gong
- Department of Medical Imaging Center, The Second Affiliated Hospital of Nanchang University, Minde Road No. 1, Nanchang, 330006, Jiangxi Province, China.
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Takashima H, Yoshimoto M, Ogon I, Takebayashi T, Imamura R, Akatsuka Y, Yamashita T. T1rho, T2, and T2* relaxation time based on grading of intervertebral disc degeneration. Acta Radiol 2023; 64:1116-1121. [PMID: 35876305 DOI: 10.1177/02841851221113936] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Previous studies have explored the biochemical changes of disc degeneration and its relevance in low back pain using various quantitative magnetic resonance imaging (MRI) techniques. However, quantitative evaluation of intervertebral disc (IVD) with MRI such as T1rho, T2, and T2* have not been previously analyzed and compared directly in the same patients. PURPOSE To investigate T1rho, T2, and T2* of IVD degeneration in the same patients, reveal the correlation coefficients of these values, and evaluate which values are more sensitive to detect the degree of IVD degeneration. MATERIAL AND METHODS The participants were 55 patients who underwent MRI examinations which the investigator classified the degree of IVD degeneration according to the Pfirrmann classification. The T1rho, T2, and T2* values of IVD were analyzed for their classification and were compared. RESULTS T1rho, T2, and T2* values were 74.3 ± 7.1, 61.2 ± 6.7, and 46.5 ± 16.3 ms (grade II); 61.6 ± 11.8, 48.9 ± 8.2, and 34.1 ± 11.8 ms (grade III); 50.8 ± 10.8, 38.9 ± 9.8, and 25.4 ± 8.1 ms, (grade IV); 44.5 ± 13.3, 34.8 ± 9.5, and 11.2 ± 6.6 ms (grade V), respectively. Those values significantly decreased with increasing grades, but T1rho and T2 values for grades IV and V were not different. CONCLUSION The T1rho and T2 values were excellent for the evaluation of initial to moderate IVD degeneration with water and proteoglycan content. In contrast, the T2* value was suitable for detailed evaluation of progressive IVD, even with poor water content.
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Affiliation(s)
- Hiroyuki Takashima
- Division of Radiology and Nuclear Medicine, 13035Sapporo Medical University Hospital, Sapporo, Japan
- Department of Orthopedic Surgery, 13035Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Mitsunori Yoshimoto
- Department of Orthopedic Surgery, 13035Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Izaya Ogon
- Department of Orthopedic Surgery, 13035Sapporo Medical University School of Medicine, Sapporo, Japan
| | | | - Rui Imamura
- Division of Radiology and Nuclear Medicine, 13035Sapporo Medical University Hospital, Sapporo, Japan
| | - Yoshihiro Akatsuka
- Division of Radiology and Nuclear Medicine, 13035Sapporo Medical University Hospital, Sapporo, Japan
| | - Toshihiko Yamashita
- Department of Orthopedic Surgery, 13035Sapporo Medical University School of Medicine, Sapporo, Japan
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Mahalingam N, Trout AT, Zhang B, Castro-Rojas C, Miethke AG, Dillman JR. Longitudinal changes in quantitative magnetic resonance imaging metrics in children and young adults with autoimmune liver disease. Abdom Radiol (NY) 2023; 48:1933-1944. [PMID: 36799997 DOI: 10.1007/s00261-022-03733-9] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/25/2022] [Accepted: 10/26/2022] [Indexed: 02/18/2023]
Abstract
PURPOSE To assess longitudinal changes in quantitative MRI metrics in pediatric and young adult patients with autoimmune liver disease (AILD). METHODS This prospective, IRB-approved study included 20 children and young adults (median age = 15 years) with primary sclerosing cholangitis (PSC)/autoimmune sclerosing cholangitis (ASC) and 19 (median age = 17 years) with autoimmune hepatitis (AIH). At a field strength of 1.5-T, T2*-corrected T1 mapping (cT1), 3D fast spin-echo MRCP, and 2D gradient recalled echo MR elastography (MRE) were performed at baseline, one year, and two years. cT1 and quantitative MRCP were processed using LiverMultiScan and MRCP + , respectively (Perspectum Ltd, Oxford, UK). Linear mixed models were used to assess longitudinal changes in quantitative MRI metrics. Spearman rank-order correlation was used to assess relationships between changes in quantitative MRI metrics. RESULTS Changes in quantitative MRI metrics greater than established repeatability coefficients were measured in six (cT1) and five (MRE) patients with PSC/ASC as well as in six patients (cT1 and MRE) with AIH, although linear mixed models identified no significant changes for the subgroups as a whole. For PSC/ASC, there were positive correlations between change in liver stiffness and changes in bile duct strictures (ρ = 0.68; p = 0.005) and bile duct dilations (ρ = 0.70; p = 0.004) between baseline and Year 2. CONCLUSION On average, there were no significant changes in quantitative MRI metrics over a two-year period in children and young adults with AILD. However, worsening cholangiopathy was associated with increasing liver stiffness by MRE in patients with PSC/ASC.
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Affiliation(s)
- Neeraja Mahalingam
- Department of Radiology, Cincinnati Children's Hospital Medical Center, 250 Albert Sabin Way, Cincinnati, OH, 45229, USA.
| | - Andrew T Trout
- Department of Radiology, Cincinnati Children's Hospital Medical Center, 250 Albert Sabin Way, Cincinnati, OH, 45229, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Bin Zhang
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Cyd Castro-Rojas
- Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Alexander G Miethke
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Jonathan R Dillman
- Department of Radiology, Cincinnati Children's Hospital Medical Center, 250 Albert Sabin Way, Cincinnati, OH, 45229, USA
- Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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Coppock JA, Zimmer NE, Englander ZA, Danyluk ST, Kosinski AS, Spritzer CE, Goode AP, DeFrate LE. In vivo intervertebral disc mechanical deformation following a treadmill walking "stress test" is inversely related to T1rho relaxation time. Osteoarthritis Cartilage 2023; 31:126-133. [PMID: 36191831 PMCID: PMC10127291 DOI: 10.1016/j.joca.2022.09.008] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 09/12/2022] [Accepted: 09/24/2022] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To assess the in vivo relationship between the mechanical response of intervertebral discs (IVDs) to dynamic activity and IVD biochemical composition assessed via T1rho relaxation imaging. DESIGN Eighteen asymptomatic participants with no history of low back pain (LBP), injury, or surgery underwent magnetic resonance (MR) imaging of their lumbar spine prior to and immediately following a treadmill walking "stress test." Anatomic (SPACE, FLASH) MR images were obtained pre- and post-exercise and utilized to measure IVD mechanical deformation. Quantitative (T1rho) imaging was performed pre-exercise to reflect IVD composition. Pre-exercise anatomic images were also utilized to assess IVD degenerative status based on the modified Pfirrmann scale. To quantify mechanical response, 3D surface models of the L1-L2-L5-S1 IVDs were created from manual segmentations of pre- and post-exercise anatomic images and utilized to assess changes in IVD height. IVD strain (%) was defined as change in IVD height normalized to pre-activity height. Linear mixed models were used to assess the relationships between IVD mechanical deformation (strain), composition (T1rho relaxation time), and degenerative status (Pfirrmann grade). RESULTS Increased compressive IVD strain was associated with lower T1rho relaxation times in the nucleus pulposus (NP) of the disc (βT1rho=5.07,CI:[1.52,7.77],Rmarg2=0.52,p=0.005). Thus, an inverse relationship between IVD strain and NP T1rho relaxation time was observed. CONCLUSION The in vivo mechanical response of the IVD to the "stress test" was sensitive to differences in NP composition. The results of this study suggest that quantification of in vivo IVD mechanical function and composition may provide insight into IVD health.
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Affiliation(s)
- J A Coppock
- Department of Biomedical Engineering, Duke University, Durham, NC, USA; Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA
| | - N E Zimmer
- Department of Biomedical Engineering, Duke University, Durham, NC, USA; Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA
| | - Z A Englander
- Department of Biomedical Engineering, Duke University, Durham, NC, USA; Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA
| | - S T Danyluk
- Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA
| | - A S Kosinski
- Department of Biostatistics & Bioinformatics, Duke University, Durham, NC, USA; Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, USA
| | - C E Spritzer
- Department of Radiology, Duke University School of Medicine, Durham, NC, USA
| | - A P Goode
- Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA; Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, USA; Department of Population Health Sciences, Duke University, Durham, NC, USA
| | - L E DeFrate
- Department of Biomedical Engineering, Duke University, Durham, NC, USA; Department of Orthopedic Surgery, Duke University School of Medicine, Durham, NC, USA; Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA.
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10
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Zhong AY, Digma LA, Hussain T, Feng CH, Conlin CC, Tye K, Lui AJ, Andreassen MMS, Rodríguez-Soto AE, Karunamuni R, Kuperman J, Kane CJ, Rakow-Penner R, Hahn ME, Dale AM, Seibert TM. Automated Patient-level Prostate Cancer Detection with Quantitative Diffusion Magnetic Resonance Imaging. EUR UROL SUPPL 2023; 47:20-8. [PMID: 36601040 DOI: 10.1016/j.euros.2022.11.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/14/2022] [Indexed: 12/23/2022] Open
Abstract
Background Multiparametric magnetic resonance imaging (mpMRI) improves detection of clinically significant prostate cancer (csPCa), but the subjective Prostate Imaging Reporting and Data System (PI-RADS) system and quantitative apparent diffusion coefficient (ADC) are inconsistent. Restriction spectrum imaging (RSI) is an advanced diffusion-weighted MRI technique that yields a quantitative imaging biomarker for csPCa called the RSI restriction score (RSIrs). Objective To evaluate RSIrs for automated patient-level detection of csPCa. Design setting and participants We retrospectively studied all patients (n = 151) who underwent 3 T mpMRI and RSI (a 2-min sequence on a clinical scanner) for suspected prostate cancer at University of California San Diego during 2017-2019 and had prostate biopsy within 180 d of MRI. Intervention We calculated the maximum RSIrs and minimum ADC within the prostate, and obtained PI-RADS v2.1 from medical records. Outcome measurements and statistical analysis We compared the performance of RSIrs, ADC, and PI-RADS for the detection of csPCa (grade group ≥2) on the best available histopathology (biopsy or prostatectomy) using the area under the curve (AUC) with two-tailed α = 0.05. We also explored whether the combination of PI-RADS and RSIrs might be superior to PI-RADS alone and performed subset analyses within the peripheral and transition zones. Results and limitations AUC values for ADC, RSIrs, and PI-RADS were 0.48 (95% confidence interval: 0.39, 0.58), 0.78 (0.70, 0.85), and 0.77 (0.70, 0.84), respectively. RSIrs and PI-RADS were each superior to ADC for patient-level detection of csPCa (p < 0.0001). RSIrs alone was comparable with PI-RADS (p = 0.8). The combination of PI-RADS and RSIrs had an AUC of 0.85 (0.78, 0.91) and was superior to either PI-RADS or RSIrs alone (p < 0.05). Similar patterns were seen in the peripheral and transition zones. Conclusions RSIrs is a promising quantitative marker for patient-level csPCa detection, warranting a prospective study. Patient summary We evaluated a rapid, advanced prostate magnetic resonance imaging technique called restriction spectrum imaging to see whether it could give an automated score that predicted the presence of clinically significant prostate cancer. The automated score worked about as well as expert radiologists' interpretation. The combination of the radiologists' scores and automated score might be better than either alone.
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11
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Shu D, Chen F, Guo W, Ding J, Dai S. Acute changes in knee cartilage and meniscus following long-distance running in habituate runners: a systematic review on studies using quantitative magnetic resonance imaging. Skeletal Radiol 2022; 51:1333-1345. [PMID: 34854970 DOI: 10.1007/s00256-021-03943-0] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 10/13/2021] [Accepted: 10/13/2021] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Running is among the most popular recreational activities; nonetheless, the acute post-race changes of cartilage or meniscus have rarely been determined. The current study aimed to review the acute changes in knee cartilage and meniscus among habituate runners following long-distance running detected by using quantitative magnetic resonance imaging (MRI). MATERIALS AND METHODS Systematic literature search was performed on those dominate clinical databases which including MEDLINE, Cochrane, Embase, ScienceDirect, and Web of Science. Included studies should be conducted on healthy marathon runners, and the participants should be examined before and after running by using MRI. Intervention studies were excluded. RESULTS A total number of 14 studies were finally included in this review which all examined the cartilage or meniscus by using MRI functional sequences. Among them, six studies quantitatively measured the changes regarding volume of the knee cartilage or/and meniscus. Five studies found that the volume would decrease initially after running. Ten studies reported T2 (T2*) would decrease after running and returned to the baseline in a short term, while T1ρ may remain increased in months. Five studies measured subareas for T2 (T2*) value, and found that the superficial and medial subarea changed more vastly than other regions after running. CONCLUSION Runners experience transient changes in the volume and signals of knee cartilage and meniscus after long-distance running. A liquid exchange and material interaction in cartilage and meniscus was observed after running. Superficial and medial areas of knee cartilage and meniscus might be more susceptible to mechanical loading.
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Affiliation(s)
- Dingbo Shu
- School of Clinical Medicine, Hangzhou Normal University, Hangzhou, China
- Department of Radiology, Affiliated Hospital of Hangzhou Normal University, Hangzhou, China
| | - Feng Chen
- Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong, China
| | - Wentong Guo
- Department of Computer Science, City University of Hong Kong, Hong Kong, China
| | - Jianping Ding
- School of Clinical Medicine, Hangzhou Normal University, Hangzhou, China
- Department of Radiology, Affiliated Hospital of Hangzhou Normal University, Hangzhou, China
| | - Siyu Dai
- School of Clinical Medicine, Hangzhou Normal University, Hangzhou, China.
- Department of Radiology, Affiliated Hospital of Hangzhou Normal University, Hangzhou, China.
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Wu LL, Liu LH, Rao SX, Wu PY, Zhou JJ. Ultrashort time-to-echo T2* and T2* relaxometry for evaluation of lumbar disc degeneration: a comparative study. BMC Musculoskelet Disord 2022; 23:524. [PMID: 35650645 PMCID: PMC9161611 DOI: 10.1186/s12891-022-05481-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 05/24/2022] [Indexed: 11/22/2022] Open
Abstract
Background To compare potential of ultrashort time-to-echo (UTE) T2* mapping and T2* values from T2*-weighted imaging for assessing lumbar intervertebral disc degeneration (IVDD),with Pfirrmann grading as a reference standard. Methods UTE-T2* and T2* values of 366 lumbar discs (L1/2-L5/S1) in 76 subjects were measured in 3 segmented regions: anterior annulus fibrosus, nucleus pulposus (NP), and posterior annulus fibrosus. Lumbar intervertebral discs were divided into 3 categories based on 5-level Pfirrmann grading: normal (Pfirrmann grade I),early disc degeneration (Pfirrmann grades II-III), and advanced disc degeneration (Pfirrmann grades IV-V). Regional differences between UTE-T2* and T2* relaxometry and correlation with degeneration were statistically analyzed. Results UTE-T2* and T2*value correlated negatively with Pfirrmann grades (P < 0.001). In NP, correlations with Pfirrmann grade were high with UTE-T2* values (r = − 0.733; P < 0.001) and moderate with T2* values (r = -0.654; P < 0.001). Diagnostic accuracy of detecting early IVDD was better with UTE-T2* mapping than T2* mapping (P < 0.05),with receiver operating characteristic analysis area under the curve of 0.715–0.876. Conclusions UTE-T2* relaxometry provides another promising magnetic resonance imaging sequence for quantitatively evaluate lumbar IVDD and was more accurate than T2*mapping in the earlier stage degenerative process.
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Affiliation(s)
- Li-Lan Wu
- Department of Radiology, Xiamen Branch, Zhongshan Hospital, Fudan University, Xiamen, China
| | - Li-Heng Liu
- Department of Radiology, Zhongshan Hospital, Fudan University, shanghai, China.,Shanghai Institute of Medical Imaging, shanghai, China
| | - Sheng-Xiang Rao
- Department of Radiology, Zhongshan Hospital, Fudan University, shanghai, China.,Shanghai Institute of Medical Imaging, shanghai, China
| | | | - Jian-Jun Zhou
- Department of Radiology, Zhongshan Hospital, Fudan University, shanghai, China. .,Shanghai Institute of Medical Imaging, shanghai, China.
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13
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Roggenhofer E, Toumpouli E, Seeck M, Wiest R, Lutti A, Kherif F, Novy J, Rossetti AO, Draganski B. Clinical phenotype modulates brain's myelin and iron content in temporal lobe epilepsy. Brain Struct Funct 2021; 227:901-911. [PMID: 34817680 PMCID: PMC8930791 DOI: 10.1007/s00429-021-02428-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 10/21/2020] [Accepted: 11/09/2021] [Indexed: 11/17/2022]
Abstract
Temporal lobe epilepsy (TLE) is associated with brain pathology extending beyond temporal lobe structures. We sought to look for informative patterns of brain tissue properties in TLE that go beyond the established morphometry differences. We hypothesised that volume differences, particularly in hippocampus, will be paralleled by changes in brain microstructure. The cross-sectional study included TLE patients (n = 25) from a primary care center and sex-/age-matched healthy controls (n = 55). We acquired quantitative relaxometry-based magnetic resonance imaging (MRI) data yielding whole-brain maps of grey matter volume, magnetization transfer (MT) saturation, and effective transverse relaxation rate R2* indicative for brain tissue myelin and iron content. For statistical analysis, we used the computational anatomy framework of voxel-based morphometry and voxel-based quantification. There was a positive correlation between seizure activity and MT saturation measures in the ipsilateral hippocampus, paralleled by volume differences bilaterally. Disease duration correlated positively with iron content in the mesial temporal lobe, while seizure freedom was associated with a decrease of iron in the very same region. Our findings demonstrate the link between TLE clinical phenotype and brain anatomy beyond morphometry differences to show the impact of disease burden on specific tissue properties. We provide direct evidence for the differential effect of clinical phenotype characteristics on processes involving tissue myelin and iron in mesial temporal lobe structures. This study offers a proof-of-concept for the investigation of novel imaging biomarkers in focal epilepsy.
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Affiliation(s)
- Elisabeth Roggenhofer
- LREN, Centre for Research in Neuroscience, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Mont Paisible 16, 1011, Lausanne, Switzerland.,EEG and Epilepsy Unit, Department of Neurology, Department of Clinical Neurosciences, University Hospitals and Faculty of Medicine Geneva, Geneva, Switzerland
| | - Evdokia Toumpouli
- LREN, Centre for Research in Neuroscience, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Mont Paisible 16, 1011, Lausanne, Switzerland
| | - Margitta Seeck
- EEG and Epilepsy Unit, Department of Neurology, Department of Clinical Neurosciences, University Hospitals and Faculty of Medicine Geneva, Geneva, Switzerland
| | - Roland Wiest
- Support Center for Advanced Neuroimaging, Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital, University of Bern, Bern, Switzerland
| | - Antoine Lutti
- LREN, Centre for Research in Neuroscience, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Mont Paisible 16, 1011, Lausanne, Switzerland
| | - Ferath Kherif
- LREN, Centre for Research in Neuroscience, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Mont Paisible 16, 1011, Lausanne, Switzerland
| | - Jan Novy
- Service of Neurology, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Andrea O Rossetti
- Service of Neurology, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Bogdan Draganski
- LREN, Centre for Research in Neuroscience, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Mont Paisible 16, 1011, Lausanne, Switzerland. .,Service of Neurology, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland. .,Department of Neurology, Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
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14
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Wellsandt E, Emory J, Golightly YM, Dudley AT, Michaud K, Tao MA, Manzer MN, Sajja BR. Individual and cumulative measures of knee joint load associate with T2 relaxation times of knee cartilage in young, uninjured individuals: A pilot study. Knee 2021; 32:19-29. [PMID: 34371371 DOI: 10.1016/j.knee.2021.07.004] [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] [Received: 11/21/2020] [Revised: 03/25/2021] [Accepted: 07/18/2021] [Indexed: 02/02/2023]
Abstract
BACKGROUND Articular cartilage structure and chondrocyte health are sensitive and reliant on dynamic joint loading during activities. The purpose of this pilot study was to determine the association between measures of individual and cumulative knee joint loading with T2 relaxation times in the knee cartilage of young individuals without knee injury. METHODS Twelve participants (17-30 years old) without history of knee injury or surgery completed MRI, physical activity (PA), and biomechanical gait testing. T2 relaxation times were calculated in the cartilage within the patella and lateral and medial compartments. Accelerometry was used to measure mean daily step counts, minutes of PA, and % sedentary time over 7 days. Vertical ground reaction force, external knee joint moments and peak knee flexion angle were measured during stance phase of gait using three-dimensional motion capture. Cumulative knee joint loading was calculated as daily step count by external knee joint moment impulse. The relationship between measures of knee joint loading and T2 relaxation times was assessed using Pearson correlations. RESULTS Higher T2 relaxation times in the femoral and tibial cartilage were consistently correlated to greater body mass, daily step counts, moderate and vigorous PA, and peak knee joint moments (r = 0.10-0.84). Greater cumulative knee flexion and adduction loading was associated with higher T2 relaxation times in the femoral and tibial cartilage (r = 0.16-0.65). CONCLUSION Preliminary findings suggest that individual loading factors and cumulative knee joint loading are associated with higher T2 relaxation times in the articular cartilage of young, healthy knees.
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Affiliation(s)
- E Wellsandt
- Division of Physical Therapy Education, University of Nebraska Medical Center, 984420 Nebraska Medical Center, Omaha, NE 98198-4420, United States; Department of Orthopaedic Surgery and Rehabilitation, University of Nebraska Medical Center, 985640 Nebraska Medical Center, Omaha, NE 68198-5640, United States.
| | - J Emory
- College of Medicine, University of Nebraska Medical Center, 985520 Nebraska Medical Center, Omaha, NE 68198-5520, United States
| | - Y M Golightly
- Department of Epidemiology, Gillings School of Global Public Health at The University of North Carolina at Chapel Hill, 135 Dauer Drive, Chapel Hill, NC 27599-7400, United States; Thurston Arthritis Research Center, University of North Carolina at Chapel Hill, 3300 Thurston Bldg., CB#7280, Chapel Hill, NC 27599-7280, United States; Injury Prevention Research Center, University of North Carolina at Chapel Hill, 521 South Greensboro Street, Carboro, NC 27510, United States; Division of Physical Therapy, University of North Carolina at Chapel Hill, Bondurant Hall, CB #7135, Chapel Hill, NC 27599-7135, United States
| | - A T Dudley
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE 68198-5805, United States
| | - K Michaud
- Department of Internal Medicine, University of Nebraska Medical Center, 983332 Nebraska Medical Center, Omaha, NE 68198-3332, United States; Forward, The National Databank for Rheumatic Diseases, 1035 North Emporia Avenue #288, Wichita, KS 67214, United States
| | - M A Tao
- Division of Physical Therapy Education, University of Nebraska Medical Center, 984420 Nebraska Medical Center, Omaha, NE 98198-4420, United States; Department of Orthopaedic Surgery and Rehabilitation, University of Nebraska Medical Center, 985640 Nebraska Medical Center, Omaha, NE 68198-5640, United States
| | - M N Manzer
- Department of Radiology, University of Nebraska Medical Center, 981045 Nebraska Medical Center, Omaha, NE 68198-1045, United States
| | - B R Sajja
- Department of Radiology, University of Nebraska Medical Center, 981045 Nebraska Medical Center, Omaha, NE 68198-1045, United States
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15
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Okuda M, Kobayashi S, Toyooka K, Yoshimizu R, Nakase J, Hayashi H, Ueda Y, Gabata T. Quantitative differentiation of tendon and ligament using magnetic resonance imaging ultrashort echo time T2* mapping of normal knee joint. Acta Radiol 2021; 63:1489-1496. [PMID: 34558315 DOI: 10.1177/02841851211043834] [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: 11/16/2022]
Abstract
BACKGROUND Ligaments and tendons are difficult to differentiate on conventional magnetic resonance imaging (MRI). Ligaments and tendons are different histologically, and tendon graft ligamentization is known to occur after anterior cruciate ligament (ACL) reconstruction. PURPOSE To quantify and differentiate the ultrashort echo time T2* (UTE-T2*) values of normal knee ligaments and tendons using a 1.5-T MRI scanner. MATERIAL AND METHODS The right knees of 12 healthy volunteers (6 men, 6 women; mean age = 30.8 ± 9.6 years) were scanned using a UTE-T2* sequence and the UTE-T2* values of the proximal, middle, and distal portions of the ACL, posterior cruciate ligament (PCL), and patellar tendon (PT) were evaluated. Two doctors manually drew the regions of interest four times and intra- and inter-observer reliability were evaluated by intraclass correlation coefficients. RESULTS The UTE-T2* values of ACL at the proximal, middle, distal, and mean were 12.0 ± 2.3, 11.3 ± 2.3, 12.3 ± 2.6, and 11.9 ± 2.4 ms, respectively. The UTE-T2* values of the PCL at each site were 6.9 ± 1.5, 9.0 ± 1.8, 8.8 ± 2.4, and 8.3 ± 2.1 ms, respectively. The UTE-T2* values of the PT at each site were 7.1 ± 1.7, 4.3 ± 1.7, 4.3 ± 1.8, and 5.2 ± 2.1 ms, respectively. Both intra- and inter-observer reliability showed high agreement rates. There were significant differences among the ACL mean, PCL mean, and PT mean, with a P value <0.01 in all cases. CONCLUSION This study confirms that UTE-T2* mapping can quantify the ACL, PCL, and PT, and tendons and ligaments can be differentiated using the UTE-T2* values in normal volunteer knee joints.
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Affiliation(s)
- Miho Okuda
- Department of Radiology, Kanazawa University Hospital, Kanazawa, Japan
| | - Satoshi Kobayashi
- Department of Quantum Medical Technology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Kazu Toyooka
- Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Rikuto Yoshimizu
- Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Junsuke Nakase
- Department of Orthopaedic Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
| | - Hiroyuki Hayashi
- Division of Radiology, Kanazawa University Hospital, Kanazawa, Japan
| | - Yu Ueda
- MR Clinical Science, Philips Japan, Minato-ku, Japan
| | - Toshifumi Gabata
- Department of Radiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
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Abstract
Traumatic spinal cord injury is a common neurologic insult worldwide that can result in severe disability. Early stabilization of the patient's airway, breathing, and circulation as well as cervical and thoracolumbar spinal immobilization is necessary to prevent additional injury and optimize outcomes. Computed tomography (CT) scan and magnetic resonance imaging (MRI) of the spinal column can assist with determining the extent of bony and ligamentous injury, which will guide surgical management. With or without surgical intervention, patients with spinal cord injury require intensive care unit management and close observation to monitor for potential complications.
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Affiliation(s)
- Ilyas Eli
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, UT, USA; Department of Neurosurgery, Lahey Hospital and Medical Center, Burlington, MA, USA
| | - David P Lerner
- Department of Neurology, Lahey Hospital and Medical Center, Burlington, MA, USA
| | - Zoher Ghogawala
- Department of Neurosurgery, Lahey Hospital and Medical Center, Burlington, MA, USA.
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Tan ET, Queler SC, Lin B, Endo Y, Burge AJ, Sternberg J, Potter HG, Sneag DB. Improved nerve conspicuity with water-weighting and denoising in two-point Dixon magnetic resonance neurography. Magn Reson Imaging 2021; 79:103-111. [PMID: 33753136 DOI: 10.1016/j.mri.2021.03.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 12/09/2020] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND T2-weighted, two-point Dixon fast-spin-echo (FSE) is an effective technique for magnetic resonance neurography (MRN) that can provide quantitative assessment of muscle denervation. Low signal-to-noise ratio and inadequate fat suppression, however, can impede accurate interpretation. PURPOSE To quantify effects of principal component analysis (PCA) denoising on tissue signal intensities and fat fraction (FF) and to determine qualitative image quality improvements from both denoising and water-weighting (WW) algorithms to improve nerve conspicuity and fat suppression. STUDY TYPE Prospective. SUBJECTS Twenty-one subjects undergoing MR neurography evaluation (11/10 male/female, mean age = 46.3±13.7 years) with 60 image volumes. Twelve subjects (23 image volumes) were determined to have muscle denervation based on diffusely elevated T2 signal intensity. FIELD STRENGTH/SEQUENCE 3 T, 2D, two-point Dixon FSE. ASSESSMENT Qualitative assessment included overall image quality, nerve conspicuity, fat suppression, pulsation and ringing artifacts by 3 radiologists separately on a three-point scale (1 = poor, 2 = average, 3 = excellent). Quantitative measurements for FF and signal intensity relative to normal muscle were made for nerve, abnormal muscle and subcutaneous fat. STATISTICAL TESTS Linear and ordinal regression models were used for quantitative and qualitative comparisons, respectively; 95% confidence intervals (CIs) and p-values for pairwise comparisons were adjusted using the Holm-Bonferroni method. Inter-rater agreement was assessed using Gwet's agreement coefficient (AC2). RESULTS Simulations showed PCA-denoising reduced FF error from 2.0% to 1.0%, and from 7.6% to 3.1% at noise levels of 10% and 30%, respectively. In human subjects, PCA-denoising did not change signal levels and FF quantitatively. WW decreased fat signal significantly (-83.6%, p < 0.001). Nerve conspicuity was improved by WW (odds ratio, OR = 5.8, p < 0.001). Fat suppression was improved by both PCA (OR = 3.6, p < 0.001) and WW (OR = 2.2, p < 0.001). Overall image quality was improved by PCA + WW (OR = 1.7, p = 0.04). CONCLUSIONS WW and PCA-denoising improved nerve conspicuity and fat suppression in MR neurography. Denoising can potentially provide improved accuracy of FF maps for assessing fat-infiltrated muscle.
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Affiliation(s)
- Ek T Tan
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA.
| | - Sophie C Queler
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Bin Lin
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Yoshimi Endo
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Alissa J Burge
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Julia Sternberg
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Hollis G Potter
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Darryl B Sneag
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
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Trofimova O, Loued-Khenissi L, DiDomenicantonio G, Lutti A, Kliegel M, Stringhini S, Marques-Vidal P, Vollenweider P, Waeber G, Preisig M, Kherif F, Draganski B. Brain tissue properties link cardio-vascular risk factors, mood and cognitive performance in the CoLaus|PsyCoLaus epidemiological cohort. Neurobiol Aging 2021; 102:50-63. [PMID: 33765431 DOI: 10.1016/j.neurobiolaging.2021.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 01/31/2021] [Accepted: 02/04/2021] [Indexed: 01/15/2023]
Abstract
Given the controversy about the impact of modifiable risk factors on mood and cognition in ageing, we sought to investigate the associations between cardio-vascular risk, mental health, cognitive performance and brain anatomy in mid- to old age. We analyzed a set of risk factors together with multi-parameter magnetic resonance imaging (MRI) in the CoLaus|PsyCoLaus cohort (n > 1200). Cardio-vascular risk was associated with differences in brain tissue properties - myelin, free tissue water, iron content - and regional brain volumes that we interpret in the context of micro-vascular hypoxic lesions and neurodegeneration. The interaction between clinical subtypes of major depressive disorder and cardio-vascular risk factors showed differential associations with brain structure depending on individuals' lifetime trajectory. There was a negative correlation between melancholic depression, anxiety and MRI markers of myelin and iron content in the hippocampus and anterior cingulate. Verbal memory and verbal fluency performance were positively correlated with left amygdala volumes. The concomitant analysis of brain morphometry and tissue properties allowed for a neuro-biological interpretation of the link between modifiable risk factors and brain health.
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Steenkjaer CH, Mencagli RA, Vaeggemose M, Andersen H. Isokinetic strength and degeneration of lower extremity muscles in patients with myotonic dystrophy; an MRI study. Neuromuscul Disord 2021; 31:198-211. [PMID: 33568272 DOI: 10.1016/j.nmd.2020.12.011] [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: 05/17/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 01/10/2023]
Abstract
Our aim was to determine isokinetic strength and degeneration of lower extremity muscles in patients with Myotonic Dystrophy (DM1). In 19 patients with DM1 and 19 matched controls, strength measured by isokinetic dynamometry was expressed as percentage of expected strength (ePct), adjusted for age, height, weight and gender. MRI of the hip, thigh and calf muscles were obtained. Fat fraction (FF), mean contractile cross-sectional area (cCSA) and specific strength (Nm/cm2) were calculated. Patients' ankle plantar flexors, knee flexors and extensors had higher FF (Δ: 0.08 - 0.42) and lower cCSA (Δ: 3.2 -17.1 cm2) compared to controls (p ≤ 0.005). EPct (Δ: 19.5 - 41.6%) and specific strength (Δ: 0.27 - 0.96 Nm/cm2) were lower in the majority of patients muscle groups (p˂0.05). Close correlations were found for patients when relating ePct to; FF for plantar flexors (R2=0.742, p<0.001) and knee extensors (R2=0.732, p<0.001), cCSA for plantar flexors (R2=0.696, p<0.001) and knee extensors (R2=0.633, p<0.001), and specific strength for dorsal flexors (ρ=0.855, p = 0.008). In conclusion, patients had weaker lower extremity muscles with higher FF, lower cCSA and specific strength compared to controls. Muscle degeneration determined by quantitative MRI strongly correlated to strength supporting its feasibility to quantify muscle dysfunction in DM1.
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Affiliation(s)
- C H Steenkjaer
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark.
| | - R A Mencagli
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
| | - M Vaeggemose
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
| | - H Andersen
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
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Schoemaker D, Zuluaga Y, Viswanathan A, Shrimer D, Torrico-Teave H, Velilla L, Ospina C, Ospina GG, Lopera F, Arboleda-Velasquez JF, Quiroz YT. The INECO Frontal Screening for the Evaluation of Executive Dysfunction in Cerebral Small Vessel Disease: Evidence from Quantitative MRI in a CADASIL Cohort from Colombia. J Int Neuropsychol Soc 2020; 26:1006-18. [PMID: 32487276 DOI: 10.1017/S1355617720000533] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVES Executive dysfunction is a predominant cognitive symptom in cerebral small vessel disease (SVD). The Institute of Cognitive Neurology Frontal Screening (IFS) is a well-validated screening tool allowing the rapid assessment of multiple components of executive function in Spanish-speaking individuals. In this study, we examined performance on the IFS in subjects with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), an inherited condition leading to the early onset of SVD. We further explored associations between performance on the IFS and magnetic resonance imaging (MRI) markers of SVD. METHODS We recruited 24 asymptomatic CADASIL subjects and 23 noncarriers from Colombia. All subjects underwent a research MRI and a neuropsychological evaluation, including the IFS. Structural MRI markers of SVD were quantified in each subject, together with an SVD Sum Score representing the overall burden of cerebrovascular alterations. General linear model, correlation, and receiver operating characteristic curve analyses were used to explore group differences on the IFS and relationships with MRI markers of SVD. RESULTS CADASIL subjects had a significantly reduced performance on the IFS Total Score. Performance on the IFS correlated with all quantified markers of SVD, except for brain atrophy and perivascular spaces enlargement. Finally, while the IFS Total Score was not able to accurately discriminate between carriers and noncarriers, it showed adequate sensitivity and specificity in detecting the presence of multiple MRI markers of SVD. CONCLUSIONS These results suggest that the IFS may be a useful screening tool to assess executive function and disease severity in the context of SVD.
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Boonzaier NR, Hales PW, D'Arco F, Walters BC, Kaur R, Mankad K, Cooper J, Liasis A, Smith V, O'Hare P, Hargrave D, Clark CA. Quantitative MRI demonstrates abnormalities of the third ventricle subventricular zone in neurofibromatosis type-1 and sporadic paediatric optic pathway glioma. Neuroimage Clin 2020; 28:102447. [PMID: 33038669 PMCID: PMC7554210 DOI: 10.1016/j.nicl.2020.102447] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 09/17/2020] [Accepted: 09/20/2020] [Indexed: 11/26/2022]
Abstract
MRI provides supporting evidence of third ventricle subventricular involvement in OPG. Third ventricle subventricular zone ADC and CBF differs between NF1 and sporadic OPG. Third ventricle subventricular zone ADC correlates with vision in sporadic OPG.
Background The subventricular zone of the third ventricle (TVZ) is a germinal stem cell niche, identified as the possible location of optic pathway glioma (OPG) cell origin. Paediatric OPGs are predominantly diagnosed as low-grade astrocytomas, which are either sporadic or are associated with neurofibromatosis type-1 (NF1). These tumours often cause a significant impairment to visual acuity (VA). Infiltrative/invasive tumour activity is associated with increased apparent diffusion coefficient (ADC) and cerebral blood flow (CBF). This study aimed to determine whether TVZ imaging features differed between sporadic-OPG, NF1-OPG and controls, and whether the ADC and CBF profile at the germinal stem cell niche (the TVZ) correlated with the primary outcome of VA. Methods ADC and CBF MRI data were acquired from 30 paediatric OPG patients (median age 6 years; range 8 months–17 years), along with VA measurements, during clinical surveillance of their tumour. Values for mean ADC and maximum CBF were measured at the TVZ, and normalized to normal-appearing grey matter. These values were compared between the two OPG groups and the healthy control subjects, and multivariate linear regression was used to test the linear association between these values and patient’s VA. Results In the TVZ, normalized mean ADC was higher in NF1-associated OPG patients (N = 15), compared to both sporadic OPG patients (N = 15; p = 0.010) and healthy controls (N = 14; p < 0.001). In the same region, normalized maximum CBF was higher in sporadic OPG patients compared to both NF1-OPG patients (p = 0.016) and healthy controls (p < 0.001). In sporadic OPG patients only, normalized mean ADC in the TVZ was significantly correlated with visual acuity (R2 = 0.41, p = 0.019). No significant correlations were found between TVZ CBF and ADC values and visual acuity in the NF1-associated OPG patients. Conclusion Quantitative MRI detects TVZ abnormalities in both sporadic and NF1-OPG patients, and identifies TVZ features that differentiate the two. TVZ features may be useful MRI markers of interest in future predictive studies involving sporadic OPG.
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Affiliation(s)
- Natalie R Boonzaier
- Developmental Imaging and Biophysics Section, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, UK
| | - Patrick W Hales
- Developmental Imaging and Biophysics Section, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, UK.
| | - Felice D'Arco
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Bronwen C Walters
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Ramneek Kaur
- Developmental Imaging and Biophysics Section, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, UK
| | - Kshitij Mankad
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Jessica Cooper
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Alki Liasis
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK; University of Pittsburgh Medical Center, Children's Hospital of Pittsburgh, Pittsburgh, USA
| | - Victoria Smith
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Patricia O'Hare
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Darren Hargrave
- Developmental Imaging and Biophysics Section, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, UK; Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Christopher A Clark
- Developmental Imaging and Biophysics Section, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, UK
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Seiler A, Brandhofe A, Gracien RM, Pfeilschifter W, Hattingen E, Deichmann R, Nöth U, Wagner M. Microstructural Alterations Analogous to Accelerated Aging of the Cerebral Cortex in Carotid Occlusive Disease. Clin Neuroradiol 2020; 31:709-720. [PMID: 32638029 PMCID: PMC8463359 DOI: 10.1007/s00062-020-00928-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [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: 01/14/2020] [Accepted: 06/10/2020] [Indexed: 11/28/2022]
Abstract
Purpose To investigate cortical thickness and cortical quantitative T2 values as imaging markers of microstructural tissue damage in patients with unilateral high-grade internal carotid artery occlusive disease (ICAOD). Methods A total of 22 patients with ≥70% stenosis (mean age 64.8 years) and 20 older healthy control subjects (mean age 70.8 years) underwent structural magnetic resonance imaging (MRI) and high-resolution quantitative (q)T2 mapping. Generalized linear mixed models (GLMM) controlling for age and white matter lesion volume were employed to investigate the effect of ICAOD on imaging parameters of cortical microstructural integrity in multivariate analyses. Results There was a significant main effect (p < 0.05) of the group (patients/controls) on both cortical thickness and cortical qT2 values with cortical thinning and increased cortical qT2 in patients compared to controls, irrespective of the hemisphere. The presence of upstream carotid stenosis had a significant main effect on cortical qT2 values (p = 0.01) leading to increased qT2 in the poststenotic hemisphere, which was not found for cortical thickness. The GLMM showed that in general cortical thickness was decreased and cortical qT2 values were increased with increasing age (p < 0.05). Conclusion Unilateral high-grade carotid occlusive disease is associated with widespread cortical thinning and prolongation of cortical qT2, presumably reflecting hypoperfusion-related microstructural cortical damage similar to accelerated aging of the cerebral cortex. Cortical thinning and increase of cortical qT2 seem to reflect different aspects and different pathophysiological states of cortical degeneration. Quantitative T2 mapping might be a sensitive imaging biomarker for early cortical microstructural damage.
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Affiliation(s)
- Alexander Seiler
- Department of Neurology, Goethe University Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany. .,Brain Imaging Center, Goethe University Frankfurt, Frankfurt, Germany.
| | - Annemarie Brandhofe
- Department of Neurology, Goethe University Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany.,Brain Imaging Center, Goethe University Frankfurt, Frankfurt, Germany
| | - René-Maxime Gracien
- Department of Neurology, Goethe University Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany.,Brain Imaging Center, Goethe University Frankfurt, Frankfurt, Germany
| | - Waltraud Pfeilschifter
- Department of Neurology, Goethe University Frankfurt, Schleusenweg 2-16, 60528, Frankfurt, Germany
| | - Elke Hattingen
- Institute of Neuroradiology, Goethe University Frankfurt, Frankfurt, Germany
| | - Ralf Deichmann
- Brain Imaging Center, Goethe University Frankfurt, Frankfurt, Germany
| | - Ulrike Nöth
- Brain Imaging Center, Goethe University Frankfurt, Frankfurt, Germany
| | - Marlies Wagner
- Institute of Neuroradiology, Goethe University Frankfurt, Frankfurt, Germany
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Fields BKK, Hwang D, Cen S, Desai B, Gulati M, Hu J, Duddalwar V, Varghese B, Matcuk GR Jr. Quantitative magnetic resonance imaging (q-MRI) for the assessment of soft-tissue sarcoma treatment response: a narrative case review of technique development. Clin Imaging 2020; 63:83-93. [PMID: 32163847 DOI: 10.1016/j.clinimag.2020.02.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 11/20/2022]
Abstract
Soft-tissue sarcomas are a heterogeneous class of tumors that exhibit varying degrees of cellularity and cystic degeneration in response to neoadjuvant chemotherapy. This creates unique challenges in the radiographic assessment of treatment response when relying on conventional markers such as tumor diameter (RECIST criteria). In this case series, we provide a narrative discussion of technique development for whole tumor volume quantitative magnetic resonance imaging (q-MRI), highlighting cases from a small pilot study of 8 patients (9 tumors) pre- and post-neoadjuvant chemotherapy. One of the methods of q-MRI analysis (the "constant-cutoff" technique) was able to predict responders versus non-responders based on percent necrosis and viable tumor volume calculations (p = 0.05), respectively. Our results suggest that q-MRI of whole tumor volume contrast enhancement may have a role in tumor response assessment, although further validation is needed.
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Haacke EM, Chen Y, Utriainen D, Wu B, Wang Y, Xia S, He N, Zhang C, Wang X, Lagana MM, Luo Y, Fatemi A, Liu S, Gharabaghi S, Wu D, Sethi SK, Huang F, Sun T, Qu F, Yadav BK, Ma X, Bai Y, Wang M, Cheng J, Yan F. STrategically Acquired Gradient Echo (STAGE) imaging, part III: Technical advances and clinical applications of a rapid multi-contrast multi-parametric brain imaging method. Magn Reson Imaging 2019; 65:15-26. [PMID: 31629075 DOI: 10.1016/j.mri.2019.09.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [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: 06/16/2019] [Revised: 09/11/2019] [Accepted: 09/15/2019] [Indexed: 12/15/2022]
Abstract
One major thrust in radiology today is image standardization with a focus on rapidly acquired quantitative multi-contrast information. This is critical for multi-center trials, for the collection of big data and for the use of artificial intelligence in evaluating the data. Strategically acquired gradient echo (STAGE) imaging is one such method that can provide 8 qualitative and 7 quantitative pieces of information in 5 min or less at 3 T. STAGE provides qualitative images in the form of proton density weighted images, T1 weighted images, T2* weighted images and simulated double inversion recovery (DIR) images. STAGE also provides quantitative data in the form of proton spin density, T1, T2* and susceptibility maps as well as segmentation of white matter, gray matter and cerebrospinal fluid. STAGE uses vendors' product gradient echo sequences. It can be applied from 0.35 T to 7 T across all manufacturers producing similar results in contrast and quantification of the data. In this paper, we discuss the strengths and weaknesses of STAGE, demonstrate its contrast-to-noise (CNR) behavior relative to a large clinical data set and introduce a few new image contrasts derived from STAGE, including DIR images and a new concept referred to as true susceptibility weighted imaging (tSWI) linked to fluid attenuated inversion recovery (FLAIR) or tSWI-FLAIR for the evaluation of multiple sclerosis lesions. The robustness of STAGE T1 mapping was tested using the NIST/NIH phantom, while the reproducibility was tested by scanning a given individual ten times in one session and the same subject scanned once a week over a 12-week period. Assessment of the CNR for the enhanced T1W image (T1WE) showed a significantly better contrast between gray matter and white matter than conventional T1W images in both patients with Parkinson's disease and healthy controls. We also present some clinical cases using STAGE imaging in patients with stroke, metastasis, multiple sclerosis and a fetus with ventriculomegaly. Overall, STAGE is a comprehensive protocol that provides the clinician with numerous qualitative and quantitative images.
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Affiliation(s)
- E Mark Haacke
- Department of Radiology, Wayne State University School of Medicine, Detroit, MI, USA; The MRI Institute for Biomedical Research, Bingham Farms, MI, USA; Magnetic Resonance Innovations, Inc., Bingham Farms, MI, USA.
| | - Yongsheng Chen
- Department of Radiology, Wayne State University School of Medicine, Detroit, MI, USA; Department of Neurology, Wayne State University School of Medicine, Detroit, MI, USA
| | - David Utriainen
- The MRI Institute for Biomedical Research, Bingham Farms, MI, USA; Magnetic Resonance Innovations, Inc., Bingham Farms, MI, USA
| | - Bo Wu
- Magnetic Resonance Innovations, Inc., Bingham Farms, MI, USA
| | - Yu Wang
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, Shanghai, China; Neusoft Medical Systems Co., Ltd., Shanghai, China
| | - Shuang Xia
- Department of Radiology, Tianjin First Central Hospital, Tianjin, China
| | - Naying He
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chunyan Zhang
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xiao Wang
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | | | - Yu Luo
- Department of Radiology, Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, Shanghai, China
| | - Ali Fatemi
- Departments of Radiology and Radiation Oncology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Saifeng Liu
- The MRI Institute for Biomedical Research, Bingham Farms, MI, USA
| | - Sara Gharabaghi
- Magnetic Resonance Innovations, Inc., Bingham Farms, MI, USA
| | - Dongmei Wu
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, Shanghai, China
| | - Sean K Sethi
- Department of Radiology, Wayne State University School of Medicine, Detroit, MI, USA; The MRI Institute for Biomedical Research, Bingham Farms, MI, USA; Magnetic Resonance Innovations, Inc., Bingham Farms, MI, USA
| | - Feng Huang
- Neusoft Medical Systems Co., Ltd., Shanghai, China
| | - Taotao Sun
- Department of Radiology, International Peace Maternity and Child Health Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Feifei Qu
- Department of Radiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Brijesh K Yadav
- Department of Radiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Xiaoyue Ma
- Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China; Department of Radiology, Zhengzhou University People's Hospital, Zhengzhou, China
| | - Yan Bai
- Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China; Department of Radiology, Zhengzhou University People's Hospital, Zhengzhou, China
| | - Meiyun Wang
- Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China; Department of Radiology, Zhengzhou University People's Hospital, Zhengzhou, China.
| | - Jingliang Cheng
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Fuhua Yan
- Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Köhler C, Wahl H, Ziemssen T, Linn J, Kitzler HH. Exploring individual multiple sclerosis lesion volume change over time: Development of an algorithm for the analyses of longitudinal quantitative MRI measures. Neuroimage Clin 2018; 21:101623. [PMID: 30545687 PMCID: PMC6411650 DOI: 10.1016/j.nicl.2018.101623] [Citation(s) in RCA: 10] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 11/01/2018] [Accepted: 12/01/2018] [Indexed: 01/28/2023]
Abstract
Background Magnetic resonance imaging (MRI) is used to follow-up multiple sclerosis (MS) and evaluate disease progression and therapy response via lesion quantification. However, there is a lack of automated post-processing techniques to quantify individual MS lesion change. Objective The present study developed a secondary post-processing algorithm for MS lesion segmentation routine to quantify individual changes in volume over time. Methods An Automatic Follow-up of Individual Lesions (AFIL) algorithm was developed to process time series of pre-segmented binary lesion masks. The resulting consistently labelled lesion masks allowed for the evaluation of individual lesion volumes. Algorithm performance testing was executed in seven early MS patients with four MRI visits, and MS experienced readers verified the accuracy. Results AFIL distinguished 328 individual MS lesions with a 0.9% error rate to track persistent or new lesions based on expert assessment. A total of 121 new lesions evolved within the observed time period. The proportional courses of 69.1% lesions in the persistent lesion population exhibited varying volume, 16.9% exhibited stable volume, 3.4% exhibiting continuously increasing, and 0.5% exhibited continuously decreasing volume. Conclusion This algorithm tracked individual lesions to automatically create an individual lesion growth profile of MS patients. This approach may allow for characterization of patients based on their individual lesion progression. This algorithm can be used for individual tracking of lesion volumes or can read-out parameter changes of quantitative MR images in lesions. This method allows the characterization of patients based on their individual lesion growth profile. In early MS most lesions had varying volume, few were stable, and very few increased or decreased continuously.
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Affiliation(s)
- Caroline Köhler
- Dept. of Neuroradiology, University Hospital Carl Gustav Carus', Technische Universität Dresden, Dresden, SN, Germany.
| | - Hannes Wahl
- Dept. of Neuroradiology, University Hospital Carl Gustav Carus', Technische Universität Dresden, Dresden, SN, Germany
| | - Tjalf Ziemssen
- Dept. of Neurology, University Hospital Carl Gustav Carus', Technische Universität Dresden, Dresden, SN, Germany
| | - Jennifer Linn
- Dept. of Neuroradiology, University Hospital Carl Gustav Carus', Technische Universität Dresden, Dresden, SN, Germany
| | - Hagen H Kitzler
- Dept. of Neuroradiology, University Hospital Carl Gustav Carus', Technische Universität Dresden, Dresden, SN, Germany
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Nachmani A, Schurr R, Joskowicz L, Mezer AA. The effect of motion correction interpolation on quantitative T1 mapping with MRI. Med Image Anal 2018; 52:119-127. [PMID: 30529225 DOI: 10.1016/j.media.2018.11.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [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: 04/07/2018] [Revised: 11/29/2018] [Accepted: 11/30/2018] [Indexed: 11/16/2022]
Abstract
Quantitative magnetic resonance imaging (qMRI) is a technique for mapping the physical properties of the underlying tissue using several MR images with different contrasts. To overcome subject motion between the acquired images, it is necessary to register the images to a common reference frame. A drawback of registration is the use of interpolation and resampling techniques, which can introduce artifacts into the interpolated data. These artifacts could have unfavorable effects on the accuracy of the estimated tissue's physical properties. Here, we quantified the error of interpolation and resampling on T1-weighted images and studied its effects on the mapping of the longitudinal relaxation time (T1) using variable flip angles. We simulated T1-weighted images and calculated the transformation error resulting from interpolation and resampling. We found that the error is a function of the image contrast (i.e., flip angle) and of the translation and rotation of the image. Furthermore, we found that the error in the T1-weighted images has a substantial effect on the T1 estimation, of the order of 10% of the signal in the brain's gray and white matter. Hence, minimizing the registration error can enable more accurate in vivo modeling of brain microstructure.
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Affiliation(s)
- Amitay Nachmani
- The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Israel; The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Israel
| | - Roey Schurr
- The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Israel
| | - Leo Joskowicz
- The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Israel; The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Israel
| | - Aviv A Mezer
- The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Israel.
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Knox J, Pedoia V, Wang A, Tanaka M, Joseph GB, Neumann J, Link TM, Li X, Ma CB. Longitudinal changes in MR T1ρ/T2 signal of meniscus and its association with cartilage T1p/T2 in ACL-injured patients. Osteoarthritis Cartilage 2018; 26:689-96. [PMID: 29438746 DOI: 10.1016/j.joca.2018.02.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 01/30/2018] [Accepted: 02/05/2018] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To evaluate the longitudinal changes in meniscal T1ρ/T2 signal post-reconstruction in patients with acute anterior cruciate ligament (ACL) injury and to investigate the association with T1ρ/T2 signal in articular knee cartilage. METHOD In this prospective study, knees of 37 patients with ACL-injury and reconstruction in addition to 13 healthy controls were scanned using magnetic resonance imaging (MRI) T1ρ/T2 mapping. Quantitative analysis of the meniscus was performed in the anterior/posterior horns of lateral/medial meniscus fourteen sub-compartments of cartilage spanning the medial/lateral area of the tibia and femoral condyles. Meniscus T1ρ/T2 signals were compared between injured, contralateral and control knees at baseline, 6-months, 1-year and 2-years using t-tests for cross-sectional comparisons and a mixed model for longitudinal comparisons. Pearson-partial correlations between meniscal and cartilage T1ρ/T2 were evaluated. RESULTS There was a significant decrease of T1ρ/T2 signal in the posterior horn of lateral meniscus (PHLAT) of injured knees during a 2-year period. In the posterior horn of medial meniscus (PHMED), T1ρ/T2 signal of injured knees was significantly elevated at all time points post-reconstruction compared to contralateral and control knees. Within injured knees, PHMED T1ρ/T2 signal showed significant positive correlations with medial tibia (MT) cartilage T1ρ/T2 signal at all time points. CONCLUSION A significant decrease in PHLAT T1ρ/T2 signal by 2-years suggests potential tissue recovery after ACL-injury. Elevated T1ρ/T2 signal in the PHMED of injured knees at 2-years correlating with knee cartilage T1ρ/T2 signal elevations suggests involvement of the PHMED in subacute cartilage degeneration after ACL-injury and reconstruction.
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Whittaker HT, Zhu S, Di Curzio DL, Buist R, Li XM, Noy S, Wiseman FK, Thiessen JD, Martin M. T 1, diffusion tensor, and quantitative magnetization transfer imaging of the hippocampus in an Alzheimer's disease mouse model. Magn Reson Imaging 2018; 50:26-37. [PMID: 29545212 DOI: 10.1016/j.mri.2018.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [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: 02/09/2018] [Accepted: 03/10/2018] [Indexed: 01/08/2023]
Abstract
Alzheimer's disease (AD) pathology causes microstructural changes in the brain. These changes, if quantified with magnetic resonance imaging (MRI), could be studied for use as an early biomarker for AD. The aim of our study was to determine if T1 relaxation, diffusion tensor imaging (DTI), and quantitative magnetization transfer imaging (qMTI) metrics could reveal changes within the hippocampus and surrounding white matter structures in ex vivo transgenic mouse brains overexpressing human amyloid precursor protein with the Swedish mutation. Delineation of hippocampal cell layers using DTI color maps allows more detailed analysis of T1-weighted imaging, DTI, and qMTI metrics, compared with segmentation of gross anatomy based on relaxation images, and with analysis of DTI or qMTI metrics alone. These alterations are observed in the absence of robust intracellular Aβ accumulation or plaque deposition as revealed by histology. This work demonstrates that multiparametric quantitative MRI methods are useful for characterizing changes within the hippocampal substructures and surrounding white matter tracts of mouse models of AD.
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Affiliation(s)
- Heather T Whittaker
- Biopsychology, University of Winnipeg, Winnipeg, MB R3B 2N2, Canada; Neurodegenerative Disease, University College London Institute of Neurology, London WC1N 3BG, United Kingdom.
| | - Shenghua Zhu
- Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB R3E 0T6, Canada
| | | | - Richard Buist
- Radiology, University of Manitoba, Winnipeg, MB R3E 0T6, Canada
| | - Xin-Min Li
- Psychiatry, University of Alberta, Alberta T6G 2R3, Canada
| | - Suzanna Noy
- Neurodegenerative Disease, University College London Institute of Neurology, London WC1N 3BG, United Kingdom
| | - Frances K Wiseman
- Neurodegenerative Disease, University College London Institute of Neurology, London WC1N 3BG, United Kingdom
| | - Jonathan D Thiessen
- Imaging Program, Lawson Health Research Institute, London, ON N6A 4V2, Canada; Medical Biophysics, Western University, London, Ontario, Canada
| | - Melanie Martin
- Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB R3E 0T6, Canada; Radiology, University of Manitoba, Winnipeg, MB R3E 0T6, Canada; Physics, University of Winnipeg, R3B 2N2, Canada
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Kline TL, Edwards ME, Garg I, Irazabal MV, Korfiatis P, Harris PC, King BF, Torres VE, Venkatesh SK, Erickson BJ. Quantitative MRI of kidneys in renal disease. Abdom Radiol (NY) 2018; 43:629-638. [PMID: 28660330 DOI: 10.1007/s00261-017-1236-y] [Citation(s) in RCA: 29] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To evaluate the reproducibility and utility of quantitative magnetic resonance imaging (MRI) sequences for the assessment of kidneys in young adults with normal renal function (eGFR ranged from 90 to 130 mL/min/1.73 m2) and patients with early renal disease (autosomal dominant polycystic kidney disease). MATERIALS AND METHODS This prospective case-control study was performed on ten normal young adults (18-30 years old) and ten age- and sex-matched patients with early renal parenchymal disease (autosomal dominant polycystic kidney disease). All subjects underwent a comprehensive kidney MRI protocol, including qualitative imaging: T1w, T2w, FIESTA, and quantitative imaging: 2D cine phase contrast of the renal arteries, and parenchymal diffusion weighted imaging (DWI), magnetization transfer imaging (MTI), blood oxygen level dependent (BOLD) imaging, and magnetic resonance elastography (MRE). The normal controls were imaged on two separate occasions ≥24 h apart (range 24-210 h) to assess reproducibility of the measurements. RESULTS Quantitative MR imaging sequences were found to be reproducible. The mean ± SD absolute percent difference between quantitative parameters measured ≥24 h apart were: MTI-derived ratio = 4.5 ± 3.6%, DWI-derived apparent diffusion coefficient (ADC) = 6.5 ± 3.4%, BOLD-derived R2* = 7.4 ± 5.9%, and MRE-derived tissue stiffness = 7.6 ± 3.3%. Compared with controls, the ADPKD patient's non-cystic renal parenchyma (NCRP) had statistically significant differences with regard to quantitative parenchymal measures: lower MTI percent ratios (16.3 ± 4.4 vs. 23.8 ± 1.2, p < 0.05), higher ADCs (2.46 ± 0.20 vs. 2.18 ± 0.10 × 10-3 mm2/s, p < 0.05), lower R2*s (14.9 ± 1.7 vs. 18.1 ± 1.6 s-1, p < 0.05), and lower tissue stiffness (3.2 ± 0.3 vs. 3.8 ± 0.5 kPa, p < 0.05). CONCLUSION Excellent reproducibility of the quantitative measurements was obtained in all cases. Significantly different quantitative MR parenchymal measurement parameters between ADPKD patients and normal controls were obtained by MT, DWI, BOLD, and MRE indicating the potential for detecting and following renal disease at an earlier stage than the conventional qualitative imaging techniques.
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Affiliation(s)
- Timothy L Kline
- Department of Radiology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, 55905, MN, USA.
| | - Marie E Edwards
- Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Ishan Garg
- Department of Radiology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, 55905, MN, USA
| | - Maria V Irazabal
- Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Panagiotis Korfiatis
- Department of Radiology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, 55905, MN, USA
| | - Peter C Harris
- Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Bernard F King
- Department of Radiology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, 55905, MN, USA
| | - Vicente E Torres
- Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Sudhakar K Venkatesh
- Department of Radiology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, 55905, MN, USA
| | - Bradley J Erickson
- Department of Radiology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, 55905, MN, USA
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Abstract
Magnetization transfer contrast has yielded insight into brain tissue microstructure changes across the lifespan and in a range of disorders. This progress has been aided by the development of quantitative magnetization transfer imaging techniques able to extract intrinsic properties of the tissue that are independent of the specifics of the data acquisition. While the tissue properties extracted by these techniques do not map directly onto specific cellular structures or pathological processes, a growing body of work from animal models and histopathological correlations aids the in vivo interpretation of magnetization transfer properties of tissue. This review examines the biophysical models that have been developed to describe magnetization transfer contrast in tissue as well as the experimental evidence for the biological interpretation of magnetization transfer data in health and disease.
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Affiliation(s)
- John G Sled
- Hospital for Sick Children, Mouse Imaging Centre, Toronto, Ontario, Canada; Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
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Yin T, Liu Y, Peeters R, Feng Y, Ni Y. Pancreatic imaging: Current status of clinical practices and small animal studies. World J Methodol 2017; 7:101-107. [PMID: 29026690 PMCID: PMC5618143 DOI: 10.5662/wjm.v7.i3.101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 08/22/2017] [Accepted: 09/04/2017] [Indexed: 02/06/2023] Open
Abstract
Different causative factors acting on the pancreas can result in diseases such as pancreatitis, diabetes and pancreatic tumors. The high incidence and mortality of pancreatic diseases have placed diagnostic imaging in a crucial position in daily clinical practice. In this mini-review article different pancreatic imaging techniques are discussed, from the standard clinical imaging modalities and state of the art clinical magnetic resonance imaging techniques to current situations in pre-clinical pancreatic imaging studies. In particular, the challenges of pre-clinical rodent pancreatic imaging are addressed, with both the image acquisition techniques and the post-processing methods for rodent pancreatic imaging elaborated.
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Affiliation(s)
- Ting Yin
- Department of Imaging and Pathology, Biomedical Sciences Group, KU Leuven, 3000 Leuven, Belgium
| | - Yewei Liu
- Department of Imaging and Pathology, Biomedical Sciences Group, KU Leuven, 3000 Leuven, Belgium
| | - Ronald Peeters
- Department of Imaging and Pathology, Biomedical Sciences Group, KU Leuven, 3000 Leuven, Belgium
| | - Yuanbo Feng
- Department of Imaging and Pathology, Biomedical Sciences Group, KU Leuven, 3000 Leuven, Belgium
| | - Yicheng Ni
- Department of Imaging and Pathology, Biomedical Sciences Group, KU Leuven, 3000 Leuven, Belgium
- Department of Radiology, University Hospitals, KU Leuven, 3000 Leuven, Belgium
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Abstract
BACKGROUND Current computational neuroanatomy focuses on morphological measurements of the brain using standard magnetic resonance imaging (MRI) techniques. In comparison quantitative MRI (qMRI) typically provides a better tissue contrast and also greatly improves the sensitivity and specificity with respect to the microstructural characteristics of tissue. OBJECTIVE Current methodological developments in qMRI are presented, which go beyond morphology because this provides standardized measurements of the microstructure of the brain. The concept of in-vivo histology is introduced, based on biophysical modelling of qMRI data (hMRI) for determination of quantitative histology-like markers of the microstructure. RESULTS The qMRI metrics can be used as direct biomarkers of the microstructural mechanisms driving observed morphological findings. The hMRI metrics utilize biophysical models of the MRI signal in order to determine 3‑dimensional maps of histology-like measurements in the white matter. CONCLUSION Non-invasive brain tissue characterization using qMRI or hMRI has significant implications for both scientific and clinical applications. Both approaches improve the comparability across sites and time points, facilitate multicenter and longitudinal studies as well as standardized diagnostics. The hMRI is expected to shed new light on the relationship between brain microstructure, function and behavior both in health and disease. In the future hMRI will play an indispensable role in the field of computational neuroanatomy.
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Affiliation(s)
- S Mohammadi
- Institut für systemische Neurowissenschaften, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Deutschland
- Max-Planck-Institut für Kognitions- und Neurowissenschaften, Stephanstr. 1a, 04103, Leipzig, Deutschland
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London, Großbritannien
| | - N Weiskopf
- Max-Planck-Institut für Kognitions- und Neurowissenschaften, Stephanstr. 1a, 04103, Leipzig, Deutschland.
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London, Großbritannien.
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Andescavage NN, DuPlessis A, McCarter R, Vezina G, Robertson R, Limperopoulos C. Cerebrospinal Fluid and Parenchymal Brain Development and Growth in the Healthy Fetus. Dev Neurosci 2017; 38:420-429. [PMID: 28315866 DOI: 10.1159/000456711] [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: 08/19/2016] [Accepted: 01/17/2017] [Indexed: 01/26/2023] Open
Abstract
OBJECTIVE The objective of this study was to apply quantitative magnetic resonance imaging to characterize absolute cerebrospinal fluid (CSF) development, as well as its relative development to fetal brain parenchyma in the healthy human fetus. DESIGN We created three-dimensional high-resolution reconstructions of the developing brain for healthy fetuses between 18 and 40 weeks' gestation, segmented the parenchymal and CSF spaces, and calculated the volumes for the lateral, third, and fourth ventricles; extra-axial CSF space; and the cerebrum, cerebellum, and brainstem. From these data, we constructed normograms of the resulting volumes according to gestational age and described the relative development of CSF to fetal brain parenchyma. RESULTS Each CSF space demonstrated major increases in volumetric growth during the second half of gestation: third ventricle (23-fold), extra-axial CSF (11-fold), fourth ventricle (8-fold), and lateral ventricle (2-fold). Total CSF volume was related to total brain volume (p < 0.01), as was lateral ventricle to cerebral volume (p < 0.01); however, the fourth ventricle was not related to cerebellar or brainstem volume (p = 0.18-0.19). RELEVANCE Abnormalities of the CSF spaces are the most common anomalies of neurologic development detected on fetal screening using neurosonography. Normative values of absolute CSF volume, as well as relative growth in comparison to intracranial parenchyma, provide valuable insight into normal fetal neurodevelopment. These data may provide important biomarkers of early deviations from normal growth, better distinguish between benign variants and early disease, and serve as reference standards for postnatal growth and development in the premature infant.
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Deng J, Wang Y. Quantitative magnetic resonance imaging biomarkers in oncological clinical trials: Current techniques and standardization challenges. Chronic Dis Transl Med 2017; 3:8-20. [PMID: 29063052 PMCID: PMC5627686 DOI: 10.1016/j.cdtm.2017.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [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: 12/01/2016] [Indexed: 12/21/2022] Open
Abstract
Radiological imaging plays an important role in oncological trials to provide imaging biomarkers for disease staging, stratifying patients, defining dose setting, and evaluating the safety and efficacy of new candidate drugs and innovative treatment. This paper reviews the techniques of most commonly used quantitative magnetic resonance imaging (qMRI) biomarkers (dynamic contrast enhanced, dynamic susceptibility contrast, and diffusion weighted imaging) and their applications in oncological trials. Challenges of incorporating qMRI biomarkers in oncological trials are discussed including understanding biological mechanisms revealed by MRI biomarkers, consideration of rigorous trial design and standardized implementation of qMRI protocols.
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Affiliation(s)
- Jie Deng
- Department of Medical Imaging, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL 60611, USA.,Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Yi Wang
- Department of Radiology, Peking University People's Hospital, Beijing, 100044, China
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Bidhult S, Kantasis G, Aletras AH, Arheden H, Heiberg E, Hedström E. Validation of T1 and T2 algorithms for quantitative MRI: performance by a vendor-independent software. BMC Med Imaging 2016; 16:46. [PMID: 27501697 PMCID: PMC4977731 DOI: 10.1186/s12880-016-0148-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [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: 12/16/2015] [Accepted: 07/28/2016] [Indexed: 11/26/2022] Open
Abstract
Background Determination of the relaxation time constants T1 and T2 with quantitative magnetic resonance imaging is increasingly used for both research and clinical practice. Recently, groups have been formed within the Society of Cardiovascular Magnetic Resonance to address issues with relaxometry. However, so far they have avoided specific recommendations on methodology due to lack of consensus and current evolving research. Standardised widely available software may simplify this process. The purpose of the current study was to develop and validate vendor-independent T1 and T2 mapping modules and implement those in the versatile and widespread software Segment, freely available for research and FDA approved for clinical applications. Results The T1 and T2 mapping modules were developed and validated in phantoms at 1.5 T and 3 T with reference standard values calculated from reference pulse sequences using the Nelder-Mead Simplex optimisation method. The proposed modules support current commonly available MRI pulse sequences and both 2- and 3-parameter curve fitting. Images acquired in patients using three major vendors showed vendor-independence. Bias and variability showed high agreement with T1 and T2 reference standards for T1 (range 214–1752 ms) and T2 (range 45–338 ms), respectively. Conclusions The developed and validated T1 and T2 mapping and quantification modules generated relaxation maps from current commonly used MRI sequences and multiple signal models. Patient applications showed usability for three major vendors.
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Affiliation(s)
- Sebastian Bidhult
- Department of Clinical Sciences Lund, Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.,Department of Biomedical Engineering, Faculty of Engineering, Lund University, Lund, Sweden
| | - George Kantasis
- Department of Clinical Sciences Lund, Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.,Laboratory of Medical Informatics, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Anthony H Aletras
- Department of Clinical Sciences Lund, Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.,Laboratory of Medical Informatics, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Håkan Arheden
- Department of Clinical Sciences Lund, Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden
| | - Einar Heiberg
- Department of Clinical Sciences Lund, Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden.,Department of Biomedical Engineering, Faculty of Engineering, Lund University, Lund, Sweden
| | - Erik Hedström
- Department of Clinical Sciences Lund, Clinical Physiology, Lund University, Skane University Hospital, Lund, Sweden. .,Department of Clinical Sciences Lund, Diagnostic Radiology, Lund University, Skane University Hospital, Lund, Sweden.
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Gracien RM, Nürnberger L, Hok P, Hof SM, Reitz SC, Rüb U, Steinmetz H, Hilker-Roggendorf R, Klein JC, Deichmann R, Baudrexel S. Evaluation of brain ageing: a quantitative longitudinal MRI study over 7 years. Eur Radiol 2016; 27:1568-1576. [PMID: 27379992 DOI: 10.1007/s00330-016-4485-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [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: 03/24/2016] [Revised: 05/27/2016] [Accepted: 06/21/2016] [Indexed: 12/31/2022]
Abstract
OBJECTIVES T1 relaxometry is a promising tool for the assessment of microstructural changes during brain ageing. Previous cross-sectional studies demonstrated increasing T1 values in white and decreasing T1 values in grey matter over the lifetime. However, these findings have not yet been confirmed on the basis of a longitudinal study. In this longitudinal study over 7 years, T1 relaxometry was used to investigate the dynamics of age-related microstructural changes in older healthy subjects. METHODS T1 mapping was performed in 17 healthy subjects (range 51-77 years) at baseline and after 7 years. Advanced cortical and white matter segmentation was used to determine mean T1 values in the cortex and white matter. RESULTS The analysis revealed a decrease of mean cortical T1 values over 7 years, the rate of T1 reduction being more prominent in subjects with higher age. T1 decreases were predominantly localized in the lateral frontal, parietal and temporal cortex. In contrast, mean white matter T1 values remained stable. CONCLUSIONS T1 mapping is shown to be sensitive to age-related microstructural changes in healthy ageing subjects in a longitudinal setting. Data of a cohort in late adulthood and the senescence period demonstrate a decrease of cortical T1 values over 7 years, most likely reflecting decreasing water content and increased iron concentrations. KEY POINTS • T1 mapping is sensitive to age-related microstructural changes in a longitudinal setting. • T1 decreases were predominantly localized in the lateral frontal, parietal and temporal cortex. • The rate of T1 reduction was more prominent in subjects with higher age. • These changes most likely reflect decreasing cortical water and increasing iron concentrations.
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Affiliation(s)
- René-Maxime Gracien
- Department of Neurology, Goethe University, Frankfurt/Main, Germany. .,Brain Imaging Center, Goethe University, Frankfurt/Main, Germany.
| | - Lucas Nürnberger
- Department of Neurology, Goethe University, Frankfurt/Main, Germany.,Brain Imaging Center, Goethe University, Frankfurt/Main, Germany
| | - Pavel Hok
- Department of Neurology, Goethe University, Frankfurt/Main, Germany.,Brain Imaging Center, Goethe University, Frankfurt/Main, Germany.,Department of Neurology, Palacky University, Olomouc, Czech Republic
| | - Stephanie-Michelle Hof
- Department of Neurology, Goethe University, Frankfurt/Main, Germany.,Brain Imaging Center, Goethe University, Frankfurt/Main, Germany
| | - Sarah C Reitz
- Department of Neurology, Goethe University, Frankfurt/Main, Germany.,Brain Imaging Center, Goethe University, Frankfurt/Main, Germany
| | - Udo Rüb
- Dr. Senckenberg Chronomedical Institute, Goethe University, Frankfurt/Main, Germany
| | | | - Rüdiger Hilker-Roggendorf
- Department of Neurology, Goethe University, Frankfurt/Main, Germany.,Brain Imaging Center, Goethe University, Frankfurt/Main, Germany
| | - Johannes C Klein
- Department of Neurology, Goethe University, Frankfurt/Main, Germany.,Brain Imaging Center, Goethe University, Frankfurt/Main, Germany.,Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Ralf Deichmann
- Brain Imaging Center, Goethe University, Frankfurt/Main, Germany
| | - Simon Baudrexel
- Department of Neurology, Goethe University, Frankfurt/Main, Germany.,Brain Imaging Center, Goethe University, Frankfurt/Main, Germany
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Nilsson M, Lagerstrand K, Kasperska I, Brisby H, Hebelka H. Axial loading during MRI influences T2-mapping values of lumbar discs: a feasibility study on patients with low back pain. Eur Spine J 2016; 25:2856-63. [PMID: 27342614 DOI: 10.1007/s00586-016-4670-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 05/23/2016] [Accepted: 06/18/2016] [Indexed: 01/09/2023]
Abstract
PURPOSE To investigate whether axial loading of the spine during MRI (alMRI) instantaneously induces changes in biochemical disc features as reflected by altered quantitative T2 values in patients with chronic low back pain (LBP). METHODS T2 mapping was performed on 11 LBP patients (54 lumbar discs) during the conventional unloaded MRI and subsequent alMRI. Each disc was divided into five volumetric regions of interests (ROIs), anterior annulus fibrosus (AF) (ROI 1), the interface anterior AF-nucleus pulposus (NP) (ROI 2), NP (ROI 3), the interface NP-posterior AF (ROI 4), and the posterior AF (ROI 5). The mean T2 values for each ROI were compared between MRI and alMRI and correlated with degeneration grade (Pfirrmann), disc angle, and disc level. RESULTS With alMRI, T2 values increased significantly in the whole disc as well as in various parts of the disc with an increase in ROI 1-3 and a decrease in ROI 5. The changes in T2 values correlated to degeneration grade, changes in disc angle, and lumbar level. CONCLUSION alMRI instantaneously induces T2-value changes in lumbar discs and is, thus, a feasible method to reveal dynamic, biochemical disc features in patients with chronic LBP.
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Fosi T, Chu C, Chong WK, Clark C, Scott RC, Boyd S, De Haan M, Neville B. Quantitative magnetic resonance imaging evidence for altered structural remodeling of the temporal lobe in West syndrome. Epilepsia 2015; 56:608-16. [PMID: 25802930 PMCID: PMC5006860 DOI: 10.1111/epi.12907] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [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] [Accepted: 11/30/2014] [Indexed: 12/05/2022]
Abstract
Objective To explore the structure–function relation of the temporal lobe in newly diagnosed West syndrome of unknown cause (uWS). Methods Quantitative magnetic resonance imaging (three‐dimensional [3D] structural MRI and diffusion tensor imaging [DTI]) was analyzed using voxel‐based morphometry (VBM) and tract‐based spatial statistics (TBSS) in 22 patients and healthy age‐matched controls. The electrophysiologic responsiveness of the temporal lobe was measured using the N100 auditory event‐related potential (aERP) to a repeated 1,000 Hz tone. Neurocognitive function was assessed using the Bayley Scales of Infant Development, Second Edition (BSID‐II). Tests followed first‐line treatment with vigabatrin (17 patients) or high‐dose oral prednisolone (5 patients). Results Total temporal lobe volume was similar in patients and controls. Patients had a smaller temporal stem (TS) (p < 0.0001) and planum temporale (PT) (p = 0.029) bilaterally. TS width asymmetry with a larger right‐sided width in controls was absent in patients (p = 0.033). PT asymmetry was present in both groups, being larger on the right (p = 0.048). VBM gray matter volume was increased at the left temporal lobe (superior and middle temporal gyri, the peri‐rhinal cortex, and medial temporal lobe) (p < 0.005, family wise error‐corrected). VBM gray matter volume correlated with the duration of infantile spasms (Pearson's r = −0.630, p = 0.009). DTI metrics did not differ between patients and controls on TBSS. Mean BSID‐II scores were lower (p < 0.001) and auditory N100 ERP attenuated less in patients than in controls (p = 0.002). Significance The functional networking and white matter development of the temporal lobe are impaired following infantile spasms. Treatment may promote structural plasticity within the temporal lobe following infantile spasms, manifest as increased gray matter volume on VBM. It remains to be investigated further whether this predicts patients' long‐term cognitive difficulties.
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Affiliation(s)
- Tangunu Fosi
- Young Epilepsy, Surrey, United Kingdom; Department of Clinical Neurophysiology, Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom; Neurosciences Unit, University College London Institute of Child Health, London, United Kingdom
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Donovan V, Bianchi A, Hartman R, Bhanu B, Carson MJ, Obenaus A. Computational analysis reveals increased blood deposition following repeated mild traumatic brain injury. Neuroimage Clin 2012; 1:18-28. [PMID: 24179733 DOI: 10.1016/j.nicl.2012.08.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 07/12/2012] [Accepted: 08/04/2012] [Indexed: 11/22/2022]
Abstract
Mild traumatic brain injury (mTBI) has become an increasing public health concern as subsequent injuries can exacerbate existing neuropathology and result in neurological deficits. This study investigated the temporal development of cortical lesions using magnetic resonance imaging (MRI) to assess two mTBIs delivered to opposite cortical hemispheres. The controlled cortical impact model was used to produce an initial mTBI on the right cortex followed by a second injury induced on the left cortex at 3 (rmTBI 3d) or 7 (rmTBI 7d) days later. Histogram analysis was combined with a novel semi-automated computational approach to perform a voxel-wise examination of extravascular blood and edema volumes within the lesion. Examination of lesion volume 1d post last injury revealed increased tissue abnormalities within rmTBI 7d animals compared to other groups, particularly at the site of the second impact. Histogram analysis of lesion T2 values suggested increased edematous tissue within the rmTBI 3d group and elevated blood deposition in the rm TBI 7d animals. Further quantification of lesion composition for blood and edema containing voxels supported our histogram findings, with increased edema at the site of second impact in rmTBI 3d animals and elevated blood deposition in the rmTBI 7d group at the site of the first injury. Histological measurements revealed spatial overlap of regions containing blood deposition and microglial activation within the cortices of all animals. In conclusion, our findings suggest that there is a window of tissue vulnerability where a second distant mTBI, induced 7d after an initial injury, exacerbates tissue abnormalities consistent with hemorrhagic progression.
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