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

{"title":"Hidden Pitfall in Multiple Sclerosis Imaging: How Standard Susceptibility-Weighted Imaging (SWI) May Miss Paramagnetic Rim Lesions.","authors":"Yuki Sonoda, Akifumi Hagiwara, Yuji Tomizawa, Yasunobu Hoshino, Junko Kikuta, Hideo Kawasaki, Moto Nakaya, Satoru Kamio, Ryutaro Yano, Hiroshi Kusahara, Taku Hatano, Koji Kamagata, Shigeki Aoki","doi":"10.2463/mrms.bc.2025-0073","DOIUrl":"10.2463/mrms.bc.2025-0073","url":null,"abstract":"<p><p>This case report shows that paramagnetic rim lesions (PRLs), markers of chronic active lesions in multiple sclerosis, vary in visibility depending on scan-parameters of susceptibility-weighted imaging (SWI). Routine SWI for microbleed detection with low flip angle (FA) failed to depict PRLs, while longer TE and higher FA improved visibility. Phase images consistently visualized PRLs. These findings underscore the need to optimize TE and FA, as suboptimal SWI settings may hinder PRL detection.</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":3.2,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13041246/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144823557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interpretation of Diffusion MR Imaging Data Using Non-negative Least Squares (NNLS).","authors":"Koichi Oshio, Katsuhiro Sano, Hiroshi Kusahara, Koji Kamagata, Shigeki Aoki","doi":"10.2463/mrms.tn.2024-0210","DOIUrl":"10.2463/mrms.tn.2024-0210","url":null,"abstract":"<p><p>The interpretation of abdominal diffusion images remains difficult because different types of tissue coexist within each voxel. In this study, we estimated the distribution of the diffusion coefficient (D) within each voxel using non-negative least squares from diffusion-weighted images with multiple b-values. Additionally, a method for visualizing the results as a set of images representing the D ranges was developed. This method was tested on healthy volunteers.</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":3.2,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13041241/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simple Frame-based Approach for MR Imaging-guided Abdominal Biopsy: Preliminary Evaluation in a Phantom Model.","authors":"Anastasia Antoniou, Nikolas Evripidou, Leonidas Georgiou, Antreas Chrysanthou, Antonis Christofi, Cleanthis Ioannides, Liyang Yu, Christakis Damianou","doi":"10.2463/mrms.mp.2024-0187","DOIUrl":"10.2463/mrms.mp.2024-0187","url":null,"abstract":"<p><strong>Purpose: </strong>Although automation offers several benefits in MRI-guided abdominal biopsies, the conventional surgeon-centric approach continues to be the preferred technique. This study presents an ergonomic biopsy device aimed at streamlining the MRI-guided abdominal biopsy process while preserving operator control.</p><p><strong>Methods: </strong>A dedicated belt was designed with adjustable straps to accommodate patients of varying sizes. A biopsy frame with 2 manual degrees of freedom was movably affixed to the belt, allowing for adjustable positioning across the patient's circumference to align with the region of interest. Preliminary testing was performed on an abdominal biopsy phantom with 2 embedded 7-mm tumor mimics in a 3T MRI scanner. Needle guide registration in MRI coordinates was achieved by attaching a water-filled syringe to the guide, which was then navigated to align with each target using a straightforward method involving the acquisition and fusion of parallel images. A clinically relevant half-Fourier acquisition single-shot turbo spin echo sequence was used for both the initial alignment and for intermittent imaging during the stepwise advancement of a metallic clinical needle toward the target.</p><p><strong>Results: </strong>The device was easy to use, even for a non-experienced operator. The employed methodology enabled straightforward calculation of the 2D path for aligning the syringe with the target. Alignment accuracy was within the submillimeter range. The employed sequence was robust against susceptibility artifacts, enabling precise guidance, with the accuracy of tumor puncture ultimately dependent on the operator.</p><p><strong>Conclusion: </strong>The proposed biopsy method has the potential to enhance stability and accuracy over traditional techniques, while being more ergonomic and cost-effective than advanced robotic systems, also maintaining human control. Extensive preclinical and clinical evaluation is needed to fully assess effectiveness and safety.</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":3.2,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13041250/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145234775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of MR Imaging of High-grade Serous Carcinomas with and without Homologous Recombination-deficiency.","authors":"Tsukasa Saida, Ayumi Shikama, Miki Yoshida, Taishi Amano, Toshitaka Ishiguro, Masafumi Sakai, Sodai Hoshiai, Toyomi Satoh, Takahito Nakajima","doi":"10.2463/mrms.mp.2025-0071","DOIUrl":"10.2463/mrms.mp.2025-0071","url":null,"abstract":"<p><strong>Purpose: </strong>MRI findings of high-grade serous carcinoma (HGSC) with and without homologous recombination deficiency (HRD) were compared to explore the feasibility of using MRI as a genetic predictor.</p><p><strong>Methods: </strong>We retrospectively reviewed MRI data from HRD-positive and HRD-negative HGSC and evaluated tumor size, appearance, apparent diffusion coefficient (ADC), time-intensity curve, and several dynamic contrast-enhanced curve descriptors. Age, primary site, tumor stage, bilaterality, presence of lymph node metastasis, presence of peritoneal metastasis, and tumor marker levels were also compared.</p><p><strong>Results: </strong>Forty-eight patients with HRD-positive HGSC (17 patients with BRCA1 variant, 9 patients with BRCA2 variant, and 22 without BRCA variants) and 18 patients with HRD-negative HGSC were included. The HRD-negative patients' mean age was 67 years, which was significantly higher than that of the HRDpositive patients (60 years, P = 0.011). High-risk time-intensity curve (TIC) patterns were more common in HRD-negative tumors (94%) than in HRD-positive tumors (63%; P = 0.047). Tumors without HRD exhibited significantly higher wash-in rates (P = 0.023). Additionally, unresectable lymph node metastases were significantly more frequent in HRD-negative patients (P = 0.013). No significant differences were observed in the other evaluated factors.</p><p><strong>Conclusion: </strong>The comparison between HGSC with and without HRD revealed that HGSC without HRD was significantly associated with older age, a higher likelihood of exhibiting a high-risk TIC pattern, a higher wash-in rate, and a higher frequency of unresectable lymph node metastasis.</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":3.2,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13041242/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145234711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ocular Solute Movement Direction and Intracranial Clearance via Vitreous Gadolinium-based Contrast Agent MR Imaging: Potential as a Novel Biomarker for Glymphatic Dysfunction.","authors":"Shinji Naganawa, Rintaro Ito, Mariko Kawamura, Toshiaki Taoka, Tadao Yoshida, Michihiko Sone","doi":"10.2463/mrms.mp.2025-0127","DOIUrl":"10.2463/mrms.mp.2025-0127","url":null,"abstract":"<p><strong>Purpose: </strong>The ocular and brain glymphatic systems may share common physiological pathways. We hypothesized that the anteroposterior movement of gadolinium-based contrast agent (GBCA) that has leaked into the vitreous could serve as a biomarker for brain glymphatic function. This study aimed to retrospectively investigate the association between the intravitreal GBCA distribution on MRI and recently proposed imaging markers of impaired brain waste clearance.</p><p><strong>Methods: </strong>We analyzed 156 eyes from 78 adult participants who underwent 3T MRI 4 hr after standard-dose GBCA administration. On 3D-real IR images, we calculated a \"contrast shift index\" (the signal difference between anterior and posterior vitreous volumes of interest: VOIa-VOIp) to quantify the anteroposterior GBCA distribution. The primary outcome was a composite endpoint of positivity for either putative meningeal lymphatics at the posterior sigmoid sinus (PML-PSS) or enhanced basal ganglia perivascular spaces (PVS-BG). Multivariable logistic regression with cluster-robust inference was used to assess predictors, including the contrast shift index, mean vitreous contrast distribution, age, sex, and axial length of the eye.</p><p><strong>Results: </strong>A positive contrast shift index, indicating preferential anterior GBCA distribution, was significantly and independently associated with the composite outcome of impaired brain clearance (P = 0.006). Age (P <0.001) and male sex (P = 0.009) were also independent predictors. A predictive model incorporating these factors demonstrated high discrimination, with an area under the receiver operating characteristic curve (AUC) of 0.872. Axial length of the eye and mean vitreous contrast distribution were not significant independent predictors.</p><p><strong>Conclusion: </strong>The anteroposterior distribution of GBCA in the vitreous is a novel, non-invasive imaging biomarker associated with impaired brain clearance function. This \"contrast shift index\" may reflect systemic glymphatic dysregulation common to both the eye and brain, offering a new avenue for assessing neurodegenerative risk.</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":3.2,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13041247/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145188047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perfusion Signal Analysis Using Multi-pulsed Arterial Spin Labeling (mPASL) with Multiple Post-labeling Delays: Phantom Validation and Application to the Human Foot.","authors":"Vadim Malis, Yoshiki Kuwatsuru, Mitsue Miyazaki","doi":"10.2463/mrms.mp.2025-0047","DOIUrl":"10.2463/mrms.mp.2025-0047","url":null,"abstract":"<p><strong>Purpose: </strong>This study aims to extend the general kinetic model (GKM) for perfusion signal analysis using multi-pulsed arterial spin labeling (mPASL) acquisitions with multiple post-labeling delays (mPLD). The approach aims to improve accuracy and gain potential for broader experimental and clinical applications.</p><p><strong>Methods: </strong>The magnetization vector evolution of the mPASL technique was analyzed using sequence diagrams and numerical simulation, supplemented by static phantom experiments. The GKM was adapted to support different configurations of mPASL tagging pulses in \"dark\" and \"bright\" methods. The proposed approach was validated on a constant-flow phantom and applied to in-vivo foot perfusion measurements in a cohort of 5 healthy subjects.</p><p><strong>Results: </strong>Simulations showed that the ratio between \"dark\" and \"bright\" mPASL methods is determined by fluid T₁ relaxation time, the number of selective pulses, and labeling efficiency. Experiments with a constant-flow phantom demonstrated that GKM with mPASL enables semi-quantitative perfusion analysis, providing high-temporal-resolution perfusion curves. Estimated perfusion coefficients of constant flow phantom were consistent across acquisitions (5.1% variation), confirming the robustness of the GKM extension for mPASL with multiple post-labeling delays. However, in-vivo results deviated from simulation and constant flow experiments, highlighting potential physiological complexities, and model limitations.</p><p><strong>Conclusion: </strong>Extending the GKM to mPASL acquisitions demonstrates reliable performance under controlled constant flow conditions. Phantom experiments confirmed the accuracy of the approach, while in-vivo measurements in feet revealed deviations from simulation and constant flow results, suggesting the need to account for physiological factors and potential model extension due to pulsatile flow.</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":3.2,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13041248/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144994937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential to Avoid Invasive Procedures for Atypical Focal Nodular Hyperplasia (FNH) and FNH-like Lesions Based on MR Findings.","authors":"Hanae Hasegawa, Kumi Ozaki, Kenichi Harada, Yukichi Tanahashi, Satoshi Goshima","doi":"10.2463/mrms.mp.2025-0070","DOIUrl":"10.2463/mrms.mp.2025-0070","url":null,"abstract":"<p><strong>Purpose: </strong>To identify the imaging characteristics of rare, histopathologically confirmed focal nodular hyperplasia (FNH) and FNH-like lesions (FNH/FNH-like lesions) and determine whether invasive procedures could have been avoided by comprehensive MRI review.</p><p><strong>Methods: </strong>We retrospectively enrolled patients with pathologically confirmed FNH/FNH-like lesions between January 2011 and December 2023. These cases underwent biopsy or resection due to their atypical hepatobiliary phase appearance. Six patients with hepatocellular carcinoma (HCC) were included from a separate cohort for comparison. Gadoxetic acid-enhanced MRI findings were qualitatively evaluated. Apparent diffusion coefficient (ADC) values and enhancement during the hepatobiliary phase were quantitatively assessed, and the relative enhancement ratio (RER) to liver parenchyma and intrahepatic vessel (RERv) was calculated. Organic anion transporting polypeptides (OATP)1B3 expression was confirmed histopathologically.</p><p><strong>Results: </strong>Five patients with FNH/FNH-like lesions and 6 patients with HCC were evaluated. The non-contrast MRI findings were non-specific for both groups. All 5 FNH/FNH-like lesions displayed non-rim arterial phase hyperenhancement (APHE) without washout during dynamic contrast study with ADC values of 1.162 ± 0.124 × 10^-3mm²/sec (mean ± standard deviation). Whereas all 6 HCCs displayed non-rim APHE and washout with ADC values of 0.923 ± 0.138 × 10^-3mm²/sec. During the hepatobiliary phase, all 5 FNH/FNH-like lesions were hypointense to the liver but hyperintense to intrahepatic vessels, with RER and RERv ≥ 0.90, indicating preserved gadoxetic acid uptake. OATP1B3 membrane expression was confirmed. By contrast, 5 HCCs were hypointense to both the liver and vessels, with RER and RERv < 0.90 and no OATP1B3 expression.</p><p><strong>Conclusion: </strong>FNH/FNH-like lesions with hepatobiliary phase hypointensity, the characteristic finding of hyperintensity relative to intrahepatic vessels distinguished them from similarly presenting HCCs. Careful evaluation of this specific imaging feature might have potentially avoided the need for invasive treatment or biopsy in these diagnostically challenging cases.</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":3.2,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13041245/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145254211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Errata.","authors":"","doi":"10.2463/mrms.err.2026-1000","DOIUrl":"https://doi.org/10.2463/mrms.err.2026-1000","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":"25 2","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147694597","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":"Hyperintense Signals in Cerebral Blood Flow Maps of Mice Acquired with Pseudo-continuous Arterial Spin Labeling MR Imaging.","authors":"Xiuli Yang, Yuguo Li, Adnan Bibic, Zhiliang Wei","doi":"10.2463/mrms.mp.2026-0023","DOIUrl":"10.2463/mrms.mp.2026-0023","url":null,"abstract":"<p><strong>Purpose: </strong>Pseudo-continuous arterial spin labeling (pCASL) MRI is a widely used, noninvasive, contrast-agent-free technique for measuring cerebral blood flow (CBF) and assessing vascular dysfunction across diverse clinical settings and murine disease models. In practice, arterial-transit artifacts that generate hyperintense signal in CBF maps warrant careful consideration. While these effects are well characterized in humans, they are less well understood in mice owing to the marked interspecies physiological differences.</p><p><strong>Methods: </strong>To address this knowledge gap, we systematically characterized pCASL hyperintense signal as a function of post-labeling delay (PLD) and crusher-gradient strength in mice. Numerical simulations were also performed to validate the experimental findings.</p><p><strong>Results: </strong>We found that hyperintense signals in mice extend to arteries, major veins, and ventricular structures. Such a pattern was different from human pCASL images, where hyperintense signals are predominantly present in arteries. Statistical analyses supported a PLD of 500 milliseconds as a pragmatic balance between detection sensitivity and suppression of vascular contamination. Additional experiments and numerical simulations showed that, within the tested range, stronger crusher gradients provided little extra vascular suppression-primarily because large vessel calibers relative to small voxels limit intravoxel phase dispersion.</p><p><strong>Conclusion: </strong>These findings refine the interpretation of murine pCASL signals and facilitate more accurate perfusion imaging in preclinical pathophysiological studies.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":"25 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13683968/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148809142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure-preserving Image-quality Enhancement for 3D Synthetic FLAIR Using a 3D U-Net with Content and Style Losses.","authors":"Satoru Kamio, Akifumi Hagiwara, Yujiro Otsuka, Moto Nakaya, Reina Hosoi, Yasunobu Hoshino, Yuji Tomizawa, Yuika Tsukamoto, Naohisa Hara, Junko Kikuta, Christina Andica, Toshiaki Akashi, Akihiko Wada, Hiroshi Kusahara, Ryutaro Yano, Taku Hatano, Osamu Abe, Koji Kamagata","doi":"10.2463/mrms.mp.2026-0101","DOIUrl":"10.2463/mrms.mp.2026-0101","url":null,"abstract":"<p><strong>Purpose: </strong>Synthetic MRI can generate multiple contrasts from a single acquisition, yet synthetic fluid-attenuated inversion recovery (FLAIR) generally shows lower quality than conventional FLAIR. We aimed to improve 3D synthetic FLAIR image quality using deep learning, without losing the scan-time advantage of synthetic MRI.</p><p><strong>Methods: </strong>We studied 55 adults with inflammatory demyelinating diseases who underwent 3T MRI. For each participant, five 3D quantification using an interleaved Look-Locker acquisition sequence with T2 preparation (3D-QALAS) source images and a conventional 3D-FLAIR image were acquired, and a synthetic FLAIR image was generated from the 3D-QALAS data. We trained a deep learning model in which a 3D U-shaped convolutional network (U-Net)-based attention network predicted voxel-wise weights for generating FLAIR images from the five 3D-QALAS source images, using conventional 3D-FLAIR images as the reference. The model was trained with a combined loss function of mean squared error, content loss, and style loss. Agreement with the reference was assessed using image similarity and error metrics, lesion overlap using the Dice similarity coefficient, and overall image quality and focal lesion visibility using blinded radiologist ratings. Synthetic FLAIR and the deep learning-generated FLAIR images were compared using 2-sided Wilcoxon signed-rank tests; P < 0.05 was considered statistically significant.</p><p><strong>Results: </strong>The deep learning-generated FLAIR images showed significantly higher agreement with the reference image than synthetic FLAIR images (all P < 0.001). Lesion overlap was higher with the deep learning-generated FLAIR images (median [interquartile range]: 0.642 [0.528-0.711] versus 0.487 [0.344-0.641]). Qualitatively, the deep learning-generated FLAIR images improved overall image quality and focal lesion visibility, but reader scores remained lower than those for the reference conventional 3D-FLAIR images (all P < 0.001).</p><p><strong>Conclusion: </strong>A deep learning-based approach applied to five 3D-QALAS source images improved the image quality of 3D synthetic FLAIR. These improvements may increase the clinical utility of 3D synthetic MRI for neuroradiologic assessment.</p>","PeriodicalId":94126,"journal":{"name":"Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine","volume":"25 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13683563/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148665393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}