Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine最新文献

{"title":"Aortic Disturbed Flow Is Associated with Aortic Angle in Patients with Tetralogy of Fallot or Double-Outlet Right Ventricle.","authors":"Hideharu Oka, Kouichi Nakau, Rina Imanishi, Kazunori Fukao, Sadahiro Nakagawa, Tatsuya Suzuki, Satoru Takahashi","doi":"10.2463/mrms.mp.2024-0203","DOIUrl":"https://doi.org/10.2463/mrms.mp.2024-0203","url":null,"abstract":"<p><strong>Purpose: </strong>Aortopathy, characterized by aortic dilatation caused by cystic medial necrosis, typically develops in adulthood but has been observed at a young age in patients with tetralogy of Fallot. We hypothesized that some patients with tetralogy of Fallot or double-outlet right ventricle experience early-onset aortic disturbed flow. This study aimed to identify and analyze the causes of disturbed flow using 4D flow MRI.</p><p><strong>Methods: </strong>This study included 24 patients who underwent 4D flow MRI at our institution between January 2022 and September 2024. MRI and cardiac catheterization were performed during follow-up. 4D flow MRI was used to detect disturbed flow and investigate its underlying causes.</p><p><strong>Results: </strong>The mean age of patients with tetralogy of Fallot or double-outlet right ventricle was 12 years (range, 1 to 37 years). Of the 24 participants, 11 (46%) exhibited disturbed flow. Patients with disturbed flow had significantly higher Valsalva Z-scores (4.7 ± 3.1 vs. 2.4 ± 1.4, P = 0.013) and a significantly narrower left ventricular outflow tract-ascending aorta angle (113.5 ± 11.6 vs. 127.1 ±  6.7°, P = 0.002). Wall shear stress and energy loss were not significantly different between the 2 groups.</p><p><strong>Conclusion: </strong>Aortic disturbed flow may occur in patients with tetralogy of Fallot or double-outlet right ventricle, regardless of age, suggesting an association with the left ventricular outflow tract-ascending aorta angle. The occurrence of disturbed flow at a young age should be noted as it may contribute to the future progression of aortopathy.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144304137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utility of Thin-slice Single-shot T2-weighted MR Imaging with Deep Learning Reconstruction as a Protocol for Evaluating Pancreatic Cystic Lesions.","authors":"Kumi Ozaki, Hanae Hasegawa, Jihun Kwon, Yasutomo Katsumata, Masami Yoneyama, Shota Ishida, Takafumi Iyoda, Masataka Sakamoto, Shuuhei Aramaki, Yukichi Tanahashi, Satoshi Goshima","doi":"10.2463/mrms.mp.2025-0042","DOIUrl":"https://doi.org/10.2463/mrms.mp.2025-0042","url":null,"abstract":"<p><strong>Purpose: </strong>To assess the effects of industry-developed deep learning reconstruction with super resolution (DLR-SR) on single-shot turbo spin-echo (SshTSE) images with thickness of 2 mm with DLR (SshTSE^2mm) relative to those of images with a thickness of 5 mm with DLR (SSshTSE^5mm) in the patients with pancreatic cystic lesions.</p><p><strong>Methods: </strong>Thirty consecutive patients who underwent abdominal MRI examinations because of pancreatic cystic lesions under observation between June 2024 and July 2024 were enrolled. We qualitatively and quantitatively evaluated the image qualities of SshTSE^2mm and SshTSE^5mm with and without DLR-SR.</p><p><strong>Results: </strong>The SNRs of the pancreas, spleen, paraspinal muscle, peripancreatic fat, and pancreatic cystic lesions of SshTSE^2mm with and without DLR-SR did not decrease in compared to that of SshTSE^5mm with and without DLR-SR. There were no significant differences in contrast-to-noise ratios (CNRs) of the pancreas-to-cystic lesions and fat between 4 types of images. SshTSE^2mm with DLR-SR had the highest image quality related to pancreas edge sharpness, perceived coarseness pancreatic duct clarity, noise, artifacts, overall image quality, and diagnostic confidence of cystic lesions, followed by SshTSE^2mm without DLR-SR and SshTSE^5mm with and without DLR-SR (P  <  0.0001).</p><p><strong>Conclusions: </strong>SshTSE^2mm with DLR-SR images had better quality than the other images and did not have decreased SNRs and CNRs. The thin-slice SshTSE with DLR-SR may be feasible and clinically useful for the evaluation of patients with pancreatic cystic lesions.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144304139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of the Fast Field Echo Resembling a CT Using Restricted Echo-spacing (FRACTURE) Technique to Cranial and Facial Bone Lesions: A Feasibility Study.","authors":"Ryota Kogue, Masayuki Maeda, Seiya Kishi, Fumine Tanaka, Maki Umino, Hajime Sakuma","doi":"10.2463/mrms.ici.2025-0007","DOIUrl":"https://doi.org/10.2463/mrms.ici.2025-0007","url":null,"abstract":"<p><p>A novel imaging technique, CT-like MRI, specifically Fast Field Echo Resembling a CT Using Restricted Echo-spacing (FRACTURE), has been developed to depict bones. The purpose of this study is to evaluate the feasibility of FRACTURE MRI in cranial and facial bone lesions. Our results suggest that FRACTURE MRI can be used in addition to conventional MRI to evaluate a variety of pathologies of the cranial and facial bones.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144201193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Impact of Model-based Deep-learning Reconstruction Compared with that of Compressed Sensing-Sensitivity Encoding on the Image Quality and Precision of Cine Cardiac MR in Evaluating Left-ventricular Volume and Strain: A Study on Healthy Volunteers.","authors":"Satonori Tsuneta, Satoru Aono, Rina Kimura, Jihun Kwon, Noriyuki Fujima, Kinya Ishizaka, Noriko Nishioka, Masami Yoneyama, Fumi Kato, Kazuyuki Minowa, Kohsuke Kudo","doi":"10.2463/mrms.mp.2024-0202","DOIUrl":"https://doi.org/10.2463/mrms.mp.2024-0202","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the effect of model-based deep-learning reconstruction (DLR) compared with that of compressed sensing-sensitivity encoding (CS) on cine cardiac magnetic resonance (CMR).</p><p><strong>Methods: </strong>Cine CMR images of 10 healthy volunteers were obtained with reduction factors of 2, 4, 6, and 8 and reconstructed using CS and DLR. The visual image quality scores assessed sharpness, image noise, and artifacts. Left-ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) were manually measured. LV global circumferential strain (GCS) was automatically measured using the software. The precision of EDV, ESV, SV, EF, and GCS measurements was compared between CS and DLR using Bland-Altman analysis with full-sampling data as the gold standard.</p><p><strong>Results: </strong>Compared with CS, DLR significantly improved image quality with reduction factors of 6 and 8. The precision of EDV and ESV with a reduction factor of 8, and GCS with reduction factors of 6 and 8 measurements improved with DLR compared with CS, whereas those of SV and EF measurements were not different between DLR and CS.</p><p><strong>Conclusion: </strong>The effect of DLR on cine CMR's image quality and precision in evaluating quantitative volume and strain was equal or superior to that of CS. DLR may replace CS for cine CMR.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144201194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of the Data Pattern and Analysis Algorithm for the T2-based Water Suppression Diffusion MRImaging (T2wsup-dMRI) Technique.","authors":"Tokunori Kimura","doi":"10.2463/mrms.tn.2024-0181","DOIUrl":"https://doi.org/10.2463/mrms.tn.2024-0181","url":null,"abstract":"<p><p>We have proposed a T2-based free water suppression diffusion MRI (T2wsup-dMRI) technique to address parameter quantification issues due to cerebrospinal fluid (CSF) partial volume effects (PVEs), using a closed form (CF) algorithm. This study optimizes data patterns in (TE, b-value) space and analyzes algorithms for enhanced accuracy and precision. We simulated noise-added numerical, phantom, and brain MRI data to evaluate relative error and coefficient of variation in quantitative parameters using various data patterns and analysis algorithms (CF and least squares [LSQ] fitting). With 4 minimum data points applied to healthy brain tissue with T2 < 100 ms, the CF algorithm with water volume separation was optimal. For more than 4 points, a smaller b-value with shorter TE combined with 2d single- and bi-exponential LSQ fitting provided the best results. The T2wsup-dMRI technique reduces CSF-PVE artifacts in tissue-specific parameter quantification, enhancing approaches for patient needs, data acquisition, and computing costs.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144145304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Standardizing Ultrafast Dynamic Contrast-enhanced MR Imaging: Considerations for Spatial Resolution and Imaging Techniques.","authors":"Naoko Mori","doi":"10.2463/mrms.lte.2025-0026","DOIUrl":"https://doi.org/10.2463/mrms.lte.2025-0026","url":null,"abstract":"","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144121801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Are Diffusion Models Effective Good Feature Extractors for MRI Discriminative Tasks?","authors":"Binghua Li, Zhe Sun, Chao Li, Koji Kamagata, Christina Andica, Wataru Uchida, Kaito Takabayashi, Sen Guo, Rui Zou, Shigeki Aoki, Toshihisa Tanaka, Qibin Zhao","doi":"10.2463/mrms.mp.2024-0206","DOIUrl":"https://doi.org/10.2463/mrms.mp.2024-0206","url":null,"abstract":"<p><strong>Purpose: </strong>Diffusion models (DMs) excel in pixel-level and spatial tasks and are proven feature extractors for 2D image discriminative tasks when pretrained. However, their capabilities in 3D MRI discriminative tasks remain largely untapped. This study seeks to assess the effectiveness of DMs in this underexplored area.</p><p><strong>Methods: </strong>We use 59830 T1-weighted MR images (T1WIs) from the extensive, yet unlabeled, UK Biobank dataset. Additionally, we apply 369 T1WIs from the BraTS2020 dataset specifically for brain tumor classification, and 421 T1WIs from the ADNI1 dataset for the diagnosis of Alzheimer's disease. Firstly, a high-performing denoising diffusion probabilistic model (DDPM) with a U-Net backbone is pretrained on the UK Biobank, then fine-tuned on the BraTS2020 and ADNI1 datasets. Afterward, we assess its feature representation capabilities for discriminative tasks using linear probes. Finally, we accordingly introduce a novel fusion module, named CATS, that enhances the U-Net representations, thereby improving performance on discriminative tasks.</p><p><strong>Results: </strong>Our DDPM produces synthetic images of high quality that match the distribution of the raw datasets. Subsequent analysis reveals that DDPM features extracted from middle blocks and smaller timesteps are of high quality. Leveraging these features, the CATS module, with just 1.7M additional parameters, achieved average classification scores of 0.7704 and 0.9217 on the BraTS2020 and ADNI1 datasets, demonstrating competitive performance with that of the representations extracted from the transferred DDPM model, as well as the 33.23M parameters ResNet18 trained from scratch.</p><p><strong>Conclusion: </strong>We have found that pretraining a DM on a large-scale dataset and then fine-tuning it on limited data from discriminative datasets is a viable approach for MRI data. With these well-performing DMs, we show that they excel not just in generation tasks but also as feature extractors when combined with our proposed CATS module.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144059095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impaired Glymphatic Function in Diffuse Axonal Injury: Evaluation Using the Diffusion Tensor Imaging Analysis Along the Perivascular Space (DTI-ALPS) Method.","authors":"Sung Hyun An, Miran Han, Woo Sang Jung, Jin Wook Choi, Eun Ju Ha, Sun-Won Park, Jung Hyo Rhim, Mira Han, Jung Hyun Park","doi":"10.2463/mrms.mp.2024-0088","DOIUrl":"https://doi.org/10.2463/mrms.mp.2024-0088","url":null,"abstract":"<p><strong>Purpose: </strong>Glymphatic system impairment has been suggested in previous animal and human studies regarding traumatic brain injury (TBI). Diffuse axonal injury (DAI) is an important pathological feature of TBI and is frequently diagnosed in patients with moderate to severe TBI. This study evaluated the glymphatic system function in patients with DAI using diffusion tensor imaging analysis along the perivascular space (DTI-ALPS), a non-invasive technique.</p><p><strong>Methods: </strong>A total of 162 patients with TBI, including 84 with DAI and 78 without DAI, underwent MRI with DTI within 6 months of the date of injury. The ALPS index was calculated to assess the glymphatic system activity and compared between patients with and without DAI. Analysis of covariance (ANCOVA) was used to compare the ALPS index between patients with DAI grades 1, 2, and 3. Correlation analysis was performed between the ALPS index, DAI grade, and Glasgow Coma Scale (GCS) score.</p><p><strong>Results: </strong>Patients with DAI (1.29 ± 0.17) had a significantly lower ALPS index than those without DAI (1.42 ± 0.19, P < 0.001). The ALPS index differed significantly between patients with different DAI grades (ANCOVA, P < 0.001). The ALPS index and DAI grades were negatively correlated (r =-0.47, P < 0.001). The ALPS index and GCS scores showed a weak positive correlation (r = 0.174, P = 0.027).</p><p><strong>Conclusions: </strong>Patients with DAI have a lower ALPS index, indicating impaired glymphatic system activity, which is more severe in patients with a higher DAI grade. These findings broaden the understanding of the pathophysiology of DAI and help predict patients' prognoses and recovery trends.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144004339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of the Magnetization Transfer Effect on T1 Measurements in Quantitative MR Imaging: Comparison of the Two-dimensional Multidynamic Multiecho (2D-MDME) and Three-dimensional Quantification Using an Interleaved Look-Locker Acquisition Sequence (3D-QALAS) Protocols on Two Systems.","authors":"Ryoichi Kose, Katsumi Kose, Yasuhiko Terada, Daiki Tamada","doi":"10.2463/mrms.tn.2024-0163","DOIUrl":"https://doi.org/10.2463/mrms.tn.2024-0163","url":null,"abstract":"<p><p>Multiparametric quantitative MRI (MP-qMRI) methods, which measure multiple relaxation times simultaneously, are becoming into practical tools, but the relationship between different MP-qMRI methods has not been clarified. In particular, since 2D multidynamic multiple-echo (2D-MDME) was provided by multiple major MRI vendors, many patient studies have been reported, but its relationship with 3D-QALAS (3D-QuAntification using an interleaved Look-Locker Acquisition Sequence with T₂ preparation pulse), which is expected to be its 3D version successor, is unknown. In this study, we implemented 2D-MDME and 3D-QALAS on an originally designed 1.5T and a clinical 3T MRI systems, and measured relaxation times of phantoms, focusing on the effect of magnetization transfer (MT) effect on T₁ measurements. As a result, in 2D-MDME, T₁ shortening effects of around 20%-35% was observed due to the MT effect, and in 3D-QALAS, no effect of the MT effect on the T₁ measurements was observed. Therefore, we concluded that the MT effect needs to be considered when comparing MP-qMRI methods in clinical studies.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144001146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Added Value of Sodium MR Imaging and Proton MR Spectroscopy to Conventional MR Imaging for a Better Characterization of the Ischemic Stroke: A Narrative Review.","authors":"Maëva Cotinat, Emmanuelle Robinet, Noëlle Messaoudi, Laurent Suissa, Emilie Doche, Maxime Guye, Laurent Bensoussan, Wafaa Zaaraoui, Jean-Philippe Ranjeva","doi":"10.2463/mrms.rev.2025-0002","DOIUrl":"https://doi.org/10.2463/mrms.rev.2025-0002","url":null,"abstract":"<p><p>Stroke is a major cause of disability and death in adults worldwide. In clinical setting, time efficient MRI protocols including diffusion weighted images, fluid attenuated inversion recovery, fast T2*-weighted images and MR angiography aim to establish ischemic stroke diagnosis, visualize vessel occlusion and determine the extent of ischemia damage distinguishing between the salvageable ischemic penumbra and the infarct core. Thus, MRI plays a pivotal role in diagnosis, treatment decision-making, and prognostic assessment, although prediction based on these elements remains limited and can be improved. We reviewed the added-values of alternative MRI methods such as sodium(²³Na) MRI and ¹H MR spectroscopic imaging that open new temporal and pathophysiological windows on ionic dys-homeostasis and metabolism alteration in the context of ischemic stroke and reperfusion. Insights on the timeline of the cellular events accessible using these alternative methods and perspectives to improve clinical outcome prediction of ischemic stroke patients are discussed.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144013546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}