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

{"title":"Towards an anthropomorphic MRI phantom mimicking static and dynamic B₀ field variations in the human cervical spinal cord.","authors":"Laura Beghini, Brunnhilde M A-S Ponsi, Kamilla Refsholt, Annelen Dogger Schmidt, Virginie Callot, S Johanna Vannesjo","doi":"10.1007/s10334-026-01349-4","DOIUrl":"https://doi.org/10.1007/s10334-026-01349-4","url":null,"abstract":"<p><strong>Objective: </strong>Spinal cord MRI is heavily affected by static and dynamic B₀ field variations. The aim of this study was to develop an anthropomorphic cervical spine phantom that replicates these.</p><p><strong>Materials and methods: </strong>The phantom consisted of a 3D-printed head-to-thorax shell containing 3D-printed vertebrae (C1-T1) in a water-based liquid solution. An external respiration system mimicked breathing-induced field fluctuations by moving metal staples over the phantom. The accuracy of the reproduced fields was evaluated at 7 T by field maps and multi-echo GREs acquired in the phantom and in four subjects.</p><p><strong>Results: </strong>Fourier-based field simulations confirmed the vertebrae to be the main contributors to the local static field in the spinal canal, providing a rationale for the phantom design. The 3D-printed vertebrae accurately reproduced the spatial field pattern encountered in vivo, but with one-third of the intensity due to lower susceptibility differences. The respiration system produced spatially and temporally similar dynamic field fluctuations as in vivo.</p><p><strong>Discussion: </strong>The phantom was designed to be low-cost, modular and reproducible, while also being non-toxic and free from biological hazards. It may serve as a useful tool for development and testing of correction strategies to address the persistent challenge of B₀ field variations in spinal cord MRI.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147691019","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":"CMR T1 and T2 mapping and extracellular volume quantification in systolic phase produces superior image quality with less motion artifacts and equal mapping values compared to conventional diastolic mapping.","authors":"Johanna Federico, Suvi Syväranta, Miia Holmström, Jyri Lommi, Satu Suihko, Ritva Peltomaa, Riitta Koivuniemi, Marjatta Leirisalo-Repo, Juha Peltonen, Touko Kaasalainen, Satu Vaara","doi":"10.1007/s10334-026-01353-8","DOIUrl":"https://doi.org/10.1007/s10334-026-01353-8","url":null,"abstract":"<p><strong>Aim: </strong>This study investigated whether systolic phase imaging improves cardiac magnetic resonance (CMR) mapping by reducing artifacts compared with diastolic phase analyses. We evaluated T1 and T2 relaxation times and extracellular volume (ECV) in healthy individuals, early rheumatoid arthritis (ERA), and aortic stenosis (AS) patients.</p><p><strong>Materials and methods: </strong>A total of 114 participants (54 healthy adults, 30 ERA and 30 AS patients) underwent 1.5 T CMR with T1, T2, and ECV mapping in both diastolic and systolic phases. Imaging artifacts were categorized as minor or major, and inter-observer agreement was assessed for image quality and reproducibility.</p><p><strong>Results: </strong>Systolic phase mapping significantly reduced minor imaging artifacts across all cohorts (14% vs 5%, p < 0.001 for T1; 5% vs 2%, p < 0.001 for T2 in healthy cohort), particularly in participants with thinner myocardium. Inter-observer agreement assessed in the ERA cohort was excellent, with higher intraclass correlation coefficients (ICC) for systolic than diastolic mapping, particularly for T2 (0.975 vs 0.867) and ECV (0.951 vs 0.891). Systolic mapping yielded comparable T1 and T2 relaxation times across all cohorts.</p><p><strong>Conclusions: </strong>Systolic mapping provides comparable T1, T2, and ECV values to diastolic mapping, while reducing artifacts, supporting its clinical applicability across diverse patient profiles.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147690978","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":"Trans-cytolemmal water exchange in prostate manifest via DCE-MRI.","authors":"Xin Li, Ryan P Kopp, William D Rooney, Charles S Springer, Fergus V Coakley, Mark G Garzotto","doi":"10.1007/s10334-026-01345-8","DOIUrl":"https://doi.org/10.1007/s10334-026-01345-8","url":null,"abstract":"<p><strong>Objective: </strong>To investigate the potential of the unidirectional cellular water efflux rate constant (k_io) from DCE-MRI data in prostate MR imaging.</p><p><strong>Materials and methods: </strong>High-temporal-resolution prostate DCE-MRI data were modeled using both the fast-exchange-limit (FXL) Tofts' model as well as the water-exchange-sensitized shutter-speed model (SSM). In the SSM, k_io was included as an additional fitting parameter. Lesion and normal-appearing (NA) prostate tissue region-of-interest (ROI) data were analyzed and categorized into FXL or non-FXL conditions based on results from the two models. A global upper limit of k_io detectable by prostate DCE-MRI with the SSM was presented.</p><p><strong>Results: </strong>While many lesion voxels exhibited sensitivity to k_io with the SSM, a substantial portion remained in the FXL condition despite greater contrast agent extravasation than in NA tissue. The fraction of FXL voxels was higher in lesions than in NA tissue. Applying a global detectable k_io upper limit increased the difference between lesion and NA ROIs, improving lesion characterization.</p><p><strong>Discussion: </strong>SSM-derived FXL and non-FXL contrasts may serve as novel imaging biomarkers for prostate cancer surveillance. Advances in MRI technology and more potent contrast agents are expected to enhance the accuracy of k_io quantification, potentially enabling its integration into clinical mpMRI.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147690966","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":"Phase-constrained zero-shot self-supervised learning for BLADE liver MRI reconstruction.","authors":"Uten Yarach, Sorravit Akrasirakul, Hendrik Mattern, Oliver Speck","doi":"10.1007/s10334-026-01359-2","DOIUrl":"https://doi.org/10.1007/s10334-026-01359-2","url":null,"abstract":"<p><strong>Introduction: </strong>Liver MRI plays a critical role in the diagnosis and monitoring of liver disease; however, image quality is often degraded by respiratory motion and noise, particularly in high-resolution and diffusion-weighted imaging. Propeller-based sequences such as BLADE improve motion robustness, but advanced reconstruction strategies are required to fully exploit their potential under accelerated conditions.</p><p><strong>Methods: </strong>We propose a phase-constrained zero-shot self-supervised learning (PC ZS-SSL) framework for BLADE liver MRI reconstruction. The method embeds BLADE forward and adjoint operators within an unrolled deep network together with an explicit phase estimation module. Unlike supervised approaches, PC ZS-SSL requires no external training data and instead leverages partitioned k-space. The framework was first evaluated using structured phantom experiments assessing spatial resolution and low-contrast detectability, and subsequently applied to in vivo 3 T T2-weighted (T2W, 20 blades) and diffusion-weighted imaging (DWI, 18 and 15 blades, b = 0, 800 s/mm²). Performance was compared with locally low-rank (LLR) and vendor-provided reconstructions.</p><p><strong>Results: </strong>In phantom studies, PC ZS-SSL preserved fine structural details and demonstrated improved sharpness compared with fewer gradient updates and LLR. In vivo, PC ZS-SSL consistently reduced noise and ringing artifacts while maintaining anatomical fidelity. In T2W imaging, it achieved image quality comparable to LLR with fewer artifacts. In DWI, where noise is more pronounced, PC ZS-SSL provided clearer organ boundaries than both LLR and vendor reconstructions. Additional in vivo evaluation demonstrated that PC ZS-SSL remained robust under severe undersampling conditions (e.g., 4 blades) and challenging imaging scenarios, where LLR reconstructions exhibited residual artifacts.</p><p><strong>Conclusion: </strong>PC ZS-SSL enables high-quality, artifact-suppressed BLADE liver MRI without the need for external training data. Its strong performance in both phantom and in vivo experiments-particularly under high-noise diffusion conditions-highlights its potential for clinical translation.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147654109","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":"Effects of gadolinium-based contrast agents on the cardiac diffusion-weighted images of phantoms and patients.","authors":"Satonori Tsuneta, Satoru Aono, Jihun Kwon, Masami Yoneyama, Hiroki Uehara, Takuya Aoike, Sakae Takenaka, Hidenori Koyano, Noriyuki Fujima, Toshiyuki Nagai, Toshihisa Anzai, Kazuyuki Minowa, Kohsuke Kudo","doi":"10.1007/s10334-026-01356-5","DOIUrl":"https://doi.org/10.1007/s10334-026-01356-5","url":null,"abstract":"<p><strong>Objectives: </strong>To investigate the effects of gadolinium-based contrast agent (GBCA) on cardiac diffusion-weighted imaging (cDWI) and cDWI feasibility during the interval between GBCA administration and late gadolinium enhancement (LGE) imaging to streamline workflow.</p><p><strong>Materials and methods: </strong>Phantoms containing varying GBCA concentration (0-1.0 mM/L) were scanned with stimulated echo acquisition mode-based cDWI (STEAM-cDWI) with various heart rates (HRs) (30-200 beats/min) and second-order motion-compensated spin-echo-based cDWI (M2SE-cDWI) with various echo times (TEs) (75-500 ms). For patient study, 9 patients underwent STEAM-cDWI and 13 underwent M2SE-cDWI before and after GBCA administration. Contrast ratio (CR) and contrast-to-noise ratio (CNR) between the left ventricular myocardium and cavity, and ADC values were assessed.</p><p><strong>Results: </strong>In phantoms, higher GBCA concentration, lower HR, and prolonged TE reduced SI. In STEAM-cDWI, CR and CNR significantly reduced after GBCA administration (CR of b = 400, 2.29 [1.80-5.46] vs. 1.15 [0.78-1.29], p = 0.0004; CNR of b = 400, 7.58 [4.82-11.1] vs. 0.57 [- 1.34 to 1.35], p = 0.0006; respectively); ADC values remained unchanged. In M2SE-cDWI, ADC values significantly decreased after GBCA administration (1.62 [1.15-1.97] vs. 1.26 [1.12- 1.51], × 10^-3 mm²/s respectively, p = 0.004); only CR at b = 400 decreased significantly.</p><p><strong>Discussion: </strong>cDWI is not recommended during the interval between GBCA administration and LGE imaging.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147645689","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":"Mastering preclinical proton and deuterium-based fast MRSI in the brain: from setup to execution.","authors":"Gianna Nossa, Eloïse Mougel, Brayan Alves, Tan Toi Phan, Alessio Siviglia, Thi Ngoc Anh Dinh, Thanh Phong Lê, Bernard Lanz, Cristina Cudalbu","doi":"10.1007/s10334-026-01352-9","DOIUrl":"https://doi.org/10.1007/s10334-026-01352-9","url":null,"abstract":"<p><p>MR experiments are essential for studying brain metabolism, yet preclinical MRSI remains underdeveloped, with significant limitations in SNR, acquisition speed, and automated data processing. Although recent advances-such as accelerated sequences, denoising strategies, and ultra-high-field systems-have begun to reduce these barriers; preclinical MRSI still lags far behind the human research field in accessibility and routine use. Based on our expertise, we have created this guide that outlines a complete workflow for acquiring and analyzing high-quality fast-proton and deuterium-based MRSI data in rodent brains at ultra-high fields (9.4 T and 14.1 T), enabling novice users to perform reliable experiments using optimized MRSI sequences (FID-MRSI, SE-MRSI, and PRESS-MRSI) and standardized processing pipelines, while also highlighting strategies to further improve acquisition speed, coverage, and reproducibility. Overall, this paper provides a strong foundation for future methodological advances that will expand metabolic imaging capabilities and deepen insights into brain metabolism and disease.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147633299","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":"MRS4Brain: a software for preclinical proton and deuterium-based MR spectroscopic imaging data.","authors":"Brayan Alves, Tan Toi Phan, Guillaume Briand, Alessio Siviglia, Gianna Nossa, Jessie Mosso, Eloïse Mougel, Jamie Near, Thi Ngoc Anh Dinh, Omar Zenteno, Bernard Lanz, Thanh Phong Lê, Cristina Cudalbu","doi":"10.1007/s10334-026-01351-w","DOIUrl":"https://doi.org/10.1007/s10334-026-01351-w","url":null,"abstract":"<p><strong>Objectives: </strong>Magnetic resonance spectroscopic imaging (MRSI) is a non-invasive technique for probing metabolism. MRSI enables spatial mapping of metabolite distributions, offering insights into regional metabolic heterogeneity that single-voxel spectroscopy (SVS) cannot capture. However, MRSI produces large multidimensional datasets and requires complex processing pipelines, limiting reproducibility and accessibility. While human studies benefit from advanced processing tools, similar developments in preclinical research remain scarce, highlighting a demand for practical tools accessible to non-experts. Furthermore, recent advances in deuterium-based MRSI have opened metabolic pathway studies, introducing additional dimensions for kinetic information and specific positional labeling, thus substantially increasing dataset complexity and analysis demands.</p><p><strong>Methods: </strong>To address these needs, we introduce the MRS4Brain Toolbox, a freely available MATLAB-based platform for preclinical MRSI supporting proton, deuterium, and other nuclei, with extended functionalities for SVS and diffusion-weighted spectroscopy.</p><p><strong>Results: </strong>The toolbox integrates reconstruction, preprocessing, quantification, quality control, brain segmentation automatically overlaid on metabolite maps, modeling, and statistical analysis into unified workflows accessible via a graphical interface.</p><p><strong>Conclusion: </strong>By streamlining data processing and reducing technical barriers, MRS4Brain Toolbox promotes reproducibility, harmonization, and broader adoption of basic and advanced spectroscopic techniques in preclinical studies, ultimately facilitating translational metabolic research.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147633391","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":"Assessing the treatment of pancreatic ductal adenocarcinoma by deuterium metabolic imaging: a preclinical study.","authors":"Elton T Montrazi, Maya Kovalevsky, Keren Sasson, Lilach Agemy, Avigdor Scherz, Lucio Frydman","doi":"10.1007/s10334-026-01340-z","DOIUrl":"https://doi.org/10.1007/s10334-026-01340-z","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the utility of Deuterium Metabolic Imaging (DMI) as a tool for monitoring disease progression and assessing the therapeutic efficacy of cyclophosphamide in pancreatic ductal adenocarcinoma (PDAC).</p><p><strong>Methods: </strong>The study utilized C57BL mice implanted with a PDAC model, and separated into two experimental groups: One cohort served as an untreated control, while the second was treated with the chemotherapeutic agent cyclophosphamide (CP). Metabolic mapping for the two cohorts was performed over the course of weeks using 2H MRSI at 15.2T, tracking the metabolic pathway of deuterated glucose as it converts by the PDAC into lactate.</p><p><strong>Results: </strong>CP administration led to a significant reduction in tumor growth and improved survival rates compared to the control group. Tumor growth rates for the untreated, control group, showed a strong inverse correlation for glucose's uptake and a strong direct correlation with the glucose-to-lactate conversion rates as seen by DMI. CP treatment disrupted both these correlations: Post-treatment, tumor growth rates became statistically uncorrelated with either glucose consumption or lactate production which, when normalized for tumor size, remained relatively constant during the treatment period.</p><p><strong>Conclusion: </strong>The study demonstrates that CP treatment fundamentally alters the metabolic kinetics of glucose in PDAC tumors, inducing disruptions in metabolic correlations that may serve for distinguishing therapeutic success from failure.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147623239","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":"Hippocampal volume from T1 MRI as an atrophy biomarker: automated calculation and Scheltens' scale correlation.","authors":"Panagiotis Koussis, Panagiotis Toulas, Christos Karanikas, Demetrios Glotsos, Eleni Lamprou, Dimitrios Kechagias, Eleftherios Lavdas","doi":"10.1007/s10334-026-01329-8","DOIUrl":"https://doi.org/10.1007/s10334-026-01329-8","url":null,"abstract":"<p><strong>Objective: </strong>Scheltens' discrete scale is widely used for assessing brain atrophy but has limitations in subjectivity and tracking patient progression over short periods. Automated brain volumetry offers a more objective imaging approach for diagnosing neurodegenerative diseases. This retrospective study aims to correlate Scheltens' scale assessments with hippocampal and cerebrum volumes measured by volBrain, enhancing patient care.</p><p><strong>Materials and methods: </strong>This study involved 106 participants, including healthy volunteers and patients with mild cognitive impairment, all scanned using a standardized MRI protocol. Two radiologists assessed medial temporal lobe atrophy, while volBrain automated the volumetric measurements. Reliability between raters was evaluated using the intra-class correlation coefficient and Kappa analysis. Shapiro-Wilk test performed to evaluate the normality of data distribution, Spearman's, Kruskal-Wallis, and Dunn's ad hoc tests used to compare the Scheltens' scale with volumetric data. Receiver operating characteristic analysis performed for the radiologist evaluations and ordinal logistic regression used to model the probability of Schelten's scores with relative hippocampal volumes.</p><p><strong>Results: </strong>Raters had almost perfect agreement. Scheltens' scale correlations with hippocampus volumetric measurements were strongly significant, but correlations with cerebrum volumetric measurements were weak. Automated brain volumetric software presented 82% sensitivity and 100% specificity. Ordinal logistic regression presented overall model significance.</p><p><strong>Discussion: </strong>This study suggests that hippocampus relative volume is a sensitive biomarker for atrophy evaluation toward an advanced, medial lobe atrophy scale, providing clinicians with a precise and objective tool.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2026-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147609359","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":"Fast 3D-MRSI using sparse acquisition and 4D compressed sensing reconstruction.","authors":"Jian-Xiong Wang","doi":"10.1007/s10334-025-01301-y","DOIUrl":"10.1007/s10334-025-01301-y","url":null,"abstract":"<p><strong>Background: </strong>Magnetic Resonance Spectroscopic Imaging (MRSI), also known as Chemical Shift Imaging (CSI), is a pivotal tool in both clinical and preclinical metabolic research. Traditional MRSI offers high sensitivity to weak metabolites and covers a wide spectral bandwidth. However, the large number of RF excitations required for fully sampled 3D-MRSI acquisitions renders it impractical for hyperpolarized (HP) MRI applications, especially given the rapid signal decay and non-renewable magnetization of HP agents such as [1-¹³C]pyruvate.</p><p><strong>Purpose: </strong>This study aims to develop and validate an accelerated MRSI method that can preserve broad spectral bandwidth and weak metabolite detectability without aliasing, overcoming limitations of fast MRSI techniques such as echo-planar spectroscopic imaging (EPSI), which typically cause narrower spectral bandwidth and can suffer from spectral aliasing.</p><p><strong>Methods: </strong>We implemented a sparsely sampled 3D-MRSI pulse sequence on an MRI scanner, acquiring data with large reduction ratios. A 4D compressed sensing (CS) reconstruction algorithm was developed to recover high-resolution spectroscopic data from undersampled measurements. The algorithm jointly reconstructs the three spatial dimensions and the frequency dimension, leveraging sparsity priors and iterative conjugate gradient optimization. The in vivo experiments were performed on a GE 3 T clinical MRI scanner (GE MR750W) using hyperpolarized [1-¹³C]pyruvate in one rat, with two acquisitions (R = 8 and R = 16) performed sequentially.</p><p><strong>Results: </strong>Our method achieved high-quality reconstructions even at acceleration factors of R = 16 and R = 32, corresponding to 6.25 and 3.125% sampling, respectively. The normalized root-mean-square error (nRMSE) and structural similarity index (SSIM) remained low (nRMSE < 4 × 10^-3, SSIM > 0.95) even at high undersampling rates. In vivo experiments using hyperpolarized [1-¹³C]pyruvate in rat kidneys demonstrated the ability to resolve lactate, alanine, pyruvate, and bicarbonate distributions with high spatial and spectral fidelity.</p><p><strong>Conclusion: </strong>The integration of sparse MRSI acquisition and 4D-CS reconstruction enables rapid, high-fidelity MRSI with HP ¹³C-MRSI. This approach reduces acquisition time by up to 32-fold, facilitating dynamic metabolic studies and improving feasibility for routine preclinical and future clinical use.</p>","PeriodicalId":18067,"journal":{"name":"Magnetic Resonance Materials in Physics, Biology and Medicine","volume":" ","pages":"253-264"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13124777/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145426515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}