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Jun Y, Arefeen Y, Cho J, Fujita S, Wang X, Ellen Grant P, Gagoski B, Jaimes C, Gee MS, Bilgic B. Zero-DeepSub: Zero-shot deep subspace reconstruction for rapid multiparametric quantitative MRI using 3D-QALAS. Magn Reson Med 2024; 91:2459-2482. [PMID: 38282270 PMCID: PMC11005062 DOI: 10.1002/mrm.30018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 12/15/2023] [Accepted: 01/06/2024] [Indexed: 01/30/2024]
Abstract
PURPOSE To develop and evaluate methods for (1) reconstructing 3D-quantification using an interleaved Look-Locker acquisition sequence with T2 preparation pulse (3D-QALAS) time-series images using a low-rank subspace method, which enables accurate and rapid T1 and T2 mapping, and (2) improving the fidelity of subspace QALAS by combining scan-specific deep-learning-based reconstruction and subspace modeling. THEORY AND METHODS A low-rank subspace method for 3D-QALAS (i.e., subspace QALAS) and zero-shot deep-learning subspace method (i.e., Zero-DeepSub) were proposed for rapid and high fidelity T1 and T2 mapping and time-resolved imaging using 3D-QALAS. Using an ISMRM/NIST system phantom, the accuracy and reproducibility of the T1 and T2 maps estimated using the proposed methods were evaluated by comparing them with reference techniques. The reconstruction performance of the proposed subspace QALAS using Zero-DeepSub was evaluated in vivo and compared with conventional QALAS at high reduction factors of up to nine-fold. RESULTS Phantom experiments showed that subspace QALAS had good linearity with respect to the reference methods while reducing biases and improving precision compared to conventional QALAS, especially for T2 maps. Moreover, in vivo results demonstrated that subspace QALAS had better g-factor maps and could reduce voxel blurring, noise, and artifacts compared to conventional QALAS and showed robust performance at up to nine-fold acceleration with Zero-DeepSub, which enabled whole-brain T1, T2, and PD mapping at 1 mm isotropic resolution within 2 min of scan time. CONCLUSION The proposed subspace QALAS along with Zero-DeepSub enabled high fidelity and rapid whole-brain multiparametric quantification and time-resolved imaging.
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Affiliation(s)
- Yohan Jun
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States
- Department of Radiology, Harvard Medical School, Boston, MA, United States
| | - Yamin Arefeen
- Chandra Family Department of Electrical and Computer Engineering, The University of Texas, Austin, TX, United States
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Jaejin Cho
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States
- Department of Radiology, Harvard Medical School, Boston, MA, United States
| | - Shohei Fujita
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States
- Department of Radiology, Harvard Medical School, Boston, MA, United States
| | - Xiaoqing Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States
- Department of Radiology, Harvard Medical School, Boston, MA, United States
| | - P. Ellen Grant
- Department of Radiology, Harvard Medical School, Boston, MA, United States
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, Boston, MA, United States
| | - Borjan Gagoski
- Department of Radiology, Harvard Medical School, Boston, MA, United States
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, Boston, MA, United States
| | - Camilo Jaimes
- Department of Radiology, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Michael S. Gee
- Department of Radiology, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States
| | - Berkin Bilgic
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States
- Department of Radiology, Harvard Medical School, Boston, MA, United States
- Harvard/MIT Health Sciences and Technology, Cambridge, MA, United States
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Chen Y, Meng T, Cao W, Zhang W, Ling J, Wen Z, Qian L, Guo Y, Lin J, Wang H. Histogram analysis of MR quantitative parameters: are they correlated with prognostic factors in prostate cancer? Abdom Radiol (NY) 2024; 49:1534-1544. [PMID: 38546826 DOI: 10.1007/s00261-024-04227-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 01/27/2024] [Accepted: 01/29/2024] [Indexed: 05/22/2024]
Abstract
PURPOSE To investigate the correlation between quantitative MR parameters and prognostic factors in prostate cancer (PCa). METHOD A total of 186 patients with pathologically confirmed PCa who underwent preoperative multiparametric MRI (mpMRI), including synthetic MRI (SyMRI), were enrolled from two medical centers. The histogram metrics of SyMRI [T1, T2, proton density (PD)] and apparent diffusion coefficient (ADC) values were extracted. The Mann‒Whitney U test or Student's t test was employed to determine the association between these histogram features and the prognostically relevant factors. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the differentiation performance. Spearman's rank correlation coefficients were calculated to determine the correlations between histogram parameters and the International Society of Urological Pathology (ISUP) grade group as well as pathological T stage. RESULTS Significant correlations were found between the histogram parameters and the ISUP grade as well as pathological T stage of PCa. Among these histogram parameters, ADC_minimum had the strongest correlation with the ISUP grade (r = - 0.481, p < 0.001), and ADC_Median showed the strongest association with pathological T stage (r = - 0.285, p = 0.008). The ADC_10th percentile exhibited the highest performance in identifying clinically significant prostate cancer (csPCa) (AUC 0.833; 95% CI 0.771-0.883). When discriminating between the status of different prognostically relevant factors, a significant difference was observed between extraprostatic extension-positive and -negative cancers with regard to histogram parameters of the ADC map (10th percentile, 90th percentile, mean, median, minimum) and T1 map (minimum) (p = 0.002-0.032). Moreover, histogram parameters of the ADC map (90th percentile, maximum, mean, median), T2 map (10th percentile, median), and PD map (10th percentile, median) were significantly lower in PCa with perineural invasion (p = 0.009-0.049). The T2 values were significantly lower in patients with seminal vesicle invasion (minimum, p = 0.036) and positive surgical margin (10th percentile, 90th percentile, mean, median, and minimum, p = 0.015-0.025). CONCLUSION Quantitative histogram parameters derived from synthetic MRI and ADC maps may have great potential for predicting the prognostic features of PCa.
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Affiliation(s)
- Yanling Chen
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou, 510080, Guangdong, People's Republic of China
| | - Tiebao Meng
- Department of Radiology, Sun Yat-sen University Cancer Center, No. 651 Dongfeng East Road, Guangzhou, Guangdong, People's Republic of China
| | - Wenxin Cao
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou, 510080, Guangdong, People's Republic of China
| | - Weijing Zhang
- Department of Radiology, Sun Yat-sen University Cancer Center, No. 651 Dongfeng East Road, Guangzhou, Guangdong, People's Republic of China
| | - Jian Ling
- Department of Radiology, The Eastern Hospital of the First Affiliated Hospital, Sun Yat-sen University, No.183 Huangpu Eastern Road, Guangzhou, Guangdong, People's Republic of China
| | - Zhihua Wen
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou, 510080, Guangdong, People's Republic of China
| | - Long Qian
- MR Research, GE Healthcare, Beijing, People's Republic of China
| | - Yan Guo
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou, 510080, Guangdong, People's Republic of China.
| | - Jinhua Lin
- Division of Interventional Ultrasound, Department of Medical Ultrasound, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou, Guangdong, People's Republic of China.
| | - Huanjun Wang
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan 2nd Road, Guangzhou, 510080, Guangdong, People's Republic of China.
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Jacobs L, Mandija S, Liu H, van den Berg CAT, Sbrizzi A, Maspero M. Generalizable synthetic MRI with physics-informed convolutional networks. Med Phys 2024; 51:3348-3359. [PMID: 38063208 DOI: 10.1002/mp.16884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 11/20/2023] [Accepted: 11/28/2023] [Indexed: 05/08/2024] Open
Abstract
BACKGROUND Magnetic resonance imaging (MRI) provides state-of-the-art image quality for neuroimaging, consisting of multiple separately acquired contrasts. Synthetic MRI aims to accelerate examinations by synthesizing any desirable contrast from a single acquisition. PURPOSE We developed a physics-informed deep learning-based method to synthesize multiple brain MRI contrasts from a single 5-min acquisition and investigate its ability to generalize to arbitrary contrasts. METHODS A dataset of 55 subjects acquired with a clinical MRI protocol and a 5-min transient-state sequence was used. The model, based on a generative adversarial network, maps data acquired from the five-minute scan to "effective" quantitative parameter maps (q*-maps), feeding the generated PD, T1, and T2 maps into a signal model to synthesize four clinical contrasts (proton density-weighted, T1-weighted, T2-weighted, and T2-weighted fluid-attenuated inversion recovery), from which losses are computed. The synthetic contrasts are compared to an end-to-end deep learning-based method proposed by literature. The generalizability of the proposed method is investigated for five volunteers by synthesizing three contrasts unseen during training and comparing these to ground truth acquisitions via qualitative assessment and contrast-to-noise ratio (CNR) assessment. RESULTS The physics-informed method matched the quality of the end-to-end method for the four standard contrasts, with structural similarity metrics above0.75 ± 0.08 $0.75\pm 0.08$ ( ± $\pm$ std), peak signal-to-noise ratios above22.4 ± 1.9 $22.4\pm 1.9$ , representing a portion of compact lesions comparable to standard MRI. Additionally, the physics-informed method enabled contrast adjustment, and similar signal contrast and comparable CNRs to the ground truth acquisitions for three sequences unseen during model training. CONCLUSIONS The study demonstrated the feasibility of physics-informed, deep learning-based synthetic MRI to generate high-quality contrasts and generalize to contrasts beyond the training data. This technology has the potential to accelerate neuroimaging protocols.
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Affiliation(s)
- Luuk Jacobs
- Department of Radiotherapy, UMC Utrecht, Utrecht, The Netherlands
- Computational Imaging Group for MR Diagnostics and Therapy, UMC Utrecht, Utrecht, The Netherlands
| | - Stefano Mandija
- Department of Radiotherapy, UMC Utrecht, Utrecht, The Netherlands
- Computational Imaging Group for MR Diagnostics and Therapy, UMC Utrecht, Utrecht, The Netherlands
| | - Hongyan Liu
- Department of Radiotherapy, UMC Utrecht, Utrecht, The Netherlands
- Computational Imaging Group for MR Diagnostics and Therapy, UMC Utrecht, Utrecht, The Netherlands
| | - Cornelis A T van den Berg
- Department of Radiotherapy, UMC Utrecht, Utrecht, The Netherlands
- Computational Imaging Group for MR Diagnostics and Therapy, UMC Utrecht, Utrecht, The Netherlands
| | - Alessandro Sbrizzi
- Department of Radiotherapy, UMC Utrecht, Utrecht, The Netherlands
- Computational Imaging Group for MR Diagnostics and Therapy, UMC Utrecht, Utrecht, The Netherlands
| | - Matteo Maspero
- Department of Radiotherapy, UMC Utrecht, Utrecht, The Netherlands
- Computational Imaging Group for MR Diagnostics and Therapy, UMC Utrecht, Utrecht, The Netherlands
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Ganesh VKSV, Kamepalli HK, Sharma DP, Thomas B, Kesavadas C. Multi-contrast echo-planar imaging sequence (Echo-planar imaging mix) in clinical situations demanding faster MRI-brain scans. J Neurosci Rural Pract 2024; 15:341-348. [PMID: 38746507 PMCID: PMC11090545 DOI: 10.25259/jnrp_508_2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Accepted: 03/10/2024] [Indexed: 05/16/2024] Open
Abstract
Objectives The excellent resolution offered by magnetic resonance imaging (MRI) has a trade-off in the form of scan duration. The purpose of the present study was to assess the clinical utility of echo-planar imaging mix (EPIMix), an echo-planar imaging-based MRI sequence for the brain with a short acquisition time. Materials and Methods This was a retrospective observational study of 50 patients, who could benefit from faster MRI brain scans. The T1, T2, fluid attenuated inversion recovery, diffusion-weighted imaging (DWI), and T2*/susceptibility-weighted imaging sequences were acquired, conventionally and with EPIMix. Conventional and EPIMix images were assessed by two radiologists for overall quality, motion, and susceptibility artifacts and scored on a Likert scale. The scores given for conventional and EPIMix images were compared. The diagnostic performance of EPIMix was also assessed by the ability to detect clinically relevant findings. Results The acquisition time for conventional MRI was 11 min and 45 s and for EPIMix 1 min and 15 s. All EPIMix images were sufficient for diagnostic use. On assessment of the diagnostic performance, it was excellent for ischemic and hemorrhagic strokes. Smaller lesions, lesions adjacent to bone, and post-operative tumors were difficult to identify. Moderate to perfect agreement (Kappa values 0.41-1) was seen between radiologists for all categories except skull base, calvarial, and orbital lesions. Image quality, artifact assessment showed excellent interobserver agreement (>90%) for the scores. All EPIMix images showed reduced motion artifacts. The EPIMix-DWI was comparable to conventional-DWI in terms of quality and artifacts. The remaining sequences showed reduced quality and increased susceptibility. Conclusion The EPIMix has a significantly reduced acquisition time than conventional MRI and could be used instead of conventional MRI in situations demanding faster scans such as suspected acute ischemic or hemorrhagic stroke. In other clinical scenarios, it could help tailor the MRI examination for each patient.
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Affiliation(s)
- Viswanadh Kalaparti Sri Venkata Ganesh
- Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India
| | - Hari Kishore Kamepalli
- Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India
| | | | - Bejoy Thomas
- Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India
| | - Chandrasekharan Kesavadas
- Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India
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Kikuchi K, Togao O, Yamashita K, Isoda T, Nishimura A, Arimura K, Nakamizo A, Yoshimoto K, Ishigami K. Brain volume measured by synthetic magnetic resonance imaging in adult moyamoya disease correlates with cerebral blood flow and brain function. Sci Rep 2024; 14:5468. [PMID: 38443400 PMCID: PMC10914740 DOI: 10.1038/s41598-024-56210-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 03/04/2024] [Indexed: 03/07/2024] Open
Abstract
Moyamoya disease (MMD) is characterized by progressive arterial occlusion, causing chronic hemodynamic impairment, which can reduce brain volume. A novel quantitative technique, synthetic magnetic resonance imaging (SyMRI), can evaluate brain volume. This study aimed to investigate whether brain volume measured with SyMRI correlated with cerebral blood flow (CBF) and brain function in adult MMD. In this retrospective study, 18 adult patients with MMD were included. CBF was measured using iodine-123-N-isopropyl-p-iodoamphetamine single photon emission computed tomography. Cerebrovascular reactivity (CVR) to acetazolamide challenge was also evaluated. Brain function was measured using the Wechsler Adult Intelligence Scales (WAIS)-III/IV and the WAIS-R tests. Gray matter (GM), white matter, and myelin-correlated volumes were evaluated in six areas. Resting CBF was positively correlated with GM fractions in the right anterior cerebral arterial and right middle cerebral arterial (MCA) territories. CVR was positively correlated with GM fraction in the right posterior cerebral arterial (PCA) territory. Full-Scale Intelligence Quotient and Verbal Comprehension Index scores were marginally positively correlated with GM fractions in the left PCA territory. Processing Speed Index score was marginally positively correlated with GM fraction in the right MCA territory. The SyMRI-measured territorial GM fraction correlated with CBF and brain function in patients with MMD.
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Affiliation(s)
- Kazufumi Kikuchi
- Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
| | - Osamu Togao
- Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Koji Yamashita
- Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Takuro Isoda
- Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Ataru Nishimura
- Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Koichi Arimura
- Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Akira Nakamizo
- Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Koji Yoshimoto
- Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Kousei Ishigami
- Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
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Estler A, Hauser TK, Mengel A, Brunnée M, Zerweck L, Richter V, Zuena M, Schuhholz M, Ernemann U, Gohla G. Deep Learning Accelerated Image Reconstruction of Fluid-Attenuated Inversion Recovery Sequence in Brain Imaging: Reduction of Acquisition Time and Improvement of Image Quality. Acad Radiol 2024; 31:180-186. [PMID: 37280126 DOI: 10.1016/j.acra.2023.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/08/2023] [Accepted: 05/08/2023] [Indexed: 06/08/2023]
Abstract
RATIONALE AND OBJECTIVES Fluid-attenuated inversion recovery (FLAIR) imaging is playing an increasingly significant role in the detection of brain metastases with a concomitant increase in the number of magnetic resonance imaging (MRI) examinations. Therefore, the purpose of this study was to investigate the impact on image quality and diagnostic confidence of an innovative deep learning-based accelerated FLAIR (FLAIRDLR) sequence of the brain compared to conventional (standard) FLAIR (FLAIRS) imaging. MATERIALS AND METHODS Seventy consecutive patients with staging cerebral MRIs were retrospectively enrolled in this single-center study. The FLAIRDLR was conducted using the same MRI acquisition parameters as the FLAIRS sequence, except for a higher acceleration factor for parallel imaging (from 2 to 4), which resulted in a shorter acquisition time of 1:39 minute instead of 2:40 minutes (-38%). Two specialized neuroradiologists evaluated the imaging datasets using a Likert scale that ranged from 1 to 4, with 4 indicating the best score for the following parameters: sharpness, lesion demarcation, artifacts, overall image quality, and diagnostic confidence. Additionally, the image preference of the readers and the interreader agreement were assessed. RESULTS The average age of the patients was 63 ± 11years. FLAIRDLR exhibited significantly less image noise than FLAIRS, with P-values of< .001 and< .05, respectively. The sharpness of the images and the ability to detect lesions were rated higher in FLAIRDLR, with a median score of 4 compared to a median score of 3 in FLAIRS (P-values of<.001 for both readers). In terms of overall image quality, FLAIRDLR was rated superior to FLAIRS, with a median score of 4 vs 3 (P-values of<.001 for both readers). Both readers preferred FLAIRDLR in 68/70 cases. CONCLUSION The feasibility of deep learning FLAIR brain imaging was shown with additional 38% reduction in examination time compared to standard FLAIR imaging. Furthermore, this technique has shown improvement in image quality, noise reduction, and lesion demarcation.
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Affiliation(s)
- Arne Estler
- Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tübingen, Baden-Württemberg, Germany (A.E., T.-K.H., L.Z., V.R., M.Z., U.E., G.G.).
| | - Till-Karsten Hauser
- Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tübingen, Baden-Württemberg, Germany (A.E., T.-K.H., L.Z., V.R., M.Z., U.E., G.G.)
| | - Annerose Mengel
- Department of Neurology & Stroke, Eberhard-Karls University of Tübingen, Tuebingen, Germany (A.M.)
| | - Merle Brunnée
- Department of Neuroradiology, Neurological University Clinic, Heidelberg University Hospital, Heidelberg, Germany (M.B.)
| | - Leonie Zerweck
- Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tübingen, Baden-Württemberg, Germany (A.E., T.-K.H., L.Z., V.R., M.Z., U.E., G.G.)
| | - Vivien Richter
- Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tübingen, Baden-Württemberg, Germany (A.E., T.-K.H., L.Z., V.R., M.Z., U.E., G.G.)
| | - Mario Zuena
- Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tübingen, Baden-Württemberg, Germany (A.E., T.-K.H., L.Z., V.R., M.Z., U.E., G.G.)
| | - Martin Schuhholz
- Faculty of Medicine, University of Tuebingen, Tübingen, Germany (M.S.)
| | - Ulrike Ernemann
- Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tübingen, Baden-Württemberg, Germany (A.E., T.-K.H., L.Z., V.R., M.Z., U.E., G.G.)
| | - Georg Gohla
- Diagnostic and Interventional Neuroradiology, Department of Radiology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tübingen, Baden-Württemberg, Germany (A.E., T.-K.H., L.Z., V.R., M.Z., U.E., G.G.)
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Fukunaga K, Fujiwara Y, Enzaki M, Komi M, Hirai T, Azuma M. [Usefulness of Voxel-Based Quantification (VBQ) Smoothing in Relaxation Time Mapping]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2023; 79:913-922. [PMID: 37544734 DOI: 10.6009/jjrt.2023-1378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
PURPOSE Voxel-based quantification (VBQ) smoothing is a technique used to smooth quantitative parametric maps in the Montreal Neurological Institute standard space. Although VBQ smoothing could suppress changes in quantitative values at tissue boundaries, its effectiveness on relaxation time (T1 and T2 values and proton density PD) maps has not been investigated. The purpose of this study was to clarify the usefulness of VBQ smoothing in relaxation time mapping. METHOD T1 and T2 values and PD maps of the brains of 20 healthy participants were obtained using a two-dimensional multi-dynamic multi-echo sequence. VBQ and Gaussian smoothing were applied to the relaxation time maps by varying the kernel size by 1 mm from 1 to 6 mm. Changes in relaxation time before and after VBQ and Gaussian smoothing for the putamen, caudate nucleus, substantia nigra, and corpus callosum on the relaxation time maps were evaluated. RESULT The changes in relaxation time after VBQ smoothing application were smaller than those in that after Gaussian smoothing application. Although the differences in the relaxation time for all tissues before and after VBQ and Gaussian smoothing applications increased with increasing kernel size for all relaxation times for both methods, the changes in the relaxation time for VBQ smoothing were smaller than those in that for Gaussian smoothing. CONCLUSION VBQ smoothing can suppress the change in the relaxation time on the boundary of the tissue and is thus a useful smoothing technique in relaxation time mapping.
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Affiliation(s)
- Kota Fukunaga
- Graduate School of Health Sciences, Kumamoto University
| | - Yasuhiro Fujiwara
- Department of Medical Image Sciences, Faculty of Life Sciences, Kumamoto University
| | | | | | - Toshinori Hirai
- Department of Diagnostic Radiology, Faculty of Medicine, Kumamoto University
| | - Minako Azuma
- Department of Radiology, Faculty of Medicine, University of Miyazaki
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Donatelli G, Cecchi P, Migaleddu G, Cencini M, Frumento P, D'Amelio C, Peretti L, Buonincontri G, Pasquali L, Tosetti M, Cosottini M, Costagli M. Quantitative T1 mapping detects blood-brain barrier breakdown in apparently non-enhancing multiple sclerosis lesions. Neuroimage Clin 2023; 40:103509. [PMID: 37717382 PMCID: PMC10514220 DOI: 10.1016/j.nicl.2023.103509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 08/09/2023] [Accepted: 09/10/2023] [Indexed: 09/19/2023]
Abstract
OBJECTIVES The disruption of the blood-brain barrier (BBB) is a key and early feature in the pathogenesis of demyelinating multiple sclerosis (MS) lesions and has been neuropathologically demonstrated in both active and chronic plaques. The local overt BBB disruption in acute demyelinating lesions is captured as signal hyperintensity in post-contrast T1-weighted images because of the contrast-related shortening of the T1 relaxation time. On the contrary, the subtle BBB disruption in chronic lesions is not visible at conventional radiological evaluation but it might be of clinical relevance. Indeed, persistent, subtle BBB leakage might be linked to low-grade inflammation and plaque evolution. Here we hypothesised that 3D Quantitative Transient-state Imaging (QTI) was able to reveal and measure T1 shortening (ΔT1) reflecting small amounts of contrast media leakage in apparently non-enhancing lesions (ANELs). MATERIALS AND METHODS Thirty-four patients with relapsing remitting MS were included in the study. All patients underwent a 3 T MRI exam of the brain including conventional sequences and QTI acquisitions (1.1 mm isotropic voxel) performed both before and after contrast media administration. For each patient, a ΔT1 map was obtained via voxel-wise subtraction of pre- and post- contrast QTI-derived T1 maps. ΔT1 values measured in ANELs were compared with those recorded in enhancing lesions and in the normal appearing white matter. A reference distribution of ΔT1 in the white matter was obtained from datasets acquired in 10 non-MS patients with unrevealing MR imaging. RESULTS Mean ΔT1 in ANELs (57.45 ± 48.27 ms) was significantly lower than in enhancing lesions (297.71 ± 177.52 ms; p < 0. 0001) and higher than in the normal appearing white matter (36.57 ± 10.53 ms; p < 0.005). Fifty-two percent of ANELs exhibited ΔT1 higher than those observed in the white matter of non-MS patients. CONCLUSIONS QTI-derived quantitative ΔT1 mapping enabled to measure contrast-related T1 shortening in ANELs. ANELs exhibiting ΔT1 values that deviate from the reference distribution in non-MS patients may indicate persistent, subtle, BBB disruption. Access to this information may be proved useful to better characterise pathology and objectively monitor disease activity and response to therapy.
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Affiliation(s)
- Graziella Donatelli
- Neuroradiology Unit, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy; Imago7 Research Foundation, Pisa, Italy
| | - Paolo Cecchi
- Neuroradiology Unit, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy; Imago7 Research Foundation, Pisa, Italy
| | | | - Matteo Cencini
- National Institute for Nuclear Physics (INFN), Pisa Division, Pisa, Italy
| | - Paolo Frumento
- Department of Political Sciences, University of Pisa, Pisa, Italy
| | - Claudio D'Amelio
- Neuroradiology Unit, Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Luca Peretti
- Imago7 Research Foundation, Pisa, Italy; Laboratory of Medical Physics and Magnetic Resonance, IRCCS Stella Maris, Pisa, Italy
| | - Guido Buonincontri
- Laboratory of Medical Physics and Magnetic Resonance, IRCCS Stella Maris, Pisa, Italy
| | - Livia Pasquali
- Neurology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Michela Tosetti
- Laboratory of Medical Physics and Magnetic Resonance, IRCCS Stella Maris, Pisa, Italy
| | - Mirco Cosottini
- Neuroradiology Unit, Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
| | - Mauro Costagli
- Laboratory of Medical Physics and Magnetic Resonance, IRCCS Stella Maris, Pisa, Italy; Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Sciences (DINOGMI), University of Genoa, Genoa, Italy
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Peretti L, Donatelli G, Cencini M, Cecchi P, Buonincontri G, Cosottini M, Tosetti M, Costagli M. Generating Synthetic Radiological Images with PySynthMRI: An Open-Source Cross-Platform Tool. Tomography 2023; 9:1723-1733. [PMID: 37736990 PMCID: PMC10514862 DOI: 10.3390/tomography9050137] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/07/2023] [Accepted: 09/08/2023] [Indexed: 09/23/2023] Open
Abstract
Synthetic MR Imaging allows for the reconstruction of different image contrasts from a single acquisition, reducing scan times. Commercial products that implement synthetic MRI are used in research. They rely on vendor-specific acquisitions and do not include the possibility of using custom multiparametric imaging techniques. We introduce PySynthMRI, an open-source tool with a user-friendly interface that uses a set of input images to generate synthetic images with diverse radiological contrasts by varying representative parameters of the desired target sequence, including the echo time, repetition time and inversion time(s). PySynthMRI is written in Python 3.6, and it can be executed under Linux, Windows, or MacOS as a python script or an executable. The tool is free and open source and is developed while taking into consideration the possibility of software customization by the end user. PySynthMRI generates synthetic images by calculating the pixelwise signal intensity as a function of a set of input images (e.g., T1 and T2 maps) and simulated scanner parameters chosen by the user via a graphical interface. The distribution provides a set of default synthetic contrasts, including T1w gradient echo, T2w spin echo, FLAIR and Double Inversion Recovery. The synthetic images can be exported in DICOM or NiFTI format. PySynthMRI allows for the fast synthetization of differently weighted MR images based on quantitative maps. Specialists can use the provided signal models to retrospectively generate contrasts and add custom ones. The modular architecture of the tool can be exploited to add new features without impacting the codebase.
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Affiliation(s)
- Luca Peretti
- Laboratory of Medical Physics and Magnetic Resonance, IRCCS Stella Maris, 56128 Pisa, Italy; (L.P.)
- Imago 7 Research Foundation, 56128 Pisa, Italy
- Department of Computer Science, University of Pisa, 56127 Pisa, Italy
| | - Graziella Donatelli
- Imago 7 Research Foundation, 56128 Pisa, Italy
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Azienda Ospedaliero-Universitaria Pisana, 56124 Pisa, Italy
| | - Matteo Cencini
- Italian National Institute of Nuclear Physics (INFN), Section of Pisa, 56127 Pisa, Italy
| | - Paolo Cecchi
- Imago 7 Research Foundation, 56128 Pisa, Italy
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy
| | - Guido Buonincontri
- Laboratory of Medical Physics and Magnetic Resonance, IRCCS Stella Maris, 56128 Pisa, Italy; (L.P.)
| | - Mirco Cosottini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy
| | - Michela Tosetti
- Laboratory of Medical Physics and Magnetic Resonance, IRCCS Stella Maris, 56128 Pisa, Italy; (L.P.)
| | - Mauro Costagli
- Laboratory of Medical Physics and Magnetic Resonance, IRCCS Stella Maris, 56128 Pisa, Italy; (L.P.)
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Sciences (DINOGMI), University of Genoa, 16132 Genoa, Italy
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Nasser NS, Sharma K, Mehta PM, Mahajan V, Mahajan H, Venugopal VK. Estimation of white matter hyperintensities with synthetic MRI myelin volume fraction in patients with multiple sclerosis and non-multiple-sclerosis white matter hyperintensities: A pilot study among the Indian population. AIMS Neurosci 2023; 10:144-153. [PMID: 37426773 PMCID: PMC10323258 DOI: 10.3934/neuroscience.2023011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 05/03/2023] [Accepted: 05/09/2023] [Indexed: 07/11/2023] Open
Abstract
AIM Synthetic MRI (SyMRI) works on the MDME sequence, which acquires the relaxation properties of the brain and helps to measure the accurate tissue properties in 6 minutes. The aim of this study was to evaluate the synthetic MRI (SyMRI)-generated myelin (MyC) to white matter (WM) ratio, the WM fraction (WMF), MyC partial maps performing normative brain volumetry to investigate MyC loss in multiple sclerosis (MS) patients with white-matter hyperintensites (WMHs) and non-MS patients with WMHs in a clinical setting. MATERIALS and METHODS Synthetic MRI images were acquired from 15 patients with MS, and from 15 non-MS patients on a 3T MRI scanner (Discovery MR750w; GE Healthcare; Milwaukee, USA) using MAGiC, a customized version of SyntheticMR's SyMRI® IMAGE software marketed by GE Healthcare under a license agreement. Fast multi-delay multi-echo acquisition was performed with a 2D axial pulse sequence with different combinations of echo time (TEs) and saturation delay times. The total image acquisition time was 6 minutes. SyMRI image analysis was done using SyMRI software (SyMRI Version: 11.3.6; Synthetic MR, Linköping, Sweden). SyMRI data were used to generate the MyC partial maps and WMFs to quantify the signal intensities of test group and control group, andcontrol group , and their mean values were recorded. All patients also underwent conventional diffusion-weighted imaging, i.e., T1w and T2w imaging. RESULTS The results showed that the WMF was significantly lower in the test group than in the control group (38.8% vs 33.2%, p < 0.001). The Mann-Whitney U nonparametric t-test revealed a significant difference in the mean myelin volume between the test group and the control group (158.66 ± 32.31 vs. 138.29 ± 29.28, p = 0.044). Also, there were no significant differences in the gray matter fraction and intracranial volume between the test group and the control group. CONCLUSIONS We observed MyC loss in test group using quantitative SyMRI. Thus, myelin loss in MS patients can be quantitatively evaluated using SyMRI.
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Fukunaga K, Enzaki M, Komi M, Azuma M, Hirai T, Fujiwara Y. [Evaluation of the Accuracy of Relaxation Time Measurements Using 3D-QALAS at 3.0 T MRI and Comparison with 2D-MDME]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2023:2023-1343. [PMID: 37211403 DOI: 10.6009/jjrt.2023-1343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
PURPOSE Three-dimensional (3D) quantification using an interleaved Look-Locker acquisition sequence with a T2 preparation pulse (QALAS) is a quantitative sequence used to measure relaxation times. The accuracy of the relaxation time measurement of 3D-QALAS at 3.0 T and the bias of 3D-QALAS have not yet been assessed. The purpose of this study was to clarify the accuracy of the relaxation time measurements using 3D-QALAS at 3.0 T MRI. METHODS The accuracy of the T1 and T2 values for 3D-QALAS was evaluated using a phantom. Subsequently, the T1 and T2 values and proton density of the brain parenchyma in healthy subjects were measured using 3D-QALAS and compared with those of 2D multi-dynamic multi-echo (MDME). RESULTS In the phantom study, the average T1 value of 3D-QALAS was 8.3% prolonged than that for conventional inversion recovery spin-echo; the average T2 value for 3D-QALAS was 18.4% shorter than that for multi-echo spin-echo. The in vivo assessment showed that the mean T1 and T2 values and PD for 3D-QALAS were prolonged by 5.3%, shortened by 9.6%, and increased by 7.0%, respectively, compared with those for 2D-MDME. CONCLUSION Although 3D-QALAS at 3.0 T has high accuracy T1 value, which is less than 1000 ms, the T1 value could be overestimated for tissues with it longer than that T1 value. The T2 value for 3D-QALAS could be underestimated for tissues with T2 values, and this tendency increases with longer T2 values.
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Affiliation(s)
- Kota Fukunaga
- Graduate School of Health Sciences, Kumamoto University
| | | | | | - Minako Azuma
- Department of Radiology, Faculty of Medicine, University of Miyazaki
| | - Toshinori Hirai
- Department of Diagnostic Radiology, Faculty of Medicine, Kumamoto University
| | - Yasuhiro Fujiwara
- Department of Medical Image Sciences, Faculty of Life Sciences, Kumamoto University
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12
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Zou M, Zhou Q, Li R, Hu M, Qian L, Yang Z, Zhao J. Image quality using synthetic brain MRI: an age-stratified study. Acta Radiol 2023; 64:2010-2023. [PMID: 36775871 DOI: 10.1177/02841851231152098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
BACKGROUND Synthetic magnetic resonance imaging (MRI) might replace the conventional MR sequences in brain evaluation to shorten scan time and obtain multiple quantitative parameters. PURPOSE To evaluate the image quality of multiple-delay-multiple-echo (MDME) sequence-derived synthetic brain MR images compared to conventional images by considering a multi-age sample. MATERIAL AND METHODS Image sets of conventional and synthetic MRI of 200 participants were included. On the basis of the presence of intracranial lesions, the participants were divided into a normal group and a pathological group. Two neuroradiologists compared the anonymous and unordered images. Image quality, artifacts, and diagnostic performance were analyzed. RESULTS In the quantitative analysis, comparing with conventional images, MDME sequence-derived synthetic MRI demonstrated an equal/greater signal-to-noise ratio and contrast-to-noise ratio (CNR) in all age groups. Specifically, for participants aged ≤2 years, synthetic T2-fluid-attenuated inversion recovery imaging showed a significantly higher cerebellum gray/white matter CNR (P < 0.05). In the qualitative and artifact analyses, except for the superior sagittal sinus and cranial nerves, synthetic MRI showed good imaging quality (≥3 points) in all brain structures. On synthetic T1-weighted imaging, high signal intensity within the superior sagittal sinus was found in most of our participants (107/118, 90.7%). No difference was observed between synthetic and conventional MRI in diagnosing the lesions. CONCLUSION MDME sequence-derived synthetic MRI showed similar image quality and diagnostic performance with a shorter acquisition time than conventional MRI. However, the high signal intensity within the superior sagittal sinus on synthetic T1-weighted images requires consideration.
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Affiliation(s)
- Mengsha Zou
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Qin Zhou
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Ruocheng Li
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Manshi Hu
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Long Qian
- MR Research, GE Healthcare, Beijing, PR China
| | - Zhiyun Yang
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Jing Zhao
- Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, PR China
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Nabavizadeh A, Barkovich MJ, Mian A, Ngo V, Kazerooni AF, Villanueva-Meyer JE. Current state of pediatric neuro-oncology imaging, challenges and future directions. Neoplasia 2023; 37:100886. [PMID: 36774835 PMCID: PMC9945752 DOI: 10.1016/j.neo.2023.100886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 01/20/2023] [Accepted: 02/05/2023] [Indexed: 02/12/2023]
Abstract
Imaging plays a central role in neuro-oncology including primary diagnosis, treatment planning, and surveillance of tumors. The emergence of quantitative imaging and radiomics provided an uprecedented opportunity to compile mineable databases that can be utilized in a variety of applications. In this review, we aim to summarize the current state of conventional and advanced imaging techniques, standardization efforts, fast protocols, contrast and sedation in pediatric neuro-oncologic imaging, radiomics-radiogenomics, multi-omics and molecular imaging approaches. We will also address the existing challenges and discuss future directions.
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Affiliation(s)
- Ali Nabavizadeh
- Department of Radiology, Hospital of University of Pennsylvania, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Center for Data-Driven Discovery in Biomedicine (D3b), Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
| | - Matthew J Barkovich
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Ali Mian
- Division of Neuroradiology, Mallinckrodt Institute of Radiology, Washington University in St. Louis, Missouri, USA
| | - Van Ngo
- Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Anahita Fathi Kazerooni
- Center for Data-Driven Discovery in Biomedicine (D3b), Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Javier E Villanueva-Meyer
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
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14
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Fujiwara Y. [19. Basic Principle and Clinical Application of Synthetic MRI]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2023; 79:851-856. [PMID: 37599070 DOI: 10.6009/jjrt.2023-2243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/22/2023]
Affiliation(s)
- Yasuhiro Fujiwara
- Department of Medical Image Sciences, Faculty of Life Sciences, Kumamoto University
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Tissue Characteristics of Endometrial Carcinoma Analyzed by Quantitative Synthetic MRI and Diffusion-Weighted Imaging. Diagnostics (Basel) 2022; 12:diagnostics12122956. [PMID: 36552962 PMCID: PMC9776551 DOI: 10.3390/diagnostics12122956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/08/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND This study investigates the association of T1, T2, proton density (PD) and the apparent diffusion coefficient (ADC) with histopathologic features of endometrial carcinoma (EC). METHODS One hundred and nine EC patients were prospectively enrolled from August 2019 to December 2020. Synthetic magnetic resonance imaging (MRI) was acquired through one acquisition, in addition to diffusion-weighted imaging (DWI) and other conventional sequences using 1.5T MRI. T1, T2, PD derived from synthetic MRI and ADC derived from DWI were compared among different histopathologic features, namely the depth of myometrial invasion (MI), tumor grade, cervical stromal invasion (CSI) and lymphovascular invasion (LVSI) of EC by the Mann-Whitney U test. Classification models based on the significant MRI metrics were constructed with their respective receiver operating characteristic (ROC) curves, and their micro-averaged ROC was used to evaluate the overall performance of these significant MRI metrics in determining aggressive histopathologic features of EC. RESULTS EC with MI had significantly lower T2, PD and ADC than those without MI (p = 0.007, 0.006 and 0.043, respectively). Grade 2-3 EC and EC with LVSI had significantly lower ADC than grade 1 EC and EC without LVSI, respectively (p = 0.005, p = 0.020). There were no differences in the MRI metrics in EC with or without CSI. Micro-averaged ROC of the three models had an area under the curve of 0.83. CONCLUSIONS Synthetic MRI provided quantitative metrics to characterize EC with one single acquisition. Low T2, PD and ADC were associated with aggressive histopathologic features of EC, offering excellent performance in determining aggressive histopathologic features of EC.
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Time-saving synthetic magnetic resonance imaging protocols for pediatric neuroimaging: impact of echo train length and bandwidth on image quality. Pediatr Radiol 2022; 52:2401-2412. [PMID: 35661908 DOI: 10.1007/s00247-022-05389-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/01/2022] [Accepted: 04/26/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Synthetic MRI is a time-efficient imaging technique that provides both quantitative MRI and contrast-weighted images simultaneously. However, a rather long single scan time can be challenging for children. OBJECTIVE To evaluate the clinical feasibility of time-saving synthetic MRI protocols adjusted for echo train length and receiver bandwidth in pediatric neuroimaging based on image quality assessment and quantitative data analysis. MATERIALS AND METHODS In total, we included 33 children ages 1.6-17.4 years who underwent synthetic MRI using three sets of echo train length and receiver bandwidth combinations (echo train length [E]12-bandwidth [B in KHz]22, E16-B22 and E16-B83) at 3 T. The image quality and lesion conspicuity of synthetic contrast-weighted images were compared between the suggested protocol (E12-B22) and adjusted protocols (E16-B22 and E16-B83). We also compared tissue values (T1, T2, proton-density values) and brain volumetry. RESULTS For the E16-B83 combination, image quality was sufficient except for 15.2% of T1-W and 3% of T2-W fluid-attenuated inversion recovery (FLAIR) images, with remarkable scan time reduction (up to 35%). The E16-B22 combination demonstrated a comparable image quality to E12-B22 (P>0.05) with a scan time reduction of up to 8%. There were no significant differences in lesion conspicuity among the three protocols (P>0.05). Tissue value measurements and brain tissue volumes obtained with the E12-B22 protocol and adjusted protocols showed excellent agreement and strong correlations except for gray matter volume and non-white matter/gray matter/cerebrospinal fluid volume in E12-B22 vs. E16-B83. CONCLUSION The adjusted synthetic protocols produced image quality sufficient or comparable to that of the suggested protocol while maintaining lesion conspicuity with reduced scan time. The quantitative values were generally consistent with the suggested MRI-protocol-derived values, which supports the clinical application of adjusted protocols in pediatric neuroimaging.
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17
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Synthetic double inversion recovery imaging in brain MRI: quantitative evaluation and feasibility of synthetic MRI and a comparison with conventional double inversion recovery and fluid-attenuated inversion recovery sequences. BMC Med Imaging 2022; 22:183. [PMID: 36303114 PMCID: PMC9615305 DOI: 10.1186/s12880-022-00877-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/16/2022] [Indexed: 11/17/2022] Open
Abstract
Background and purpose Synthetic MR imaging (SyMRI) allows the reconstruction of various contrast images, including double inversion recovery (DIR), from a single scan. This study aimed to investigate the advantages of SyMRI by comparing synthetic DIR images with synthetic T2-weighted fluid-attenuated inversion recovery (T2W-FLAIR) and conventional DIR images. Materials and methods We retrospectively reviewed the imaging data of 100 consecutive patients who underwent brain MRI between December 2018 and March 2019. Synthetic DIR, T2W-FLAIR, T1-weighted, and phase-sensitive inversion recovery (PSIR) images were generated from SyMRI data. For synthetic DIR, the two inversion times required to suppress white matter and cerebrospinal fluid (CSF) were manually determined by two radiologists. Quantitative analysis was performed by manually tracing the region of interest (ROI) at the sites of the lesion, white matter, and CSF. Synthetic DIR, synthetic T2W-FLAIR, and conventional DIR images were compared on the basis of using the gray matter-to-white matter, lesion-to-white matter, and lesion-to-CSF contrast-to-noise ratios. Results The two radiologists showed no differences in setting inversion time (TI) values, and their evaluations showed excellent interobserver agreement. The mean signal intensities obtained with synthetic DIR were significantly higher than those obtained with synthetic T2W-FLAIR and conventional DIR. Conclusion Synthetic DIR images showed a higher contrast than synthetic T2WFLAIR and conventional DIR images. Supplementary Information The online version contains supplementary material available at 10.1186/s12880-022-00877-4.
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Response to the letter synthetic double inversion recovery (DIR) and phase-sensitive inversion recovery (PSIR) images showed better delineation of multiple sclerosis plaques. Neuroradiology 2022; 64:1915-1916. [PMID: 36066632 DOI: 10.1007/s00234-022-03040-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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19
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Improving Image Quality and Reducing Scan Time for Synthetic MRI of Breast by Using Deep Learning Reconstruction. BIOMED RESEARCH INTERNATIONAL 2022; 2022:3125426. [PMID: 36060133 PMCID: PMC9439918 DOI: 10.1155/2022/3125426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 07/20/2022] [Accepted: 07/26/2022] [Indexed: 11/17/2022]
Abstract
Objectives. To investigate a deep learning reconstruction algorithm to reduce the time of synthetic MRI (SynMRI) scanning on the breast and improve the image quality. Materials and Methods. A total of 192 healthy female volunteers (mean age: 48.1 years) underwent the breast MR examination at 3.0 T from September 2020 to June 2021. Standard SynMRI and fast SynMRI scans were collected simultaneously on the same volunteer. Deep learning technology with a generative adversarial network (GAN) was used to generate high-quality fast SynMRI images by end-to-end training. Peak signal-to-noise ratio (PSNR), mean squared error (MSE), and structural similarity index measure (SSIM) were used to compare the image quality of generated images from fast SynMRI by deep learning algorithms. Results. Fast SynMRI acquisition time is half of the standard SynMRI scan, and the generated images of the GAN model show that PSNR and SSIM are improved and MSE is reduced. Conclusion. The application of deep learning algorithms with GAN model in breast MAGiC MRI improves the image quality and reduces the scanning time.
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Nakaya M, Hagiwara A, Hori M, Yokoyama K, Fujita S, Andica C, Kamagata K, Hoshino Y, Tomizawa Y, Hattori N, Aoki S. Synthetic double inversion recovery (DIR) and phase-sensitive inversion recovery (PSIR) images showed better delineation of multiple sclerosis plaques. Neuroradiology 2022; 64:1913-1914. [PMID: 35927362 DOI: 10.1007/s00234-022-03031-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 07/28/2022] [Indexed: 10/16/2022]
Affiliation(s)
- Moto Nakaya
- Department of Radiology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.,Department of Radiology, Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Akifumi Hagiwara
- Department of Radiology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan. .,Department of Radiology, Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
| | - Masaaki Hori
- Department of Radiology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.,Department of Radiology, Toho University Omori Medical Center, 6-11-1 Omorinishi, Ota-ku, Tokyo, 143-8541, Japan
| | - Kazumasa Yokoyama
- Department of Neurology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Shohei Fujita
- Department of Radiology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.,Department of Radiology, Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Christina Andica
- Department of Radiology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.,Faculty of Health Data Science, Juntendo University, 2- 5-1, Takasu, Urayasu, Chiba, 279-0013, Japan
| | - Koji Kamagata
- Department of Radiology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Yasunobu Hoshino
- Department of Neurology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Yuji Tomizawa
- Department of Neurology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Nobutaka Hattori
- Department of Neurology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Shigeki Aoki
- Department of Radiology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
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André J, Barrit S, Jissendi P. Synthetic MRI for stroke: a qualitative and quantitative pilot study. Sci Rep 2022; 12:11552. [PMID: 35798771 PMCID: PMC9262877 DOI: 10.1038/s41598-022-15204-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 06/20/2022] [Indexed: 11/09/2022] Open
Abstract
Synthetic MR provides qualitative and quantitative multi-parametric data about tissue properties in a single acquisition. Its use in stroke imaging is not yet established. We compared synthetic and conventional image quality and studied synthetic relaxometry of acute and chronic ischemic lesions to investigate its interest for stroke imaging. We prospectively acquired synthetic and conventional brain MR of 43 consecutive adult patients with suspected stroke. We studied a total of 136 lesions, of which 46 DWI-positive with restricted ADC (DWI + /rADC), 90 white matter T2/FLAIR hyperintensities (WMH) showing no diffusion restriction, and 430 normal brain regions (NBR). We assessed image quality for lesion definition according to a 3-level score by two readers of different experiences. We compared relaxometry of lesions and regions of interest. Synthetic images were superior to their paired conventional images for lesion definition except for sFLAIR (sT1 or sPSIR vs. cT1 and sT2 vs. cT2 for DWI + /rADC and WMH definition; p values < .001) with substantial to almost perfect inter-rater reliability (κ ranging from 0.711 to 0.932, p values < .001). We found significant differences in relaxometry between lesions and NBR and between acute and chronic lesions (T1, T2, and PD of DWI + /rADC or WMH vs. mirror NBR; p values < .001; T1 and PD of DWI + /rADC vs. WMH; p values of 0.034 and 0.008). Synthetic MR may contribute to stroke imaging by fast generating accessible weighted images for visual inspection derived from rapidly acquired relaxometry data. Moreover, this synthetic relaxometry could differentiate acute and chronic ischemic lesions.
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Affiliation(s)
- Joachim André
- Department of Radiology, Hôpital Erasme, Université Libre de Bruxelles (ULB), Route de Lennik, 808, 1070, Anderlecht, Brussels, Belgium.
| | - Sami Barrit
- Department of Neurosurgery, Hôpital Erasme, Université Libre de Bruxelles (ULB), Brussels, Belgium
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22
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Assessment of 2D conventional and synthetic MRI in multiple sclerosis. Neuroradiology 2022; 64:2315-2322. [PMID: 35583667 DOI: 10.1007/s00234-022-02973-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 05/02/2022] [Indexed: 12/23/2022]
Abstract
PURPOSE To qualitatively and quantitatively compare synthetic and conventional MRI sequences acquired on a 1.5-T system for patients with multiple sclerosis (MS). METHODS Prospective study that involved twenty-seven consecutive relapsing-remitting MS patients scanned on a 1.5-T MRI scanner. The MRI protocol included 2D transverse conventional spin-echo sequences: proton density-weighted (PD), T2-weighted, T2-FLAIR, and T1-weighted. Synthetic images were generated using 2D transverse QRAPMASTER and SyMRI software with the same voxel size, repetition, echo, and inversion times as the conventional sequences. Four raters performed a crosstab qualitative analysis that involved evaluating global image quality, contrast, flow artefacts, and confidence in lesion assessment introducing the concepts of predominance, agreement, and disagreement. A quantitative analysis was also performed and included evaluating the number of lesions (periventricular, juxtacortical, brainstem, and cerebellum) and the contrast-to-noise ratio between regions (CSF, white matter, grey matter, lesions). RESULTS The global image quality assessment showed predominance for better scores for conventional sequences over synthetic sequences, whereas contrast, confidence in lesion assessment, and flow artefacts showed predominance for agreement between sequences. There was predominance for disagreement between all pairs of raters in most of the evaluated qualitative parameters. Synthetic PD and T2-FLAIR images showed higher contrast-to-noise ratios than the corresponding conventional images for most comparison between regions. There were no significant differences in the number of lesions detected for most of the study regions between conventional and synthetic images. CONCLUSION Synthetic MRI can be potentially used as an alternative to conventional brain MRI sequences in the assessment of MS.
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Zheng Z, Yang J, Zhang D, Ma J, Yin H, Liu Y, Wang Z. The effect of scan parameters on T1, T2 relaxation times measured with multi-dynamic multi-echo sequence: a phantom study. Phys Eng Sci Med 2022; 45:657-664. [PMID: 35553390 PMCID: PMC9239947 DOI: 10.1007/s13246-022-01128-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 04/18/2022] [Indexed: 11/23/2022]
Abstract
Multi-Dynamic Multi-Echo (MDME) Sequence is a new method which can acquire various contrast-weighted images using quantitative relaxometric parameters measured from multicontrast images. The purpose of our study was to investigate the effect of scan parameters of MDME Sequence on measured T1, T2 values of phantoms at 3.0 T MRI scanner. Gray matter, white matter and cerebrospinal fluid simulation phantoms with different relaxation times (named GM, WM, CSF, respectively) were used in our study. All the phantoms were scanned 9 times on different days using MDME sequence with variations of echo train length, matrix, and acceleration factor. The T1, T2 measurements were acquired after each acquisition. The repeatability was characterized as the intragroup coefficient of variation (CV) of measured values over 9 times, and the discrepancies of measurements across different groups were characterized as intergroup CVs. The highest intragroup CVs of T1-GM, T2-GM, T1-WM, T2-WM, T1-CSF, T2-SCF were 1.36%, 1.75%, 0.74%, 1.41%, 1.70%, 7.79%, respectively. The highest intergroup CVs of T1-GM, T2-GM, T1-WM, T2-WM, T1-CSF, T2-SCF were 0.54%, 1.86%, 1.70%, 0.94%, 1.00%, 2.17%, respectively. Quantitative T1, T2 measurements of gray matter, white matter and cerebrospinal fluid simulation phantoms derived from the MDME sequence were not obviously affected by variations of scanning parameters, such as echo train length, matrix, and acceleration factor on 3T scanner.
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Affiliation(s)
- Zuofeng Zheng
- Department of Radiology, Beijing Friendship Hospital, Capital Medical University, Yong An Road 95, Beijing, 100050, China.,Department of Radiology, Beijing ChuiYangLiu Hospital, Beijing, China
| | - Jiafei Yang
- Department of Radiology, Beijing ChuiYangLiu Hospital, Beijing, China
| | - Dongpo Zhang
- Department of Radiology, Beijing ChuiYangLiu Hospital, Beijing, China
| | - Jun Ma
- Department of Radiology, Beijing ChuiYangLiu Hospital, Beijing, China
| | - Hongxia Yin
- Department of Radiology, Beijing Friendship Hospital, Capital Medical University, Yong An Road 95, Beijing, 100050, China
| | - Yawen Liu
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Zhenchang Wang
- Department of Radiology, Beijing Friendship Hospital, Capital Medical University, Yong An Road 95, Beijing, 100050, China.
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Hwang KP, Fujita S. Synthetic MR: Physical principles, clinical implementation, and new developments. Med Phys 2022; 49:4861-4874. [PMID: 35535442 DOI: 10.1002/mp.15686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 04/05/2022] [Accepted: 04/08/2022] [Indexed: 11/07/2022] Open
Abstract
Current clinical MR imaging practices rely on the qualitative assessment of images for diagnosis and treatment planning. While contrast in MR images is dependent on the spin parameters of the imaged tissue, pixel values on MR images are relative and are not scaled to represent any tissue properties. Synthetic MR is a fully featured imaging workflow consisting of efficient multiparameter mapping acquisition, synthetic image generation, and volume quantitation of brain tissues. As the application becomes more widely available on multiple vendors and scanner platforms, it has also gained widespread adoption as clinicians begin to recognize the benefits of rapid quantitation. This review will provide details about the sequence with a focus on the physical principles behind its relaxometry mechanisms. It will present an overview of the products in their current form and some potential issues when implementing it in the clinic. It will conclude by highlighting some recent advances of the technique, including a 3D mapping method and its associated applications. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Ken-Pin Hwang
- Department of Imaging Physics, The University of Texas M.D. Anderson Cancer Center, Houston, TX, 77030
| | - Shohei Fujita
- Department of Radiology, Graduate School of Medicine, The University of Tokyo.,Department of Radiology, Juntendo University, Tokyo, Japan
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Arita Y, Akita H, Fujiwara H, Hashimoto M, Shigeta K, Kwee TC, Yoshida S, Kosaka T, Okuda S, Oya M, Jinzaki M. Synthetic magnetic resonance imaging for primary prostate cancer evaluation: Diagnostic potential of a non-contrast-enhanced bi-parametric approach enhanced with relaxometry measurements. Eur J Radiol Open 2022; 9:100403. [PMID: 35242886 PMCID: PMC8857584 DOI: 10.1016/j.ejro.2022.100403] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/09/2022] [Indexed: 12/28/2022] Open
Abstract
Purpose Bi-parametric magnetic resonance imaging (bpMRI) with diffusion-weighted images has wide utility in diagnosing clinically significant prostate cancer (csPCa). However, bpMRI yields more false-negatives for PI-RADS category 3 lesions than multiparametric (mp)MRI with dynamic-contrast-enhanced (DCE)-MRI. We investigated the utility of synthetic MRI with relaxometry maps for bpMRI-based diagnosis of csPCa. Methods One hundred and five treatment-naïve patients who underwent mpMRI and synthetic MRI before prostate biopsy for suspected PCa between August 2019 and December 2020 were prospectively included. Three experts and three basic prostate radiologists evaluated the diagnostic performance of conventional bpMRI and synthetic bpMRI for csPCa. PI-RADS version 2.1 category 3 lesions were identified by consensus, and relaxometry measurements (T1-value, T2-value, and proton density [PD]) were performed. The diagnostic performance of relaxometry measurements for PI-RADS category 3 lesions in peripheral zone was compared with that of DCE-MRI. Histopathological evaluation results were used as the reference standard. Statistical analysis was performed using the areas under the receiver operating characteristic curve (AUC) and McNemar test. Results In 102 patients without significant MRI artefacts, the diagnostic performance of conventional bpMRI was not significantly different from that of synthetic bpMRI for all readers (p = 0.11–0.79). The AUCs of the combination of T1-value, T2-value, and PD (T1 + T2 + PD) for csPCa in peripheral zone for PI-RADS category 3 lesions were 0.85 for expert and 0.86 for basic radiologists, with no significant difference between T1 + T2 + PD and DCE-MRI for both expert and basic radiologists (p = 0.29–0.45). Conclusion Synthetic MRI with relaxometry maps shows promise for contrast media-free evaluation of csPCa. Diagnostic performances of synthetic bpMRI and conventional bpMRI are comparable for primary PCa Diagnostic performance of synthetic MRI variables are similar to that of DCE-MRI for csPCa in PZ Synthetic bpMRI shows potential as a contrast agent-free method for primary PCa
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Liu Y, Niu H, Ren P, Ren J, Wei X, Liu W, Ding H, Li J, Xia J, Zhang T, Lv H, Yin H, Wang Z. Generation of quantification maps and weighted images from synthetic magnetic resonance imaging using deep learning network. Phys Med Biol 2021; 67. [PMID: 34965516 DOI: 10.1088/1361-6560/ac46dd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 12/29/2021] [Indexed: 11/12/2022]
Abstract
OBJECTIVE The generation of quantification maps and weighted images in synthetic MRI techniques is based on complex fitting equations. This process requires longer image generation times. The objective of this study is to evaluate the feasibility of deep learning method for fast reconstruction of synthetic MRI. APPROACH A total of 44 healthy subjects were recruited and random divided into a training set (30 subjects) and a testing set (14 subjects). A multiple-dynamic, multiple-echo (MDME) sequence was used to acquire synthetic MRI images. Quantification maps (T1, T2, and proton density (PD) maps) and weighted (T1W, T2W, and T2W FLAIR) images were created with MAGiC software and then used as the ground truth images in the deep learning (DL) model. An improved multichannel U-Net structure network was trained to generate quantification maps and weighted images from raw synthetic MRI imaging data (8 module images). Quantitative evaluation was performed on quantification maps. Quantitative evaluation metrics, as well as qualitative evaluation were used in weighted image evaluation. Nonparametric Wilcoxon signed-rank tests were performed in this study. MAIN RESULTS The results of quantitative evaluation show that the error between the generated quantification images and the reference images is small. For weighted images, no significant difference in overall image quality or SNR was identified between DL images and synthetic images. Notably, the DL images achieved improved image contrast with T2W images, and fewer artifacts were present on DL images than synthetic images acquired by T2W FLAIR. SIGNIFICANCE The DL algorithm provides a promising method for image generation in synthetic MRI techniques, in which every step of the calculation can be optimized and faster, thereby simplifying the workflow of synthetic MRI techniques.
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Affiliation(s)
- Yawen Liu
- School of Biological Science and Medical Engineering, Beihang University, Xueyuan Road 100 hectares, Beijing, 100191, CHINA
| | - Haijun Niu
- School of Biological Science and Medical Engineering, Beihang University, Xueyuan Road 100 hectares, Beijing, 100191, CHINA
| | - Pengling Ren
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, 100050, CHINA
| | - Jialiang Ren
- GE Healthcare Beijing, ., Beijing, 100176, CHINA
| | - Xuan Wei
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, Beijing, 100050, CHINA
| | - Wenjuan Liu
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, Beijing, 100050, CHINA
| | - Heyu Ding
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, Beijing, 100050, CHINA
| | - Jing Li
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, Beijing, 100050, CHINA
| | | | - Tingting Zhang
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, Beijing, 100050, CHINA
| | - Han Lv
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, Beijing, 100050, CHINA
| | - Hongxia Yin
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, Beijing, 100050, CHINA
| | - Zhenchang Wang
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Yong'an Road 36, Beijing, Beijing, 100050, CHINA
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Wang Q, Wang G, Sun Q, Sun DH. Application of MAGnetic resonance imaging compilation in acute ischemic stroke. World J Clin Cases 2021; 9:10828-10837. [PMID: 35047594 PMCID: PMC8678888 DOI: 10.12998/wjcc.v9.i35.10828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/31/2021] [Accepted: 10/25/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Synthetic magnetic resonance imaging (MRI) MAGnetic resonance imaging compilation (MAGiC) is a new MRI technology. Conventional T1, T2, T2-fluid-attenuated inversion recovery (FLAIR) contrast images, quantitative images of T1 and T2 mapping, and MAGiC phase sensitive inversion recovery (PSIR) Vessel cerebrovascular images can be obtained simultaneously through post-processing at the same time after completing a scan. In recent years, studies have reported that MAGiC can be applied to patients with acute ischemic stroke. We hypothesized that the synthetic MRI vascular screening scheme can evaluate the degree of cerebral artery stenosis in patients with acute ischemic stroke.
AIM To explore the application value of vascular images obtained by synthetic MRI in diagnosing acute ischemic stroke.
METHODS A total of 64 patients with acute ischemic stroke were selected and examined by MRI in the current retrospective cohort study. The scanning sequences included traditional T1, T2, and T2-FLAIR, three-dimensional time-of-flight magnetic resonance angiography (3D TOF MRA), diffusion-weighted imaging (DWI), and synthetic MRI. Conventional contrast images (T1, T2, and T2-FLAIR) and intracranial vessel images (MAGiC PSIR Vessel] were automatically reconstructed using synthetic MRI raw data. The contrast-to-noise ratio (CNR) values of traditional T1, T2, and T2-FLAIR images and MAGiC reconstructed T1, T2, and T2-FLAIR images in DWI diffusion restriction areas were measured and compared. MAGiC PSIR Vessel and TOF MRA images were used to measure and calculate the stenosis degree of bilateral middle cerebral artery stenosis areas. The consistency of MAGiC PSIR Vessel and TOF MRA in displaying the degree of vascular stenosis with computed tomography angiography (CTA) was compared.
RESULTS Among the 64 patients with acute ischemic stroke, 79 vascular stenosis areas showed that the correlation between MAGiC PSIR Vessel and CTA (r = 0.90, P < 0.01) was higher than that between TOF MRA and CTA (r = 0.84, P < 0.01). With a degree of vascular stenosis > 50% assessed by CTA as a reference, the area under the receiver operating characteristic (ROC) curve of MAGiC PSIR Vessel [area under the curve (AUC) = 0.906, P < 0.01] was higher than that of TOF MRA (AUC = 0.790, P < 0.01). Among the 64 patients with acute ischemic stroke, 39 were scanned for traditional T1, T2, and T2-FLAIR images and MAGiC images simultaneously, and CNR values in DWI diffusion restriction areas were measured, which were: Traditional T2 = 21.2, traditional T1 = -6.7, and traditional T2-FLAIR = 11.9; and MAGiC T2 = 7.1, MAGiC T1 = -3.9, and MAGiC T2-FLAIR = 4.5.
CONCLUSION The synthetic MRI vascular screening scheme for patients with acute ischemic stroke can accurately evaluate the degree of bilateral middle cerebral artery stenosis, which is of great significance to early thrombolytic interventional therapy and improving patients’ quality of life.
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Affiliation(s)
- Qi Wang
- Department of Radiology, The Stroke Hospital of Liaoning Province, Shenyang 110101, Liaoning Province, China
| | - Gang Wang
- Department of Radiology, The Stroke Hospital of Liaoning Province, Shenyang 110101, Liaoning Province, China
| | - Qiang Sun
- Department of Radiology, The Stroke Hospital of Liaoning Province, Shenyang 110101, Liaoning Province, China
| | - Di-He Sun
- Department of Radiology, The Stroke Hospital of Liaoning Province, Shenyang 110101, Liaoning Province, China
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Yang J, Song Y, Huang J, Qu J, Jiao S, Wu P, Chen M. A pilot study of the association between leukoaraiosis and cerebral atherosclerosis using synthetic magnetic resonance imaging. Acta Radiol 2021; 63:1546-1553. [PMID: 34851170 DOI: 10.1177/02841851211044970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Leukoaraiosis is a type of lesion characterized by tissue rarefaction or myelin pallor resulting from axons loss and gliosis. Synthetic magnetic resonance imaging (MRI) could yield quantitative T1, T2, proton density (PD) values of leukoaraiosis in addition to information on the volume of the lesion. PURPOSE To investigate the feasibility of quantifying leukoaraiosis using synthetic MRI and to explore the association between leukoaraiosis and cerebral small vascular diseases and cerebral atherosclerosis. MATERIAL AND METHODS Patients with acute ischemic stroke were enrolled in this study. All participants underwent a conventional T2-weighted image, brain volume, CUBE fluid attenuated inversion recovery, and synthetic MRI acquisition using a 3.0-T MR system. A time-of-flight magnetic resonance angiography was also obtained. We evaluated the T1, T2, PD values and leukoaraiosis volume. RESULTS Analysis of the leukoaraiosis volume ratios demonstrated a positive association with T2 values, a negative association with T1 values, and no association with PD values. Leukoaraiosis volume ratios were independently correlated with age (P < 0.001), lacunes (P = 0.022), and cerebral microbleeds (P = 0.010). A statistical association was found between both age (P < 0.001) and lacunes (P = 0.047) and leukoaraiosis T2 values. CONCLUSION Synthetic MRI may enhance the evaluation of leukoaraiosis, in addition to providing information on its volume. Leukoaraiosis may represent a type of cerebral small vascular disease rather than cerebral atherosclerosis and may share the same pathological mechanism as lacunes and cerebral microbleeds.
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Affiliation(s)
- Jingdong Yang
- Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, PR China
- Department of Ultrasound Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing, PR China
| | - Yan Song
- Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, PR China
| | - Juan Huang
- Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, PR China
| | - Jianxun Qu
- GE Healthcare, MR Research, China, Beijing, PR China
| | - Sheng Jiao
- Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, PR China
| | - Puyeh Wu
- GE Healthcare, MR Research, China, Beijing, PR China
| | - Min Chen
- Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, PR China
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Kimura T, Yamashita K, Fukatsu K. Synthetic MRI with T 2-based Water Suppression to Reduce Hyperintense Artifacts due to CSF-Partial Volume Effects in the Brain. Magn Reson Med Sci 2021; 20:325-337. [PMID: 33071246 PMCID: PMC8922351 DOI: 10.2463/mrms.mp.2020-0044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Purpose: Our purpose was to assess our proposed new synthetic MRI (synMRI) technique, combined with T2-based water suppression (T2wsup), to reduce cerebral spinal fluid (CSF)–partial volume effects (PVEs). These PVEs are problematic in the T2-weighted fluid-attenuation inversion recovery (FLAIR) images obtained by conventional synMRI techniques. Methods: Our T2wsup was achieved by subtracting additionally acquired long TE spin echo (SE) images of water signals dominant from the originally acquired images after T2 decay correction and a masking on the long TE image using the water volume (Vw) map to preserve tissue SNR, followed by quantitative mapping and then calculation of the synthetic images. A simulation study based on a two-compartment model including tissue and water in a voxel and a volunteer MR study were performed to assess our proposed method. Parameters of long TE and a threshold value in the masking were assessed and optimized experimentally. Quantitative parameter maps of standard and with T2wsup were generated, then wsup-synthetic FLAIR and SE images were calculated using those suitable combinations and compared. Results: Our simulation clarified that the CSF–PVE artifacts in the standard synthetic FLAIR increase T2 as the water volume increases in a voxel, and the volunteer MR brain study demonstrated that the hyperintense artifacts on synthetic images were reduced to < 10% of Vw in those with the standard synMRI while keeping the tissue SNR by selecting optimal masking parameters on additional long TE images of TE = 300 ms. In addition, the wsup-synthetic SE provided better gray-white matter contrasts compared with the wsup-synthetic FLAIR while keeping CSF suppression. Conclusion: Our proposed T2wsup-synMRI technique makes it easy to reduce the CSF–PVE artifacts problematic in the synthetic FLAIR images using the current synMRI technique by adding long TE images and simple processing. Although further optimizations in data acquisition and processing techniques are required before actual clinical use, we expect our technique to become clinically useful.
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Affiliation(s)
- Tokunori Kimura
- Department of Radiological Science, Shizuoka College of Medicalcare Science
| | - Kousuke Yamashita
- Department of Radiological Science, Shizuoka College of Medicalcare Science
| | - Kouta Fukatsu
- Department of Radiological Science, Shizuoka College of Medicalcare Science
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Ji S, Jeong J, Oh SH, Nam Y, Choi SH, Shin HG, Shin D, Jung W, Lee J. Quad-Contrast Imaging: Simultaneous Acquisition of Four Contrast-Weighted Images (PD-Weighted, T₂-Weighted, PD-FLAIR and T₂-FLAIR Images) With Synthetic T₁-Weighted Image, T₁- and T₂-Maps. IEEE TRANSACTIONS ON MEDICAL IMAGING 2021; 40:3617-3626. [PMID: 34191724 DOI: 10.1109/tmi.2021.3093617] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Magnetic resonance imaging (MRI) can provide multiple contrast-weighted images using different pulse sequences and protocols. However, a long acquisition time of the images is a major challenge. To address this limitation, a new pulse sequence referred to as quad-contrast imaging is presented. The quad-contrast sequence enables the simultaneous acquisition of four contrast-weighted images (proton density (PD)-weighted, T2-weighted, PD-fluid attenuated inversion recovery (FLAIR), and T2-FLAIR), and the synthesis of T1-weighted images and T1- and T2-maps in a single scan. The scan time is less than 6 min and is further reduced to 2 min 50 s using a deep learning-based parallel imaging reconstruction. The natively acquired quad contrasts demonstrate high quality images, comparable to those from the conventional scans. The deep learning-based reconstruction successfully reconstructed highly accelerated data (acceleration factor 6), reporting smaller normalized root mean squared errors (NRMSEs) and higher structural similarities (SSIMs) than those from conventional generalized autocalibrating partially parallel acquisitions (GRAPPA)-reconstruction (mean NRMSE of 4.36% vs. 10.54% and mean SSIM of 0.990 vs. 0.953). In particular, the FLAIR contrast is natively acquired and does not suffer from lesion-like artifacts at the boundary of tissue and cerebrospinal fluid, differentiating the proposed method from synthetic imaging methods. The quad-contrast imaging method may have the potentials to be used in a clinical routine as a rapid diagnostic tool.
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Parlak S, Coban G, Gumeler E, Karakaya J, Soylemezoglu F, Tezer I, Bilginer B, Saygi S, Oguz KK. Reduced myelin in patients with isolated hippocampal sclerosis as assessed by SyMRI. Neuroradiology 2021; 64:99-107. [PMID: 34611716 PMCID: PMC8492040 DOI: 10.1007/s00234-021-02824-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/25/2021] [Indexed: 02/05/2023]
Abstract
Purpose Synthetic MRI (SyMRI) enables to quantify brain tissue and morphometry. We aimed to investigate the WM and myelin alterations in patients with unilateral hippocampal sclerosis (HS) with SyMRI. Methods Adult patients with isolated unilateral HS and age-matched control subjects (CSs) were included in this study. The SyMRI sequence QRAPMASTER in the coronal plane perpendicular to the hippocampi was obtained from the whole brain. Automatic segmentation of the whole brain was processed by SyMRI Diagnostic software (Version 11.2). Two neuroradiologists also performed quantitative analyses independently from symmetrical 14 ROIs placed in temporal and extratemporal WM, hippocampi, and amygdalae in both hemispheres. Results Sixteen patients (F/M = 6/10, mean age = 32.5 ± 11.3 years; right/left HS: 8/8) and 10 CSs (F/M = 5/5, mean age = 30.7 ± 7 years) were included. Left HS patients had significantly lower myelin and WM volumes than CSs (p < .05). Myelin was reduced significantly in the ipsilateral temporal lobe of patients than CSs, greater in left HS (p < .05). Histopathological examination including luxol fast blue stain also revealed myelin pallor in all of 6 patients who were operated. Ipsilateral temporal pole and sub-insular WM had significantly reduced myelin than the corresponding contralateral regions in patients (p < .05). No significant difference was found in WM values. GM values were significantly lower in hippocampi in patients than CSs (p < .05). Conclusion SyMRI revealed myelin reduction in the ipsilateral temporal lobe and sub-insular WM of patients with HS. Whether this finding correlates with electrophysiological features and SyMRI could serve as lateralization of temporal lobe epilepsy need to be investigated. Supplementary Information The online version contains supplementary material available at 10.1007/s00234-021-02824-6.
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Affiliation(s)
- Safak Parlak
- Department of Radiology, Hacettepe University Faculty of Medicine, Ankara, Turkey.
| | - Gokcen Coban
- Department of Radiology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Ekim Gumeler
- Department of Radiology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Jale Karakaya
- Department of Biostatistics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Figen Soylemezoglu
- Department of Pathology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Irsel Tezer
- Department of Neurology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Burcak Bilginer
- Department of Neurosurgery, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Serap Saygi
- Department of Neurology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Kader K Oguz
- Department of Radiology, Hacettepe University Faculty of Medicine, Ankara, Turkey
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Martin D, Tong E, Kelly B, Yeom K, Yedavalli V. Current Perspectives of Artificial Intelligence in Pediatric Neuroradiology: An Overview. FRONTIERS IN RADIOLOGY 2021; 1:713681. [PMID: 37492174 PMCID: PMC10365125 DOI: 10.3389/fradi.2021.713681] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 07/21/2021] [Indexed: 07/27/2023]
Abstract
Artificial Intelligence, Machine Learning, and myriad related techniques are becoming ever more commonplace throughout industry and society, and radiology is by no means an exception. It is essential for every radiologists of every subspecialty to gain familiarity and confidence with these techniques as they become increasingly incorporated into the routine practice in both academic and private practice settings. In this article, we provide a brief review of several definitions and techniques that are commonly used in AI, and in particular machine vision, and examples of how they are currently being applied to the setting of clinical neuroradiology. We then review the unique challenges that the adoption and application of faces within the subspecialty of pediatric neuroradiology, and how these obstacles may be overcome. We conclude by presenting specific examples of how AI is currently being applied within the field of pediatric neuroradiology and the potential opportunities that are available for future applications.
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Affiliation(s)
- Dann Martin
- Vanderbilt University, Nashville, TN, United States
| | - Elizabeth Tong
- Department of Neuroradiology, Stanford Health Care, Stanford, CA, United States
| | - Brendan Kelly
- Insight Centre for Data Analytics, University College Dublin, Dublin, Ireland
| | - Kristen Yeom
- Department of Neuroradiology, Stanford Health Care, Stanford, CA, United States
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Lavrova E, Lommers E, Woodruff HC, Chatterjee A, Maquet P, Salmon E, Lambin P, Phillips C. Exploratory Radiomic Analysis of Conventional vs. Quantitative Brain MRI: Toward Automatic Diagnosis of Early Multiple Sclerosis. Front Neurosci 2021; 15:679941. [PMID: 34421515 PMCID: PMC8374240 DOI: 10.3389/fnins.2021.679941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/14/2021] [Indexed: 12/23/2022] Open
Abstract
Conventional magnetic resonance imaging (cMRI) is poorly sensitive to pathological changes related to multiple sclerosis (MS) in normal-appearing white matter (NAWM) and gray matter (GM), with the added difficulty of not being very reproducible. Quantitative MRI (qMRI), on the other hand, attempts to represent the physical properties of tissues, making it an ideal candidate for quantitative medical image analysis or radiomics. We therefore hypothesized that qMRI-based radiomic features have added diagnostic value in MS compared to cMRI. This study investigated the ability of cMRI (T1w) and qMRI features extracted from white matter (WM), NAWM, and GM to distinguish between MS patients (MSP) and healthy control subjects (HCS). We developed exploratory radiomic classification models on a dataset comprising 36 MSP and 36 HCS recruited in CHU Liege, Belgium, acquired with cMRI and qMRI. For each image type and region of interest, qMRI radiomic models for MS diagnosis were developed on a training subset and validated on a testing subset. Radiomic models based on cMRI were developed on the entire training dataset and externally validated on open-source datasets with 167 HCS and 10 MSP. Ranked by region of interest, the best diagnostic performance was achieved in the whole WM. Here the model based on magnetization transfer imaging (a type of qMRI) features yielded a median area under the receiver operating characteristic curve (AUC) of 1.00 in the testing sub-cohort. Ranked by image type, the best performance was achieved by the magnetization transfer models, with median AUCs of 0.79 (0.69–0.90, 90% CI) in NAWM and 0.81 (0.71–0.90) in GM. The external validation of the T1w models yielded an AUC of 0.78 (0.47–1.00) in the whole WM, demonstrating a large 95% CI and a low sensitivity of 0.30 (0.10–0.70). This exploratory study indicates that qMRI radiomics could provide efficient diagnostic information using NAWM and GM analysis in MSP. T1w radiomics could be useful for a fast and automated check of conventional MRI for WM abnormalities once acquisition and reconstruction heterogeneities have been overcome. Further prospective validation is needed, involving more data for better interpretation and generalization of the results.
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Affiliation(s)
- Elizaveta Lavrova
- The D-Lab, Department of Precision Medicine, GROW-School for Oncology, Maastricht University, Maastricht, Netherlands.,GIGA Cyclotron Research Centre In Vivo Imaging, University of Liège, Liège, Belgium
| | - Emilie Lommers
- GIGA Cyclotron Research Centre In Vivo Imaging, University of Liège, Liège, Belgium.,Clinical Neuroimmunology Unit, Neurology Department, CHU Liège, Liège, Belgium
| | - Henry C Woodruff
- The D-Lab, Department of Precision Medicine, GROW-School for Oncology, Maastricht University, Maastricht, Netherlands.,Department of Radiology and Nuclear Imaging, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Avishek Chatterjee
- The D-Lab, Department of Precision Medicine, GROW-School for Oncology, Maastricht University, Maastricht, Netherlands
| | - Pierre Maquet
- GIGA Cyclotron Research Centre In Vivo Imaging, University of Liège, Liège, Belgium.,Clinical Neuroimmunology Unit, Neurology Department, CHU Liège, Liège, Belgium
| | - Eric Salmon
- GIGA Cyclotron Research Centre In Vivo Imaging, University of Liège, Liège, Belgium
| | - Philippe Lambin
- The D-Lab, Department of Precision Medicine, GROW-School for Oncology, Maastricht University, Maastricht, Netherlands.,Department of Radiology and Nuclear Imaging, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Christophe Phillips
- GIGA Cyclotron Research Centre In Vivo Imaging, University of Liège, Liège, Belgium.,GIGA In Silico Medicine, University of Liège, Liège, Belgium
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Montejo C, Laredo C, Llull L, Martínez-Heras E, López-Rueda A, Torné R, Garrido C, Bargallo N, Llufriu S, Amaro S. Synthetic MRI in subarachnoid haemorrhage. Clin Radiol 2021; 76:785.e17-785.e23. [PMID: 34193343 DOI: 10.1016/j.crad.2021.05.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 05/26/2021] [Indexed: 11/28/2022]
Abstract
AIM To evaluate the reliability of synthetic magnetic resonance imaging (SyMRI) for detecting complications associated with subarachnoid haemorrhage (SAH), such as ischaemic lesions, hydrocephalus, or bleeding complications. MATERIALS AND METHODS Twenty patients with SAH, who underwent a conventional brain MRI and a SyMRI on a 3 T MRI machine. Comparable conventional and synthetic T2-weighted fluid attenuated inversion recovery (FLAIR) images were acquired. The presence of ischaemic lesions, hydrocephalus, extra-axial blood collections as well as the volumes of grey matter (GMv), white matter (WMv), and cerebrospinal (CSFv) were compared. The acquisition times of both sequences was also analysed. RESULTS The concordance between the two techniques was excellent for the detection of ischaemic lesions and extra-axial collections (kappa = 0.80 and 0.88 respectively) and good for the detection of hydrocephalus (kappa = 0.69). No significant differences were detected in the number of ischaemic lesions (p=0.31) or in the Evans index (p=0.11). The WMv and CSFv measures were also similar (p=0.18 and p=0.94, respectively), as well as the volume of ischaemic lesions (p=0.79). Compared to conventional MRI, the SyMRI acquisition time was shorter regardless of the number of sections (32% and 6% time reduction for 4 or 3 mm section thickness, respectively). CONCLUSIONS SyMRI allows the detection of potential complications of SAH in a similar way to conventional MRI with a shorter acquisition time.
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Affiliation(s)
- C Montejo
- Center for Neuroimmunology and Advanced Imaging in Neuroimmunological Diseases (ImaginEM), Hospital Clinic, University of Barcelona and August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - C Laredo
- Comprehensive Stroke Center, Department of Neurology, Neuroscience Institute, Hospital Clinic, University of Barcelona and August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - L Llull
- Comprehensive Stroke Center, Department of Neurology, Neuroscience Institute, Hospital Clinic, University of Barcelona and August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - E Martínez-Heras
- Center for Neuroimmunology and Advanced Imaging in Neuroimmunological Diseases (ImaginEM), Hospital Clinic, University of Barcelona and August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - A López-Rueda
- Radiology Department, Hospital Clinic, Barcelona, Spain
| | - R Torné
- Neurosurgery Department, Neuroscience Institute, Hospital Clinic, Barcelona, Spain
| | - C Garrido
- Radiology Department, Hospital Clinic, Barcelona, Spain; Magnetic Resonance Core Facility August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - N Bargallo
- Radiology Department, Hospital Clinic, Barcelona, Spain; Magnetic Resonance Core Facility August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - S Llufriu
- Center for Neuroimmunology and Advanced Imaging in Neuroimmunological Diseases (ImaginEM), Hospital Clinic, University of Barcelona and August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain.
| | - S Amaro
- Comprehensive Stroke Center, Department of Neurology, Neuroscience Institute, Hospital Clinic, University of Barcelona and August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain.
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Ryu K, Lee JH, Nam Y, Gho SM, Kim HS, Kim DH. Accelerated multicontrast reconstruction for synthetic MRI using joint parallel imaging and variable splitting networks. Med Phys 2021; 48:2939-2950. [PMID: 33733464 DOI: 10.1002/mp.14848] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 11/10/2022] Open
Abstract
PURPOSE Synthetic magnetic resonance imaging (MRI) requires the acquisition of multicontrast images to estimate quantitative parameter maps, such as T1 , T2 , and proton density (PD). The study aims to develop a multicontrast reconstruction method based on joint parallel imaging (JPI) and joint deep learning (JDL) to enable further acceleration of synthetic MRI. METHODS The JPI and JDL methods are extended and combined to improve reconstruction for better-quality, synthesized images. JPI is performed as a first step to estimate the missing k-space lines, and JDL is then performed to correct and refine the previous estimate with a trained neural network. For the JDL architecture, the original variable splitting network (VS-Net) is modified and extended to form a joint variable splitting network (JVS-Net) to apply to multicontrast reconstructions. The proposed method is designed and tested for multidynamic multiecho (MDME) images with Cartesian uniform under-sampling using acceleration factors between 4 and 8. RESULTS It is demonstrated that the normalized root-mean-square error (nRMSE) is lower and the structural similarity index measure (SSIM) values are higher with the proposed method compared to both the JPI and JDL methods individually. The method also demonstrates the potential to produce a set of synthesized contrast-weighted images that closely resemble those from the fully sampled acquisition without erroneous artifacts. CONCLUSION Combining JPI and JDL enables the reconstruction of highly accelerated synthetic MRIs.
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Affiliation(s)
- Kanghyun Ryu
- Department of Radiology, Stanford University, Stanford, CA, USA.,Department of Electrical and Electronic Engineering, Yonsei University, Seoul, Republic of Korea
| | - Jae-Hun Lee
- Department of Electrical and Electronic Engineering, Yonsei University, Seoul, Republic of Korea
| | - Yoonho Nam
- Department of Biomedical Engineering, Hankuk University of Foreign Studies, Yongin, Republic of Korea
| | - Sung-Min Gho
- MR Collaboration and Development, GE Healthcare, Seoul, Republic of Korea
| | - Ho-Sung Kim
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Dong-Hyun Kim
- Department of Electrical and Electronic Engineering, Yonsei University, Seoul, Republic of Korea
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Lou B, Jiang Y, Li C, Wu PY, Li S, Qin B, Chen H, Wang R, Wu B, Chen M. Quantitative Analysis of Synthetic Magnetic Resonance Imaging in Alzheimer's Disease. Front Aging Neurosci 2021; 13:638731. [PMID: 33912023 PMCID: PMC8072384 DOI: 10.3389/fnagi.2021.638731] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/18/2021] [Indexed: 12/15/2022] Open
Abstract
Objectives: The purpose of this study was to evaluate the feasibility and whether synthetic MRI can benefit diagnosis of Alzheimer’s disease (AD). Materials and Methods: Eighteen patients and eighteen age-matched normal controls (NCs) underwent MR examination. The mini-mental state examination (MMSE) scores were obtained from all patients. The whole brain volumetric characteristics, T1, T2, and proton density (PD) values of different cortical and subcortical regions were obtained. The volumetric characteristics and brain regional relaxation values between AD patients and NCs were compared using independent-samples t-test. The correlations between these quantitative parameters and MMSE score were assessed by the Pearson correlation in AD patients. Results: Although the larger volume of cerebrospinal fluid (CSF), lower brain parenchymal volume (BPV), and the ratio of brain parenchymal volume to intracranial volume (BPV/ICV) were found in AD patients compared with NCs, there were no significant differences (p > 0.05). T1 values of right insula cortex and T2 values of left hippocampus and right insula cortex were significantly higher in AD patients than in NCs, but T1 values of left caudate showed a reverse trend (p < 0.05). As the MMSE score decreased in AD patients, the BPV and BPV/ICV decreased, while the volume of CSF and T1 values of bilateral insula cortex and bilateral hippocampus as well as T2 values of bilateral hippocampus increased (p < 0.05). Conclusion: Synthetic MRI not only provides more information to differentiate AD patients from normal controls, but also reflects the disease severity of AD.
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Affiliation(s)
- Baohui Lou
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Yuwei Jiang
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Chunmei Li
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | | | - Shuhua Li
- Department of Neurology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Bin Qin
- Department of Neurology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Haibo Chen
- Department of Neurology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Rui Wang
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
| | - Bing Wu
- GE Healthcare, Beijing, China
| | - Min Chen
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China
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Li Q, Xiao Q, Yang M, Chai Q, Huang Y, Wu PY, Niu Q, Gu Y. Histogram analysis of quantitative parameters from synthetic MRI: Correlations with prognostic factors and molecular subtypes in invasive ductal breast cancer. Eur J Radiol 2021; 139:109697. [PMID: 33857828 DOI: 10.1016/j.ejrad.2021.109697] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 03/31/2021] [Accepted: 04/04/2021] [Indexed: 12/12/2022]
Abstract
PURPOSE To evaluate intra-tumoral heterogeneity through a histogram analysis of quantitative parameters obtained from synthetic MRI (magnetic resonance imaging), and determine correlations of these histogram characteristics with prognostic factors and molecular subtypes of invasive ductal carcinoma (IDC). METHODS A total of 122 IDC from 122 women who underwent preoperative synthetic MRI and DCE (dynamic contrast enhancement)-MRI were investigated. The synthetic MRI parameters (T1, T2, and PD (proton density)) were obtained. For each parameter, the minimum, 10th percentile, mean, median, 90th percentile, maximum, skewness, and kurtosis values of tumor were calculated, and correlations with prognostic factors and subtypes were assessed. The Mann-Whitney U test or the Student's t test were utilized to analyze the association between the histogram features of synthetic MRI parameters and prognostic factors. The Kruskal-Wallis test followed by the post-hoc test was used to analyze differences of synthetic MRI parameters among molecular subtypes. RESULTS IDC with high histopathologic grade showed statistically higher PDmaxium, T1mean and T1median values than those with low grade (p = 0.003, p = 0.007, p = 0.003). The T110th were significantly higher in cancers with PR (progesterone receptor) negativity than those with PR positivity (p = 0.005). ER-negative cancers had significant higher values of T210th, T2mean, and T2median than ER-positive cancers (p = 0.006, 0.002, and 0.006, respectively). The values of PDmedian were significantly higher in IDC with HER2 (human epidermal growth factor receptor 2) positivity than those with HER2 negativity (p = 0.001). When discriminating molecular subtypes of IDC, the T2mean achieved the highest performance. The T2mean values of TN (triple-negative), luminal B and luminal A types are arranged in descending order (p < 0.0001). CONCLUSIONS Histogram features derived from synthetic MRI quantifies the distributions of tissue relaxation time and proton density, and may serve as a potential biomarker for discriminating histopathological grade, hormone receptor status, HER2 expression status and breast cancer subtypes.
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Affiliation(s)
- Qin Li
- Department of Radiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Qin Xiao
- Department of Radiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Meng Yang
- Department of Radiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Qinghuan Chai
- Department of Radiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yan Huang
- Department of Radiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | | | - Qingliang Niu
- Department of Radiology, WeiFang Traditional Chinese Hospital, Weizhou Road No. 1055, Weifang, Shandong, China.
| | - Yajia Gu
- Department of Radiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
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Fujioka T, Mori M, Oyama J, Kubota K, Yamaga E, Yashima Y, Katsuta L, Nomura K, Nara M, Oda G, Nakagawa T, Tateishi U. Investigating the Image Quality and Utility of Synthetic MRI in the Breast. Magn Reson Med Sci 2021; 20:431-438. [PMID: 33536401 PMCID: PMC8922358 DOI: 10.2463/mrms.mp.2020-0132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Purpose Synthetic MRI reconstructs multiple sequences in a single acquisition. In the
present study, we aimed to compare the image quality and utility of
synthetic MRI with that of conventional MRI in the breast. Methods We retrospectively collected the imaging data of 37 women (mean age: 55.1
years; range: 20–78 years) who had undergone both synthetic and
conventional MRI of T2-weighted, T1-weighted, and fat-suppressed
(FS)-T2-weighted images. Two independent breast radiologists evaluated the
overall image quality, anatomical sharpness, contrast between tissues, image
homogeneity, and presence of artifacts of synthetic and conventional MRI on
a 5-point scale (5 = very good to 1 =
very poor). The interobserver agreement between the
radiologists was evaluated using weighted kappa. Results For synthetic MRI, the acquisition time was 3 min 28 s. On the 5-point scale
evaluation of overall image quality, although the scores of synthetic
FS-T2-weighted images (4.01 ± 0.56) were lower than that of
conventional images (4.95 ± 0.23; P < 0.001),
the scores of synthetic T1- and T2-weighted images (4.95 ± 0.23 and
4.97 ± 0.16) were comparable with those of conventional images (4.92
± 0.27 and 4.97 ± 0.16; P = 0.484 and
1.000, respectively). The kappa coefficient of conventional MRI was fair
(0.53; P < 0.001), and that of conventional MRI was
fair (0.46; P < 0.001). Conclusion The image quality of synthetic T1- and T2-weighted images was similar to that
of conventional images and diagnostically acceptable, whereas the quality of
synthetic T2-weighted FS images was inferior to conventional images.
Although synthetic MRI images of the breast have the potential to provide
efficient image diagnosis, further validation and improvement are required
for clinical application.
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Affiliation(s)
- Tomoyuki Fujioka
- Department of Diagnostic Radiology, Tokyo Medical and Dental University
| | - Mio Mori
- Department of Diagnostic Radiology, Tokyo Medical and Dental University
| | - Jun Oyama
- Department of Diagnostic Radiology, Tokyo Medical and Dental University
| | - Kazunori Kubota
- Department of Diagnostic Radiology, Tokyo Medical and Dental University.,Department of Radiology, Dokkyo Medical University
| | - Emi Yamaga
- Department of Diagnostic Radiology, Tokyo Medical and Dental University
| | - Yuka Yashima
- Department of Diagnostic Radiology, Tokyo Medical and Dental University
| | - Leona Katsuta
- Department of Diagnostic Radiology, Tokyo Medical and Dental University
| | - Kyoko Nomura
- Department of Diagnostic Radiology, Tokyo Medical and Dental University
| | - Miyako Nara
- Department of Diagnostic Radiology, Tokyo Medical and Dental University.,Department of Breast Surgery, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital
| | - Goshi Oda
- Department of Surgery, Breast Surgery, Tokyo Medical and Dental University
| | - Tsuyoshi Nakagawa
- Department of Surgery, Breast Surgery, Tokyo Medical and Dental University
| | - Ukihide Tateishi
- Department of Diagnostic Radiology, Tokyo Medical and Dental University
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Fujita S, Yokoyama K, Hagiwara A, Kato S, Andica C, Kamagata K, Hattori N, Abe O, Aoki S. 3D Quantitative Synthetic MRI in the Evaluation of Multiple Sclerosis Lesions. AJNR Am J Neuroradiol 2021; 42:471-478. [PMID: 33414234 DOI: 10.3174/ajnr.a6930] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 09/30/2020] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND PURPOSE Synthetic MR imaging creates multiple contrast-weighted images based on a single time-efficient quantitative scan, which has been mostly performed for 2D acquisition. We assessed the utility of 3D synthetic MR imaging in patients with MS by comparing its diagnostic image quality and lesion volumetry with conventional MR imaging. MATERIALS AND METHODS Twenty-four patients with MS prospectively underwent 3D quantitative synthetic MR imaging and conventional T1-weighted, T2-weighted, FLAIR, and double inversion recovery imaging, with acquisition times of 9 minutes 3 seconds and 18 minutes 27 seconds for the synthetic MR imaging and conventional MR imaging sequences, respectively. Synthetic phase-sensitive inversion recovery images and those corresponding to conventional MR imaging contrasts were created for synthetic MR imaging. Two neuroradiologists independently assessed the image quality on a 5-point Likert scale. The numbers of cortical lesions and lesion volumes were quantified using both synthetic and conventional image sets. RESULTS The overall diagnostic image quality of synthetic T1WI and double inversion recovery images was noninferior to that of conventional images (P = .23 and .20, respectively), whereas that of synthetic T2WI and FLAIR was inferior to that of conventional images (both Ps < .001). There were no significant differences in the number of cortical lesions (P = .17 and .53 for each rater) or segmented lesion volumes (P = .61) between the synthetic and conventional image sets. CONCLUSIONS Three-dimensional synthetic MR imaging could serve as an alternative to conventional MR imaging in evaluating MS with a reduced scan time.
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Affiliation(s)
- S Fujita
- From the Departments of Radiology (S.F., A.H., S.K., C.A., K.K., S.A.).,Department of Radiology (S.F., S.K., O.A.), The University of Tokyo, Tokyo, Japan
| | - K Yokoyama
- Neurology (K.Y., N.H.), Juntendo University, Tokyo, Japan
| | - A Hagiwara
- From the Departments of Radiology (S.F., A.H., S.K., C.A., K.K., S.A.)
| | - S Kato
- From the Departments of Radiology (S.F., A.H., S.K., C.A., K.K., S.A.).,Department of Radiology (S.F., S.K., O.A.), The University of Tokyo, Tokyo, Japan
| | - C Andica
- From the Departments of Radiology (S.F., A.H., S.K., C.A., K.K., S.A.)
| | - K Kamagata
- From the Departments of Radiology (S.F., A.H., S.K., C.A., K.K., S.A.)
| | - N Hattori
- Neurology (K.Y., N.H.), Juntendo University, Tokyo, Japan
| | - O Abe
- Department of Radiology (S.F., S.K., O.A.), The University of Tokyo, Tokyo, Japan
| | - S Aoki
- From the Departments of Radiology (S.F., A.H., S.K., C.A., K.K., S.A.)
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40
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Deep Learning Approach for Generating MRA Images From 3D Quantitative Synthetic MRI Without Additional Scans. Invest Radiol 2020; 55:249-256. [PMID: 31977603 DOI: 10.1097/rli.0000000000000628] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES Quantitative synthetic magnetic resonance imaging (MRI) enables synthesis of various contrast-weighted images as well as simultaneous quantification of T1 and T2 relaxation times and proton density. However, to date, it has been challenging to generate magnetic resonance angiography (MRA) images with synthetic MRI. The purpose of this study was to develop a deep learning algorithm to generate MRA images based on 3D synthetic MRI raw data. MATERIALS AND METHODS Eleven healthy volunteers and 4 patients with intracranial aneurysms were included in this study. All participants underwent a time-of-flight (TOF) MRA sequence and a 3D-QALAS synthetic MRI sequence. The 3D-QALAS sequence acquires 5 raw images, which were used as the input for a deep learning network. The input was converted to its corresponding MRA images by a combination of a single-convolution and a U-net model with a 5-fold cross-validation, which were then compared with a simple linear combination model. Image quality was evaluated by calculating the peak signal-to-noise ratio (PSNR), structural similarity index measurements (SSIMs), and high frequency error norm (HFEN). These calculations were performed for deep learning MRA (DL-MRA) and linear combination MRA (linear-MR), relative to TOF-MRA, and compared with each other using a nonparametric Wilcoxon signed-rank test. Overall image quality and branch visualization, each scored on a 5-point Likert scale, were blindly and independently rated by 2 board-certified radiologists. RESULTS Deep learning MRA was successfully obtained in all subjects. The mean PSNR, SSIM, and HFEN of the DL-MRA were significantly higher, higher, and lower, respectively, than those of the linear-MRA (PSNR, 35.3 ± 0.5 vs 34.0 ± 0.5, P < 0.001; SSIM, 0.93 ± 0.02 vs 0.82 ± 0.02, P < 0.001; HFEN, 0.61 ± 0.08 vs 0.86 ± 0.05, P < 0.001). The overall image quality of the DL-MRA was comparable to that of TOF-MRA (4.2 ± 0.7 vs 4.4 ± 0.7, P = 0.99), and both types of images were superior to that of linear-MRA (1.5 ± 0.6, for both P < 0.001). No significant differences were identified between DL-MRA and TOF-MRA in the branch visibility of intracranial arteries, except for ophthalmic artery (1.2 ± 0.5 vs 2.3 ± 1.2, P < 0.001). CONCLUSIONS Magnetic resonance angiography generated by deep learning from 3D synthetic MRI data visualized major intracranial arteries as effectively as TOF-MRA, with inherently aligned quantitative maps and multiple contrast-weighted images. Our proposed algorithm may be useful as a screening tool for intracranial aneurysms without requiring additional scanning time.
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Tachibana Y, Hagiwara A, Hori M, Kershaw J, Nakazawa M, Omatsu T, Kishimoto R, Yokoyama K, Hattori N, Aoki S, Higashi T, Obata T. The Utility of a Convolutional Neural Network for Generating a Myelin Volume Index Map from Rapid Simultaneous Relaxometry Imaging. Magn Reson Med Sci 2020; 19:324-332. [PMID: 31902906 PMCID: PMC7809139 DOI: 10.2463/mrms.mp.2019-0075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Purpose: A current algorithm to obtain a synthetic myelin volume fraction map (SyMVF) from rapid simultaneous relaxometry imaging (RSRI) has a potential problem, that it does not incorporate information from surrounding pixels. The purpose of this study was to develop a method that utilizes a convolutional neural network (CNN) to overcome this problem. Methods: RSRI and magnetization transfer images from 20 healthy volunteers were included. A CNN was trained to reconstruct RSRI-related metric maps into a myelin volume-related index (generated myelin volume index: GenMVI) map using the MVI map calculated from magnetization transfer images (MTMVI) as reference. The SyMVF and GenMVI maps were statistically compared by testing how well they correlated with the MTMVI map. The correlations were evaluated based on: (i) averaged values obtained from 164 atlas-based ROIs, and (ii) pixel-based comparison for ROIs defined in four different tissue types (cortical and subcortical gray matter, white matter, and whole brain). Results: For atlas-based ROIs, the overall correlation with the MTMVI map was higher for the GenMVI map than for the SyMVF map. In the pixel-based comparison, correlation with the MTMVI map was stronger for the GenMVI map than for the SyMVF map, and the difference in the distribution for the volunteers was significant (Wilcoxon sign-rank test, P < 0.001) in all tissue types. Conclusion: The proposed method is useful, as it can incorporate more specific information about local tissue properties than the existing method. However, clinical validation is necessary.
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Affiliation(s)
- Yasuhiko Tachibana
- Applied MRI Research, Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences.,Department of Radiology, Juntendo University School of Medicine
| | - Akifumi Hagiwara
- Department of Radiology, Juntendo University School of Medicine.,Department of Radiology, Graduate School of Medicine, The University of Tokyo
| | - Masaaki Hori
- Department of Radiology, Juntendo University School of Medicine
| | - Jeff Kershaw
- Applied MRI Research, Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences
| | - Misaki Nakazawa
- Department of Radiology, Juntendo University School of Medicine
| | - Tokuhiko Omatsu
- Applied MRI Research, Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences
| | - Riwa Kishimoto
- Applied MRI Research, Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences
| | | | | | - Shigeki Aoki
- Department of Radiology, Juntendo University School of Medicine
| | - Tatsuya Higashi
- Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences
| | - Takayuki Obata
- Applied MRI Research, Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences.,Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences
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Investigation of the feasibility of synthetic MRI in the differential diagnosis of non-keratinising nasopharyngeal carcinoma and benign hyperplasia using different contoured methods for delineation of the region of interest. Clin Radiol 2020; 76:238.e9-238.e15. [PMID: 33213835 DOI: 10.1016/j.crad.2020.10.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 10/21/2020] [Indexed: 12/16/2022]
Abstract
AIM To assess the feasibility and preliminary diagnostic performances of relaxation times derived from synthetic magnetic resonance imaging (syMRI) for differentiating nasopharyngeal carcinoma from nasopharyngeal benign lymphoid hyperplasia, and to assess the influence of tissue segmentation method on relaxation estimates. MATERIALS AND METHODS Fifty participants with nasopharyngeal carcinoma (NPC) and 40 participants with benign hyperplasia (NPH) who underwent syMRI examination were enrolled prospectively. T1, T2, and proton density (PD) values were obtained from four different regions of interest (ROIs), namely, partial-section, single-section, three-sections, and whole-lesion. The metrics between NPC and NPH or among different ROIs were compared using Student's t-test or one-way ANOVA. The area under curve (AUC) was calculated to assess the performance of metrics obtained from different ROIs to differentiate NPC and NPH. RESULTS The T1, T2, and PD values for NPH were significantly higher than those for NPC, regardless of the type of ROI used, except for the PD value obtained from the whole-lesion ROI. The T2 values obtained from the single-section ROI showed the highest diagnostic accuracy in distinguishing NPC from NPH, with an AUC of 0.894, sensitivity of 0.900, and specificity of 0.800. Additionally, the T1, T2, and PD values for nasopharyngeal lesions showed no statistical difference among different kinds of ROI, except for the difference in T1 value between partial-section and other methods. CONCLUSION Quantitative analysis of syMRI has the potential to distinguish NPC from NPH. Moreover, different types of ROI showed limited influence on the relaxation time estimation for nasopharyngeal lesions.
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43
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Ji S, Yang D, Lee J, Choi SH, Kim H, Kang KM. Synthetic MRI: Technologies and Applications in Neuroradiology. J Magn Reson Imaging 2020; 55:1013-1025. [PMID: 33188560 DOI: 10.1002/jmri.27440] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 10/29/2020] [Accepted: 10/29/2020] [Indexed: 12/14/2022] Open
Abstract
Synthetic MRI is a technique that synthesizes contrast-weighted images from multicontrast MRI data. There have been advances in synthetic MRI since the technique was introduced. Although a number of synthetic MRI methods have been developed for quantifying one or more relaxometric parameters and for generating multiple contrast-weighted images, this review focuses on several methods that quantify all three relaxometric parameters (T1 , T2 , and proton density) and produce multiple contrast-weighted images. Acquisition, quantification, and image synthesis techniques are discussed for each method. We discuss the image quality and diagnostic accuracy of synthetic MRI methods and their clinical applications in neuroradiology. Based on this analysis, we highlight areas that need to be addressed for synthetic MRI to be widely implemented in the clinic. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY STAGE: 1.
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Affiliation(s)
- Sooyeon Ji
- Electrical and Computer Engineering, Institute of Engineering Research, Seoul National University, Seoul, Republic of Korea
| | - Dongjin Yang
- Department of Radiology, Daegu Fatima Hospital, Daegu, Republic of Korea
| | - Jongho Lee
- Electrical and Computer Engineering, Institute of Engineering Research, Seoul National University, Seoul, Republic of Korea
| | - Seung Hong Choi
- Electrical and Computer Engineering, Institute of Engineering Research, Seoul National University, Seoul, Republic of Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea
| | - Hyeonjin Kim
- Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea
| | - Koung Mi Kang
- Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea
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44
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Zhang W, Zhu J, Xu X, Fan G. Synthetic MRI of the lumbar spine at 3.0 T: feasibility and image quality comparison with conventional MRI. Acta Radiol 2020; 61:461-470. [PMID: 31522520 DOI: 10.1177/0284185119871670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Background Synthetic magnetic resonance imaging (MRI), which can generate multiple morphologic MR images as well as quantitative maps from a single sequence, is not widely used in the spine at 3.0 T. Purpose To investigate the feasibility of synthetic MRI of the lumbar spine in clinical practice at 3.0 T. Material and Methods Eighty-four patients with lumbar diseases underwent conventional T1-weighted images, T2-weighted images, short-tau inversion recovery (STIR) images, and synthetic MRI of the lumbar spine at 3.0 T. The quantitative and qualitative image quality and agreement for detection of spinal lesions between conventional and synthetic MRI were compared by two radiologists. Results The signal-to-noise ratios of synthetic MRI showed an inferior image quality in the vertebrae and disc, whereas were higher for spinal canal and fat on the synthetic T1-weighted, T2-weighted, and STIR images. The contrast-to-noise ratios of the synthetic MRI was superior to conventional sequences, except for the vertebrae–disc contrast-to-noise ratio on T1-weighted imaging ( P = 0.005). Image quality assessments showed that synthetic MRI had greater STIR fat suppression ( P < 0.001) and fluid brightness ( P = 0.014), as well as higher degree of artifacts ( P < 0.001) and worse spatial resolution ( P = 0.002). The inter-method agreements for detection of spinal lesions were substantial to perfect (kappa, 0.614–0.925). Conclusion Synthetic MRI is a feasible method for lumbar spine imaging in a clinical setting at 3.0-T MR. It provides morphologic sequences with acceptable image quality, good agreement with conventional MRI for detection of spinal lesions and quantitative image maps with a slightly shorter acquisition time compared with conventional MRI.
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Affiliation(s)
- Weilan Zhang
- Department of Radiology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, PR China
| | - Jingyi Zhu
- Department of Radiology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, PR China
| | - Xiaohan Xu
- Department of Radiology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, PR China
| | - Guoguang Fan
- Department of Radiology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province, PR China
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45
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Chougar L, Hagiwara A, Takano N, Andica C, Cohen-Adad J, Warntjes M, Maekawa T, Hori M, Koshino S, Nakazawa M, Abe O, Aoki S. Signal Intensity within Cerebral Venous Sinuses on Synthetic MRI. Magn Reson Med Sci 2020; 19:56-63. [PMID: 30956274 PMCID: PMC7067908 DOI: 10.2463/mrms.mp.2018-0144] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Purpose: Flowing blood sometimes appears bright on synthetic T1-weighted images, which could be misdiagnosed as a thrombus. This study aimed to investigate the frequency of hyperintensity within cerebral venous sinuses on synthetic MR images and to evaluate the influence of increasing flow rates on signal intensity using a flow phantom. Materials and Methods: Imaging data, including synthetic and conventional MRI scans, from 22 patients were retrospectively analyzed. Signal intensities at eight locations of cerebral venous sinuses on synthetic images were graded using the following three-point scale: 0, “dark vessel”; 1, “hyperintensity within the walls”; and 2, “hyperintensity within the lumen.” A phantom with gadolinium solution inside a U-shaped tube was acquired without flow and then with increasing flow rates (60, 100, 200, 300, 400 ml/min). Results: Considering all sinus locations, the venous signal intensity on synthetic T1-weighted images was graded as 2 in 79.8% of the patients. On synthetic T2-weighted images, all sinuses were graded as 0. On fluid-attenuated inversion recovery (FLAIR) images, sinuses were almost always graded as 0 (99.4%). In the phantom study, the signal initially became brighter on synthetic T1-weighted images as the flow rate increased. Above a certain flow rate, the signal started to decrease. Conclusion: High signal intensity within the cerebral venous sinuses is a frequent finding on synthetic T1-weighted images. This corresponds to the hyperintensity noted at certain flow rates in the phantom experiment.
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Affiliation(s)
- Lydia Chougar
- Department of Radiology, Juntendo University School of Medicine.,Department of Radiology, Hôpital Cochin
| | - Akifumi Hagiwara
- Department of Radiology, Juntendo University School of Medicine.,Department of Radiology, Graduate School of Medicine, The University of Tokyo
| | - Nao Takano
- Department of Radiology, Juntendo University School of Medicine
| | | | - Julien Cohen-Adad
- Department of Radiology, Juntendo University School of Medicine.,NeuroPoly Lab, Polytechnique Montreal.,Functional Neuroimaging Unit, CRIUGM, Université de Montréal
| | - Marcel Warntjes
- Center for Medical Imaging Science and Visualization (CMIV), Linköping University.,SyntheticMR AB
| | - Tomoko Maekawa
- Department of Radiology, Juntendo University School of Medicine.,Department of Radiology, Graduate School of Medicine, The University of Tokyo
| | - Masaaki Hori
- Department of Radiology, Juntendo University School of Medicine
| | - Saori Koshino
- Department of Radiology, Juntendo University School of Medicine.,Department of Radiology, Graduate School of Medicine, The University of Tokyo
| | - Misaki Nakazawa
- Department of Radiology, Juntendo University School of Medicine
| | - Osamu Abe
- Department of Radiology, Graduate School of Medicine, The University of Tokyo
| | - Shigeki Aoki
- Department of Radiology, Juntendo University School of Medicine
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46
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Myelin Measurement Using Quantitative Magnetic Resonance Imaging: A Correlation Study Comparing Various Imaging Techniques in Patients with Multiple Sclerosis. Cells 2020; 9:cells9020393. [PMID: 32046340 PMCID: PMC7072333 DOI: 10.3390/cells9020393] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 01/28/2020] [Accepted: 02/06/2020] [Indexed: 12/13/2022] Open
Abstract
Evaluation of myelin by magnetic resonance imaging (MRI) is a difficult challenge, but holds promise in demyelinating diseases, such as multiple sclerosis (MS). Although multiple techniques have been developed, no gold standard has been established. This study aims to evaluate the correlation between synthetic MRI myelin volume fraction (SyMRIMVF) and myelin fraction estimated by other techniques, i.e., magnetization transfer saturation (MTsat), T1-weighted images divided by T2-weighted images (T1w/T2w), and radial diffusivity (RD) in patients with MS. We also compared the sensitivities of these techniques for detecting MS-related myelin damage. SyMRIMVF, MTsat, T1w/T2w, and RD were averaged on plaque, periplaque white matter, and normal-appearing white matter (NAWM). Pairwise correlation was calculated using Spearman’s correlation analysis. For all segmented regions, strong correlations were found between SyMRIMVF and T1w/T2w (Rho = 0.89), MTsat (Rho = 0.82), or RD (Rho = −0.75). For each technique, the average estimated myelin differed significantly among regions, but the percentage change of NAWM from both periplaque white matter and plaque were highest in SyMRIMVF. SyMRIMVF might be suitable for myelin evaluation in MS patients, with relevant results as compared to other well-studied techniques. Moreover, it presented better sensitivity for the detection of the difference between plaque or periplaque white matter and NAWM.
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47
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Cui Y, Han S, Liu M, Wu PY, Zhang W, Zhang J, Li C, Chen M. Diagnosis and Grading of Prostate Cancer by Relaxation Maps From Synthetic MRI. J Magn Reson Imaging 2020; 52:552-564. [PMID: 32027071 DOI: 10.1002/jmri.27075] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/12/2020] [Accepted: 01/13/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The interpretation system for prostate MRI is largely based on qualitative image contrast of different tissue types. Therefore, a fast, standardized, and robust quantitative technique is necessary. Synthetic MRI is capable of quantifying multiple relaxation parameters, which might have potential applications in prostate cancer (PCa). PURPOSE To investigate the use of quantitative relaxation maps derived from synthetic MRI for the diagnosis and grading of PCa. STUDY TYPE Prospective. SUBJECTS In all, 94 men with pathologically confirmed PCa or benign pathological changes. FIELD STRENGTH/SEQUENCE T1 -weighted imaging, T2 -weighted imaging, diffusion-weighted imaging, and synthetic MRI at 3.0T. ASSESSMENT Four kinds of tissue types were identified on pathology, including PCa, stromal hyperplasia (SH), glandular hyperplasia (GH), and noncancerous peripheral zone (PZ). PCa foci were grouped as low-grade (LG, Gleason score ≤6) and intermediate/high-grade (HG, Gleason score ≥7). Regions of interest were manually drawn by two radiologists in consensus on parametric maps according to the pathological results. STATISTICAL TESTS Independent sample t-test, Mann-Whitney U-test, and receiver operating characteristic curve analysis. RESULTS T1 and T2 values of PCa were significantly lower than SH (P = 0.015 and 0.002). The differences of T1 and T2 values between PCa and noncancerous PZ were also significant (P ≤ 0.006). The area under the curve (AUC) of the apparent diffusion coefficient (ADC) value was significantly higher than T1 , T2 , and proton density (PD) values in discriminating PCa from SH and noncancerous PZ (P ≤ 0.025). T2 , PD, and ADC values demonstrated similar diagnostic performance in discriminating LG from HG PCa (AUC = 0.806 [0.640-0.918], 0.717 [0.542-0.854], and 0.817 [0.652-0.925], respectively; P ≥ 0.535). DATA CONCLUSION Relaxation maps derived from synthetic MRI were helpful for discriminating PCa from other benign pathologies. But the overall diagnostic performance was inferior to the ADC values. T2 , PD, and ADC values performed similarly in discriminating LG from HG PCa lesions. LEVEL OF EVIDENCE 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;52:552-564.
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Affiliation(s)
- Yadong Cui
- Department of Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing P. R., China.,Graduate School of Peking Union Medical College, Beijing P. R., China
| | - Siyuan Han
- Department of Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing P. R., China.,Graduate School of Peking Union Medical College, Beijing P. R., China
| | - Ming Liu
- Department of Urology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing P. R., China
| | - Pu-Yeh Wu
- GE Healthcare, MR Research, Beijing P. R., China
| | - Wei Zhang
- Department of Pathology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing P. R., China
| | - Jintao Zhang
- Department of Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing P. R., China
| | - Chunmei Li
- Department of Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing P. R., China
| | - Min Chen
- Department of Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing P. R., China.,Graduate School of Peking Union Medical College, Beijing P. R., China
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48
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Validation of Deep Learning-Based Artifact Correction on Synthetic FLAIR Images in a Different Scanning Environment. J Clin Med 2020; 9:jcm9020364. [PMID: 32013069 PMCID: PMC7074150 DOI: 10.3390/jcm9020364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/26/2020] [Accepted: 01/27/2020] [Indexed: 12/26/2022] Open
Abstract
We investigated the capability of a trained deep learning (DL) model with a convolutional neural network (CNN) in a different scanning environment in terms of ameliorating the quality of synthetic fluid-attenuated inversion recovery (FLAIR) images. The acquired data of 319 patients obtained from the retrospective review were used as test sets for the already trained DL model to correct the synthetic FLAIR images. Quantitative analyses were performed for native synthetic FLAIR and DL-FLAIR images against conventional FLAIR images. Two neuroradiologists assessed the quality and artifact degree of the native synthetic FLAIR and DL-FLAIR images. The quantitative parameters showed significant improvement on DL-FLAIR in all individual tissue segments and total intracranial tissues than on the native synthetic FLAIR (p < 0.0001). DL-FLAIR images showed improved image quality with fewer artifacts than the native synthetic FLAIR images (p < 0.0001). There was no significant difference in the preservation of the periventricular white matter hyperintensities and lesion conspicuity between the two FLAIR image sets (p = 0.217). The quality of synthetic FLAIR images was improved through artifact correction using the trained DL model on a different scan environment. DL-based correction can be a promising solution for ameliorating the quality of synthetic FLAIR images to broaden the clinical use of synthetic magnetic resonance imaging (MRI).
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49
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Assessing the importance of magnetic resonance contrasts using collaborative generative adversarial networks. NAT MACH INTELL 2020. [DOI: 10.1038/s42256-019-0137-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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50
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Di Giuliano F, Minosse S, Picchi E, Marfia GA, Da Ros V, Muto M, Muto M, Pistolese CA, Laghi A, Garaci F, Floris R. Comparison between synthetic and conventional magnetic resonance imaging in patients with multiple sclerosis and controls. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2019; 33:549-557. [PMID: 31782035 DOI: 10.1007/s10334-019-00804-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 10/30/2019] [Accepted: 11/18/2019] [Indexed: 12/20/2022]
Abstract
OBJECTIVES Synthetic magnetic resonance imaging (SyMRI) allows to obtain different weighted-images using the multiple-dynamic multiple-echo sequence lasting 6 min. The aim is to compare quantitatively and qualitatively synthetic- and conventional MRI in patients with multiple sclerosis (MS) and controls assessing the contrast (C), the signal to noise ratio (SNR), and the contrast to noise ratio (CNR). We evaluated the lesion count and lesion-to-white matter contrast ([Formula: see text] in the MS patients. METHODS AND METHODS 51 patients underwent synthetic- and conventional MRI. Qualitative analysis was evaluated by assigning scores to all synthetic- and conventional MRI sequences by two neuroradiologists. Lesions were counted in MS patients both in the conventional- and synthetic T2-FLAIR. Regions of interest were placed in the cerebrospinal fluid, in the white- and grey matter. For the sequences were evaluated: C, CNR, and SNR. RESULTS Synthetic T2-FLAIR images are qualitatively inferior. C and CNR were significantly higher in synthetic T1W and T2W images compared to conventional images, but not for T2-FLAIR. The SNR value was always lower in synthetic images than in conventional ones. CONCLUSIONS SyMRI can be used in clinical practice because it has a similar diagnostic accuracy which reduces the scanning time compared to the conventional one. However, synthetic T2-FLAIR images need to be improved.
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Affiliation(s)
- Francesca Di Giuliano
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy.,U.O.C Diagnostic Imaging and Neuroradiology, Department of Integrated Care Processes, Fondazione PTV Policlinico "Tor Vergata", University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy
| | - Silvia Minosse
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy.
| | - Eliseo Picchi
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy.,U.O.C Diagnostic Imaging and Neuroradiology, Department of Integrated Care Processes, Fondazione PTV Policlinico "Tor Vergata", University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy
| | - Girolama Alessandra Marfia
- Multiple Sclerosis Clinical and Research Unit, Department of Systems Medicine, University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy.,Neurology Unit, Department of Neurosciences, Fondazione PTV Policlinico "Tor Vergata", University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy
| | - Valerio Da Ros
- Department of Diagnostic Imaging and Interventional Radiology, Policlinico Tor Vergata, Viale Oxford 81, 00133, Rome, Italy
| | - Massimo Muto
- Department of Neurosciences and Reproductive and Odontostomatological Sciences, University of Naples Federico II, 80100, Naples, Italy
| | - Mario Muto
- Department of Neuroradiology, A.O.R.N. Cardarelli, 80100, Naples, Italy
| | - Chiara Adriana Pistolese
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy.,U.O.C Diagnostic Imaging and Neuroradiology, Department of Integrated Care Processes, Fondazione PTV Policlinico "Tor Vergata", University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy
| | - Andrea Laghi
- Department of Surgical and Medical Sciences and Translational Medicine, Radiology Unit, "Sapienza" University of Rome, Sant'Andrea University Hospital, Via di Grottarossa, 1035-1039, 00189, Rome, Italy
| | - Francesco Garaci
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy.,U.O.C Diagnostic Imaging and Neuroradiology, Department of Integrated Care Processes, Fondazione PTV Policlinico "Tor Vergata", University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy
| | - Roberto Floris
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy.,U.O.C Diagnostic Imaging and Neuroradiology, Department of Integrated Care Processes, Fondazione PTV Policlinico "Tor Vergata", University of Rome "Tor Vergata", Viale Oxford 81, 00133, Rome, Italy
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