Magnetic Resonance Materials in Physics, Biology and Medicine最新文献

{"title":"Improved diffusion tensor parametric maps in the brain from reduced-direction acquisitions using a deep learning approach.","authors":"Nontharat Tucksinapinunchai, Ratthaporn Boonsuth, Artit Rodkong, Pongpun Saokhieo, Diana E Peragine, Malvina N Skorska, Lindsey T Thurston, Daisy Z Hu, Taweewat Supindham, Oranitcha Kaewthip, Kittichai Wantanajittikul, Suwit Saekho, Suwat Chariyalertsak, Salita Angkurawaranon, Doug P VanderLaan, Uten Yarach","doi":"10.1007/s10334-026-01431-x","DOIUrl":"https://doi.org/10.1007/s10334-026-01431-x","url":null,"abstract":"<p><strong>Objectives: </strong>This study implements and evaluates a deep learning approach to enhance FA, MD, AD, and RD maps derived from 16-direction DTI to approximate corresponding maps derived from 32-direction DTI, with the aim of reducing acquisition time while maintaining quantitative accuracy.</p><p><strong>Materials and methods: </strong>A modified 8-layer 3D convolutional neural network was trained using scalar DTI-derived maps from 16-direction acquisitions as input and corresponding 32-direction maps as reference targets. Model performance was evaluated on an independently acquired evaluation cohort (n=33) using PSNR, %NRMSE, SSIM, Bland-Altman analysis, and tract-based spatial statistics (TBSS), with BM4D and AONLM as comparators.</p><p><strong>Results: </strong>The DL model reduced noise and improved PSNR, %NRMSE, and SSIM compared with raw ND16, BM4D, and AONLM (p < 0.05). DL-derived FA, MD, and AD showed the smallest deviations from the ND32 reference among the evaluated methods, although statistically significant mean differences remained. TBSS showed localized differences for FA and AD, but no significant differences for MD or RD (p > 0.05).</p><p><strong>Discussion: </strong>The proposed map-domain DL approach improved scalar DTI-derived maps from 16-direction acquisitions while reducing diffusion acquisition time by approximately 1.8-fold. The findings demonstrate improved agreement with 32-direction reference maps, while remaining quantitative differences and generalizability require further validation.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149195159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of different pre-processing methods combined with combat harmonization on the reproducibility of radiomics features in healthy human brain MRI.","authors":"Lihua Chen, Bowen Zheng, Weixiong Zeng, Yijun Lv, Haijian Zhong, Genggeng Qin","doi":"10.1007/s10334-026-01426-8","DOIUrl":"https://doi.org/10.1007/s10334-026-01426-8","url":null,"abstract":"<p><strong>Objective: </strong>To explore the effect of different pre-processing methods combined with ComBat harmonization on improving the stability of MRI radiomic features in healthy human brains.</p><p><strong>Methods: </strong>T1FLAIR and T2W scans from 416 healthy subjects across four MRI systems underwent seven pipelines (Original, N4, Z-Score, DTN, Nyul, WhiteStripe, RAVEL). SynthSeg segmented white/gray matter for 93 IBSI radiomic features. Stability was quantified via covariate-adjusted standardized scanner effect (d = β_scanner/σ_res, |d|< 0.2) with 95% bootstrap CIs, supplemented by PCA and LOOCV AUC. Friedman and post-hoc McNemar tests with Bonferroni correction compared pipelines. FDR-corrected partial correlations assessed retention of significant age and sex associations after ComBat.</p><p><strong>Results: </strong>Raw data exhibited extremely low stability with substantial scanner-induced effects, while scanner classification AUC was close to 1.0. ComBat harmonization significantly improved stability across all pipelines and reduced AUC to near 0.5. Within this dataset, DTN_ComBat demonstrated consistently high stability; pairwise statistical comparisons indicated it showed more favourable stability performance relative to most other pipelines for the majority of tested contrasts, with stable proportions exceeding 90% across all sequences and tissues, and retained 75.0-100.0% of statistically significant age and sex-related associations.</p><p><strong>Conclusion: </strong>Unprocessed brain MRI radiomic features exhibit poor cross‑scanner stability. Within this dataset, ComBat effectively reduces scanner‑related feature‑distribution differences, while preserving most statistically‑significant age and sex‑related associations. Among tested pre-processing pipelines, DTN_ComBat showed comparatively favourable performance under the present healthy‑brain MRI scanner‑protocol configurations.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149182577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phantom-based synthetic renal PCASL data generation for overcoming data scarcity and enhancing deep learning-based segmentation.","authors":"Anne Oyarzun-Domeño, Rebeca Echeverria-Chasco, María A Fernández-Seara, Paloma L Martin-Moreno, Nuria Garcia-Fernandez, Gorka Bastarrika, Arantxa Villanueva, Frank G Zöllner","doi":"10.1007/s10334-026-01416-w","DOIUrl":"https://doi.org/10.1007/s10334-026-01416-w","url":null,"abstract":"<p><strong>Objectives: </strong>We hypothesize that a 2D CycleGAN framework can generate anatomically realistic synthetic renal PCASL images from phantom to overcome data scarcity and improve deep learning-based segmentation models.</p><p><strong>Materials and methods: </strong>A CycleGAN was implemented for style transfer from XCAT phantoms to PCASL. Datasets included 16 transplanted (TK) and 14 healthy (HK) subjects (3T Siemens Skyra). The synthetic dataset was used both to fine-tune existing models and to enable multi-class segmentation (cortex/medulla) in real images via a model trained exclusively on synthetic data, addressing the lack of labels.</p><p><strong>Result: </strong>In HK, the mixed model (real + synthetic data) significantly improved segmentation (mean DSC increase:, p < 0.05). For isolated left HK, the synthetic-only model achieved the highest gain (p < 0.001). In TK, synthetic data alone was less effective (p > 0.05), but the mixed model maintained baseline performance (p < 0.05). Furthermore, training the Mask R-CNN exclusively on synthetic data enabled successful segmentation of the cortex (DSC: 0.659) and medulla in real images.</p><p><strong>Discussion: </strong>Synthetic data enhances generalization and enables complex compartment segmentation. Our results demonstrate that GAN-based data augmentation significantly enhances segmentation in PCASL imaging, providing a robust and scalable solution for low-resource clinical settings.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149128040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility of angiographic imaging using fast 3D Magnetic Resonance Spin TomogrAphy in Time-domain (MR-STAT).","authors":"Martin Bastiaan Schilder, Edwin Versteeg, Stefano Mandija, Oscar van der Heide, Fei Xu, Jan Willem Dankbaar, Mervyn Driek Ingmar Vergouwen, Ynte Marije Ruigrok, Irene van der Schaaf, Cornelis Antonius Theodorus van den Berg, Alessandro Sbrizzi","doi":"10.1007/s10334-026-01425-9","DOIUrl":"https://doi.org/10.1007/s10334-026-01425-9","url":null,"abstract":"<p><strong>Objective: </strong>To investigate how angiographic information can be obtained from proton density (PD) maps reconstructed with a fast 3D Magnetic Resonance Spin TomogrAphy in Time-domain (MR-STAT) protocol, focusing on intracranial vessels and aneurysms in a clinically relevant population.</p><p><strong>Materials and methods: </strong>This proof-of-concept study consisted of two experiments. First, a healthy volunteer underwent MR-STAT with selective and non-selective excitation to investigate the origin of elevated effective proton density in arteries. Second, ten patients with intracranial aneurysms underwent 3D MR-STAT and time-of-flight MR angiography (TOF MRA). Two neuroradiologists independently assessed vessel visibility, image quality, and aneurysm size. Intraclass correlation coefficients (ICC) were computed for aneurysm size measurements.</p><p><strong>Results: </strong>Selective excitation amplified inflow effects and yielded increased artery-tissue contrast in PD maps. Major intracranial arteries were visible in all clinical MR-STAT angiographic datasets. Nine out of ten MR-STAT angiographies were rated as at least diagnostically acceptable. Aneurysm measurements showed strong agreement between conventional and MR-STAT angiographic modalities (ICC=0.86/ICC=0.71) and high inter-rater reliability (ICC=0.90/ICC=0.92).</p><p><strong>Discussion: </strong>MR-STAT PD maps enable angiographic visualization as an intrinsic component of a single fast quantitative acquisition, demonstrating technical feasibility for vessel depiction. Future work should focus on optimizing MR-STAT acquisition strategies to improve vessel conspicuity and broader clinical validation.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149111657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variable flip angle T1 mapping for quantitative liver imaging at 0.55 T.","authors":"Majd Helo, Marcel Dominik Nickel, Thomas Küstner","doi":"10.1007/s10334-026-01424-w","DOIUrl":"https://doi.org/10.1007/s10334-026-01424-w","url":null,"abstract":"<p><strong>Purpose: </strong>Investigating the feasibility of variable flip angle (VFA) T₁ mapping for quantitative liver imaging at 0.55 T and evaluating the impact of RF spoiling correction and deep learning-based (DL) reconstruction on accuracy.</p><p><strong>Methods: </strong>A VFA protocol was developed and combined with DL reconstruction to improve quantitative robustness at 0.55 T. Phantom experiments validated T₁ estimates against multi-TI inversion-recovery spin-echo reference measurements. Bloch simulations characterized RF spoiling-induced bias and derived 0.55 T-specific calibration coefficients. Twelve healthy subjects were scanned to assess field-strength-dependent effects of B₁⁺ inhomogeneity.</p><p><strong>Results: </strong>In vivo, DL reconstruction reduced noise-related variability of voxel-wise hepatic T₁ estimates compared to conventional reconstructions in the same subject. At 0.55 T, B₁⁺ maps showed the highest transmit homogeneity, with liver flip angle variation of 98.2 ± 2.9%, compared with 94.6 ± 7.4% at 1.5 T and 100.7 ± 9.8% at 3 T. Accordingly, B₁⁺ correction had minimal impact on hepatic T₁ distributions at 0.55 T, whereas more pronounced effects were observed at higher field strengths. Phantom experiments demonstrated improved agreement of VFA-derived T₁ values with the IR-SE reference after 0.55 T-specific RF spoiling correction, supporting the accuracy of the corrected VFA approach. Bland-Altman analysis confirmed that RF spoiling correction had a greater impact on phantom T₁ accuracy than B₁⁺ correction.</p><p><strong>Conclusion: </strong>At 0.55 T, RF spoiling and reconstruction strategies are the main determinants of quantitative accuracy, while transmit field inhomogeneity plays a minor role. Combined RF spoiling correction and DL reconstruction enables robust VFA T₁ mapping without B₁⁺ correction. Reduced low-field T₁ values improve VFA model conditioning and reduce sensitivity to flip angle deviations, supporting VFA-based T₁ mapping for low-field MRI.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149008766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating boost diffusion sampling for improved abdominal imaging using prototype slice-specific shimming method.","authors":"Wenwen Fan, Qinglei Shi, Peng Wang, Haolin Qin, Wenbo Cao, Fangqin Gao, Stemmer Alto, Sijie Hu, Lijuan Wan, Peihua Wu, Tongsuo Lu, Yu Lang, Renzhi Wang, Hongmei Zhang","doi":"10.1007/s10334-026-01418-8","DOIUrl":"https://doi.org/10.1007/s10334-026-01418-8","url":null,"abstract":"<p><strong>Object: </strong>To determine whether prototype integrated slice-specific shimming (iShim) diffusion-weighted imaging (DWI) combined with Boost diffusion sampling improves image quality and diagnostic performance for focal liver lesions compared with conventional DWI and alternative iShim sampling schemes.</p><p><strong>Materials and methods: </strong>Eighty-five patients with focal liver lesions underwent 3T MRI with conventional DWI and iShim-DWI using Boost, flow-compensated (FC), monopolar (Mono), FC with five lobes (FC5), and stimulated echo acquisition mode (Steam) sampling at b-values of 0 and 1000 s/mm². Two radiologists independently scored six image-quality features. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) were measured. Interreader agreement, between-sequence differences, ADC correlations and agreement, and diagnostic performance for differentiating benign from malignant lesions were assessed.</p><p><strong>Results: </strong>Boost iShim-DWI yielded significantly better artifact, diagnostic-confidence, and total-image-quality scores than all other sequences (p < 0.05) and achieved the highest lesion SNR, liver SNR, and CNR (p < 0.05). Interreader agreement was excellent (ICC = 0.839-0.953). ADC values correlated strongly across sequences (rₛ = 0.812-0.961, p < 0.001). Boost iShim-DWI achieved the highest diagnostic performance (AUC = 0.942; 95% CI 0.897-0.988). Discussion: Boost iShim-DWI improves liver DWI image quality while preserving ADC comparability and may enhance differentiation of benign and malignant focal liver lesions.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149008710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of a nonlinear double-breast single-axis gradient coil with controlled anterior-posterior gradient variation for diffusion-weighted imaging.","authors":"Feng Jia, Gerrit C Arends, Philipp Amrein, Edwin Versteeg, Dennis W J Klomp, Maxim Zaitsev, Chantal M W Tax, Sebastian Littin","doi":"10.1007/s10334-026-01420-0","DOIUrl":"https://doi.org/10.1007/s10334-026-01420-0","url":null,"abstract":"<p><strong>Introduction: </strong>High-performance whole-body gradient systems show promise for breast diffusion-weighted imaging, but their performance is constrained by physiological limits. Although local nonlinear gradient coils can provide stronger gradients while remaining within these limits, they often exhibit a substantial reduction in the gradient amplitude of the z-component of the magnetic field near the chest wall.</p><p><strong>Methods: </strong>We introduced an optimization framework incorporating a constraint on the anterior-posterior variation in the encoding gradient amplitude. A figure of merit combining coil efficiency and minimum wire width was defined to assess performance. A prototype was constructed to validate the design methodology.</p><p><strong>Results: </strong>The optimized coil achieved a 2.35-fold efficiency increase over standard linear coils. Compared to previous nonlinear designs, the new constraint reduced spatial variation by 35.7% and improved minimum efficiency near the chest wall by 2.6-fold. Experimental field maps matched simulations with errors under 8%.</p><p><strong>Discussion: </strong>The proposed method effectively mitigates the trade-off between gradient strength and spatial uniformity along anterior-posterior direction. By enhancing performance in the posterior breast region, the design addresses a critical limitation of previous local coils.</p><p><strong>Conclusion: </strong>This framework enables the development of high-performance, robust local gradient coils, facilitating the clinical implementation of advanced DWI protocols for breast cancer screening.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149008678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advances in hypoxia-modulated blood oxygen level-dependent MRI: a narrative review of physiological principles and applications for glioblastoma imaging.","authors":"Tristan Schmidlechner, Vittorio Stumpo, Elisabeth Jehli, Leonie Zerweck, Meltem Gönel, Jacopo Bellomo, Christiaan Hendrik Bas van Niftrik, Martina Sebök, Andrea Bink, Zsolt Kulcsar, Michael Weller, Luca Regli, Jorn Fierstra","doi":"10.1007/s10334-026-01409-9","DOIUrl":"https://doi.org/10.1007/s10334-026-01409-9","url":null,"abstract":"<p><p>Glioma imaging remains constrained by the limited ability of conventional MRI to capture biologically relevant tumor features beyond blood-brain barrier disruption. Hypoxia-modulated blood oxygen level-dependent (BOLD) MRI has emerged as a potential contrast-agent-free approach to probe oxygenation-related tumor physiology, using deoxyhemoglobin as an endogenous susceptibility contrast mechanism. By altering blood oxygenation during acquisition, the technique generates signal changes that may provide physiological information beyond structural imaging and resting perfusion measures. We performed a narrative review of 29 human and animal studies using hypoxic oxygen challenges during BOLD MRI. Substantial heterogeneity was identified in gas delivery, carbon dioxide control, MRI acquisition and analytical approaches. A recurring methodological issue was carbon dioxide control, since carbon dioxide is the dominant vasoactive stimulus and hypoxia-induced hyperventilation with secondary hypocapnia can confound BOLD signal interpretation. Preclinical brain tumor studies suggest sensitivity to spatial heterogeneity between viable and necrotic tumor regions. Early human glioblastoma studies support the feasibility and tolerability of hypoxia-modulated BOLD acquisitions and show spatially heterogeneous signal- and perfusion-related maps without exogenous contrast. Current evidence supports hypoxia-modulated BOLD MRI as a promising translational imaging approach, but clinical data remain limited and prospective validation in glioblastoma cohorts is required.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148956154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ESMRMB 2026 focus topic: future of MR in society.","authors":"Maria Eugenia Caligiuri, Karin Markenroth Bloch, Rita Gouveia Nunes, Claude Portanier Mifsud, Joan Carlos Vilanova, Lukas Winter, Patricia Clement","doi":"10.1007/s10334-026-01413-z","DOIUrl":"https://doi.org/10.1007/s10334-026-01413-z","url":null,"abstract":"","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148912648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction: Automated, open-source, vendor-independent quality assurance protocol based on the Pulseq framework.","authors":"Qingping Chen, Niklas Wehkamp, Cai Wan, Patrick Hucker, Martin Büchert, Sebastian Littin, Jon-Fredrik Nielsen, Maxim Zaitsev","doi":"10.1007/s10334-026-01417-9","DOIUrl":"https://doi.org/10.1007/s10334-026-01417-9","url":null,"abstract":"","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148912593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}