Journal of Magnetic Resonance Imaging最新文献

{"title":"MR-Guidance of Gene Therapy for Brain Diseases: Moving From Palliative Treatment to Cures.","authors":"Dalton H Bermudez, Thomas Lilieholm, Walter F Block","doi":"10.1002/jmri.29804","DOIUrl":"https://doi.org/10.1002/jmri.29804","url":null,"abstract":"<p><p>Regulatory bodies in the U.S. and Europe recently approved a gene therapy for aromatic L-amino acid decarboxylase (AADC) deficiency, a rare neurologic disorder where a genetic mutation prevents dopamine production in the brain. Affected children fail to develop normal motor and cognitive functions. MRI-guided intraparenchymal delivery of AADC gene therapy to localized gray matter regions-specifically the substantia nigra and ventral tegmental area-has enabled the brain to produce dopamine, resulting in dramatic improvements in physical and cognitive outcomes. The need to target only a small brain region simplifies the surgical approach. However, gene therapy for broader neurodegenerative conditions has progressed more slowly than expected, despite significant global investment. Clinical efficacy depends heavily on the accurate delivery of gene therapeutics via direct brain infusion, cerebrospinal fluid (CSF) administration, or both. Inadequate image guidance during clinical trials makes it difficult to distinguish between true drug inefficacy and delivery failure. We highlight how increasing use of MRI for pre-surgical simulation and real-time therapy monitoring is accelerating gene therapy development for neurological diseases. This manuscript explores MRI's role in guiding intraparenchymal gene delivery, particularly using Convection Enhanced Delivery (CED). MRI contributes across the treatment timeline-from pre-surgical planning and infusion guidance to validating therapeutic coverage. We describe how MRI supports controlled therapeutic distribution for localized treatments and its potential to enable broader distributions needed for correcting widespread genetic anomalies. We also detail how structural and anatomical MRI sequences (T1, T2, Time of Flight, and Diffusion Tensor Imaging (DTI)) can help model likely infusion distributions. Finally, we provide an outlook on how advanced DTI-based algorithms and poroelastic theory could further improve modeling of infusion dynamics. Current MRI-based technologies can be integrated and enhanced to improve CED effectiveness, especially in very young pediatric patients. EVIDENCE LEVEL: 1. TECHNICAL EFFICACY: Stage 4.</p>","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144014508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Application of Quasi-Steady-State Chemical Exchange Saturation Transfer Imaging in the Visualization of Glioma Infiltration and the Optimal Extent of Resection Establishment.","authors":"Yinwei Ying, Dongdong Wang, Yajing Zhao, Kai Quan, Xuanxuan Li, Yuxi Xie, Nan Mei, Jie Chen, Zhuoying Ruan, Rong Xu, Guoqiang Ren, Ruibin Liu, Yin Wu, Yiping Lu, Bo Yin","doi":"10.1002/jmri.29786","DOIUrl":"https://doi.org/10.1002/jmri.29786","url":null,"abstract":"<p><strong>Background: </strong>The quasi-steady-state (QUASS) algorithm improves chemical exchange saturation transfer (CEST) reliability, but its efficacy in detecting glioma infiltration is unclear.</p><p><strong>Purpose: </strong>To assess apparent and QUASS CEST in visualizing glioma infiltration and predicting optimal extent-of-resection (EOR).</p><p><strong>Study type: </strong>Prospective.</p><p><strong>Population: </strong>72 adult-type diffuse glioma patients (37 males, 49.57 ± 14.76 years) and 24 healthy volunteers (12 males, 48.71 ± 14.23 years).</p><p><strong>Fieldstrength/sequence: </strong>3 T, fast spin-echo CEST.</p><p><strong>Assessment: </strong>Apparent and QUASS CEST effects (amide proton transfer [APT], combined magnetization transfer and nuclear overhauser enhancement and the 2-ppm chemical exchange saturation transfer peak) were calculated in solid tumor, edema, contralateral normal apparent white matter (CNAWM) in glioma patients, and white matter in healthy individuals (WMH). Comparisons were made between these four regions, high-/low-grade gliomas (HGGs/LGGs), and isocitrate dehydrogenase (IDH)-mutant/wild-type gliomas. Twenty-seven biopsy samples from glioblastomas and peritumoral regions were selected and traced back to the original images. Then, correlations between CEST effects, cellularity, and Ki-67 labeling index (LI) were assessed. An optimal cutoff value for the normalized ratios of QUASS APT (QUASS_rAPT) was generated.</p><p><strong>Statistical tests: </strong>Linear mixed models, t-test, receiver-operating characteristic analysis, and Pearson's correlation tests were used. The statistical significance was set at p ≤ 0.05.</p><p><strong>Results: </strong>QUASS_APT value decreased significantly from tumor solid area, edema, and CNAWM to WMH (3.887 ± 1.489, 2.556 ± 0.985, and 1.584 ± 0.462, respectively). QUASS_rAPT of solid tumor area differentiated LGGs from HGGs (1.878 ± 0.515 vs. 2.857 ± 1.026) and IDH-mutant gliomas from IDH wild-type gliomas (2.195 ± 0.769 vs. 2.875 ± 1.092). QUASS_rAPT strongly correlated with cell density and Ki-67 LI (r = 0.801 and 0.776). The optimal cutoff value of QUASS_rAPT was 1.300.</p><p><strong>Data conclusion: </strong>Compared to other CEST effects and apparent methods, QUASS_rAPT enhances glioma stratification and better reflects cell density and proliferative potential. A QUASS_rAPT > 1.30 optimized EOR prediction in glioblastomas.</p><p><strong>Evidence level: </strong>2 TECHNICAL EFFICACY: Stage 2.</p>","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144040177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-Center, Multi-Vendor Validation of Simultaneous MRI-Based Proton Density Fat Fraction and R2* Mapping Using a Combined Proton Density Fat Fraction-R2* Phantom.","authors":"Jitka Starekova, David Rutkowski, Won C Bae, Hung Do, Ananth J Madhuranthakam, Vadim Malis, Sheng Qing Lin, Suraj Serai, Takeshi Yokoo, Scott B Reeder, Jean H Brittain, Diego Hernando","doi":"10.1002/jmri.29775","DOIUrl":"https://doi.org/10.1002/jmri.29775","url":null,"abstract":"<p><strong>Background: </strong>Fat and iron deposition confound measurements of R2* and proton density fat fraction (PDFF), respectively, yet their combined impact on reproducibility is poorly understood.</p><p><strong>Purpose: </strong>To evaluate the multi-center, multi-vendor reproducibility of PDFF and R2* quantification using a PDFF-R2* phantom.</p><p><strong>Study type: </strong>Prospective multi-center, phantom study.</p><p><strong>Phantom: </strong>Commercial PDFF-R2* phantom with simultaneously controlled combination of PDFF (0%-30%) and R2* (50-600 s^-1) values.</p><p><strong>Field strength/sequence: </strong>1.5-T and 3-T, three-dimensional (3D) multi-echo, spoiled-gradient-echo sequences, in four different centers, each with a different vendor.</p><p><strong>Assessment: </strong>Two acquisition protocols were used, optimized for moderate R2* (Protocol 1) and high R2* (Protocol 2), respectively. The phantom was imaged multiple times at one of the centers to assess its stability.</p><p><strong>Statistical tests: </strong>Intraclass correlation coefficient (ICC), linear regression analysis, reproducibility coefficient (RDC) and repeatability coefficient (RC).</p><p><strong>Results: </strong>Excellent agreement was observed for PDFF measurements between centers, vendors, field strengths, and protocols (ICC = 0.97). Stratified by protocol, excellent agreement was observed, with ICC = 0.96 (RDC = 6.2%) for Protocol 1 and ICC = 0.99 (RDC = 3.8%) for Protocol 2. Increased variability in PDFF measurements was observed with increasing PDFF and especially with higher R2*. Excellent agreement was observed for R2* between centers, vendors, field strengths, and protocols (ICC = 0.99). Stratified by protocol, strong agreement was observed, with ICC = 0.988 (RDC = 66.7 s^-1) for Protocol 1 and ICC = 0.99 (RDC = 57.7 s^-1) for Protocol 2. Higher variability in R2* measurements was observed in vials with higher PDFF or R2*. Stability tests demonstrated an ICC = 1.0 for PDFF and R2*, and RC of 0.4% for PDFF and 12 s^-1 for R2*.</p><p><strong>Data conclusion: </strong>Excellent PDFF and R2* reproducibility was observed across centers, vendors, field strengths, and acquisition protocols. Reproducibility decreased slightly with increasing PDFF and R2*, especially for PDFF measurements in vials with high R2*.</p><p><strong>Evidence level: </strong>N/A.</p><p><strong>Technical efficacy: </strong>Stage 1.</p>","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144011189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility of Qualitative Evaluation and Quantitative T2 Mapping of Peripheral Nerves and Muscles Using GRAPPATINI.","authors":"A Z Lu, Y Lin, T Hilbert, Z Igbinoba, D Shakoor, X Cai, D B Sneag, E T Tan","doi":"10.1002/jmri.29803","DOIUrl":"https://doi.org/10.1002/jmri.29803","url":null,"abstract":"<p><strong>Background: </strong>Quantitative T2 mapping holds promise for evaluating peripheral nerve and muscle disorders, but current methods lack speed and diagnostic feasibility. As a proof of concept, T2 mapping may be applied to assess the abnormality of the common peroneal nerve (CPN), leading to denervation of the tibialis anterior muscle and subsequent foot drop.</p><p><strong>Purpose: </strong>To evaluate the GRAPPATINI sequence (a combination of generalized autocalibrating partially parallel acquisition [GRAPPA] and model-based accelerated relaxometry by iterative non-linear inversion [MARTINI]) for qualitative assessment and quantitative T2 mapping in patients with foot drop. We hypothesized that GRAPPATINI would yield comparable qualitative image quality to conventional T2-weighted (T2w) turbo spin echo (TSE) while detecting T2 differences between abnormal and normal nerves and muscles.</p><p><strong>Study type: </strong>Prospective, cross-sectional study.</p><p><strong>Population: </strong>27 subjects (13 females; mean age: 54.4 years; range: 17-85 years) with clinical suspicion or diagnosis of foot drop.</p><p><strong>Field strength/sequence: </strong>3-Tesla, with GRAPPATINI T2 mapping (spin echo) and T2w-TSE Dixon for unilateral MRI of the knee region.</p><p><strong>Assessment: </strong>Three radiologists, blinded to the sequence type and clinical data, evaluated nerve and muscle visualization, diagnostic confidence, and abnormal signal detection. Quantitative T2 values were measured in six manually segmented muscles and in the CPN and tibial nerve.</p><p><strong>Statistical tests: </strong>Wilcoxon rank sum tests compared T2 values between abnormal and normal muscles/nerves (p < 0.05 indicates statistical significance). Intra-class correlation coefficients (ICCs) assessed interobserver agreement.</p><p><strong>Results: </strong>Qualitative scores for nerve visualization, muscle visualization, and diagnostic confidence were similar between GRAPPATINI and T2w-Dixon (p = 1.0). T2 values were significantly higher in all abnormal versus normal muscles (66.5 vs. 45.7 ms) and in all abnormal versus normal nerves (66.8 vs. 60.5 ms).</p><p><strong>Data conclusion: </strong>GRAPPATINI provided comparable qualitative image quality to T2w imaging while enabling quantitative T2 mapping to detect abnormalities in muscles and nerves in patients with foot drop.</p><p><strong>Evidence level: </strong>2.</p><p><strong>Technical efficacy: </strong>Stage 2.</p>","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144025146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial for \"Multi-Center, Multi-Vendor Validation of Simultaneous MRI-Based Proton Density Fat Fraction and R2* Mapping Using a Combined Proton Density Fat Fraction-R2* Phantom\".","authors":"Kathryn E Keenan","doi":"10.1002/jmri.29782","DOIUrl":"https://doi.org/10.1002/jmri.29782","url":null,"abstract":"","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144040173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial for \"MRI Assessment of Geometric Microstructural Changes of White Matter in Infants With Periventricular White Matter Injury and Spastic Cerebral Palsy\".","authors":"Ravikanth Balaji, Bejoy Thomas, Neena Radhakrishnan","doi":"10.1002/jmri.29792","DOIUrl":"https://doi.org/10.1002/jmri.29792","url":null,"abstract":"","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144007580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fetal MRI: Radiofrequency Safety Assessment at 3 Tesla.","authors":"Filiz Yetisir, Esra Abaci Turk, Henry A Feldman, Borjan Gagoski, Ryne A Didier, Carol Barnewolt, Judy A Estroff, Lawrence L Wald, Elfar Adalsteinsson, P Ellen Grant","doi":"10.1002/jmri.29797","DOIUrl":"https://doi.org/10.1002/jmri.29797","url":null,"abstract":"<p><strong>Background: </strong>3-T MRI can improve image quality of fetal imaging compared to 1.5-T MRI. However, concerns exist regarding increased local tissue heating at 3-T.</p><p><strong>Purpose: </strong>To assess fetal MRI radiofrequency (RF) safety at 3-T by comparing simulated tissue heating to 1.5-T (using constant RF exposure) and by simulating tissue heating at 3-T using RF exposures from clinical fetal examinations.</p><p><strong>Study type: </strong>Retrospective.</p><p><strong>Population: </strong>Seven voxelized anatomical pregnant body models (gestational age [GA] 30 ± 3 weeks [mean ± standard deviation], maternal body mass index [BMI] 27.8 ± 8.5 kg/m²) were used. Maternal whole-body average specific absorption rate (wbSAR) logs were collected from 85 clinical examinations at 3-T (GA 25 ± 6 weeks, BMI 30.3 ± 6.8 kg/m²).</p><p><strong>Field strength/sequence: </strong>3-T, 1.5-T, HASTE, VIBE, TRUFISP, EPI, DTI.</p><p><strong>Assessment: </strong>Simulated maternal and fetal peak and average SAR, temperature, and peak thermal dose were compared at 3-T and 1.5-T for 60 min 2 W/kg wbSAR using 7 body models and a 16-rung band-pass RF coil. Temperature and thermal dose were simulated in one body model using clinical wbSAR exposures at 3-T.</p><p><strong>Statistical tests: </strong>Factorial analysis of variance was performed using 28 maternal and fetal temperature measurements from 7 body models to detect a difference between 3-T and 1.5-T. p < 0.05 was considered statistically significant.</p><p><strong>Results: </strong>For constant RF exposure, we found no difference between 3-T and 1.5-T in peak maternal (1.5-T:40.38 ± 0.21°C; 3-T:40.40 ± 0.20°C; p = 0.85), peak fetal (1.5-T:39.21 ± 0.17°C; 3-T:39.09 ± 0.16°C; p = 0.19), and average maternal (1.5-T:37.32 ± 0.05°C; 3-T:37.33 ± 0.04°C; p = 0.68) temperature. We observed significantly higher average fetal temperatures at 1.5-T (1.5-T:37.75 ± 0.06°C; 3-T:37.70 ± 0.05°C). For 3-T clinical RF exposures, simulated peak temperatures exceeded the recommended limits. However, the thermal dose was below the recommended limit.</p><p><strong>Data conclusion: </strong>For the same RF coil geometry, local heating was similar at 3-T and 1.5-T for constant RF exposure. Although realistic 3-T RF exposures could cause peak temperatures above the recommended limits, thermal dose was below the recommended limit.</p><p><strong>Evidence level: </strong>1.</p><p><strong>Technical efficacy: </strong>Stage 1.</p>","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144020768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Brain Tumor Characterization Using Multiple MR Parameters From Multi-Contrast EPI With Keyhole (GE-SE EPIK) Including Oxygen Extraction Fraction: A Comparison to O-(2-[18F]Fluoroethyl)-L-Tyrosine (FET) Positron Emission Tomography.","authors":"Fabian Küppers, Mohamed Kassem, Seong Dae Yun, Gabriele Stoffels, Christian Filß, Norbert Galldiks, Felix M Mottaghy, M Eline Kooi, Karl-Josef Langen, Philipp Lohmann, N Jon Shah","doi":"10.1002/jmri.29795","DOIUrl":"https://doi.org/10.1002/jmri.29795","url":null,"abstract":"<p><strong>Background: </strong>Tumor characterization and treatment efficacy are associated with tissue hypoxia. MR-derived oxygen extraction fraction (OEF) may offer valuable tumor insights but depends on multiple measurement parameters, often requiring multiple sequence acquisitions. Specific multi-parametric sequences offer direct access to MR parameter sets within short acquisition times.</p><p><strong>Purpose: </strong>To evaluate the potential of gradient-echo spin-echo echo-planar imaging with keyhole (GE-SE EPIK)-derived parameters (OEF/T₂/T₂*/venous cerebral blood volume (vCBV)) to characterize increased metabolic activity tissue identified in [¹⁸F]fluoroethyl-L-tyrosine (FET) PET, serving as a surrogate for neoplastic tissue.</p><p><strong>Study type: </strong>Retrospective.</p><p><strong>Population: </strong>Fifty-seven brain tumor patients (female/male:31/26; age 27-73 years) with 66 histologically confirmed lesions (suspected glioblastoma (16), glioblastoma (28), astrocytoma (11), metastasis (6), oligodendroglioma (5)).</p><p><strong>Field strength/sequence: </strong>10-echo GE-SE EPIK sequence at 3 T.</p><p><strong>Assessment: </strong>GE-SE EPIK data were acquired in a hybrid MR PET scanner during FET PET acquisitions. Two tumor segmentations based on FET-PET uptake and FLAIR hyperintensities were manually created. Mean GE-SE EPIK-derived parameters were calculated within tumor regions and compared to contralateral reference values. Relative tumor-to-reference parameters were compared across tumor types.</p><p><strong>Statistical tests: </strong>One/two-sampled, two-tailed t-tests of mean relative MR-derived parameters. p-value < 0.05 was considered significant.</p><p><strong>Results: </strong>Significantly increased T₂/T₂* and decreased vCBV/OEF were found in FET-PET and FLAIR-derived VOIs. Latter showed decreased R2'. Significant correlation between FET uptake and T₂/T₂* was found in FET-VOIs (Pearson correlation: 0.26/0.31, respectively). Oligodendrogliomas showed significant differences to glioblastomas (rR₂', rOEF) and astrocytomas (rR₂'). Metastasis showed different rT₂ values than suspected gliomas. Astrocytoma differed from gliomas in FET-TBR. Susceptibility artifacts in T₂* maps from air-tissue interfaces limited qualitative data interpretation.</p><p><strong>Data conclusion: </strong>GE-SE EPIK provides multiple MR parameters that are sensitive to expected changes in tumor regions obtained from FET and FLAIR thresholds. Susceptibility artifacts in T₂*/OEF maps made the differentiation between tumor relapse and treatment-related changes challenging. However, certain MR-derived parameters showed the ability to distinguish tumor types.</p><p><strong>Evidence level: </strong>3.</p><p><strong>Technical efficacy: </strong>Stage 2.</p>","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143970126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association of In Vivo Kidney Stiffness Measured by Multifrequency MR Elastography and Long-Term Renal Function in Transplant Recipients and Living Donors.","authors":"Stephan Rodrigo Marticorena Garcia, Jonas Oppenheimer, Tom Meyer, Frank Friedersdorff, Ingolf Sack","doi":"10.1002/jmri.29799","DOIUrl":"https://doi.org/10.1002/jmri.29799","url":null,"abstract":"<p><strong>Background: </strong>Kidney transplant (KTx) function assessment is important in treatment planning, while conventional MRI markers lack sensitivity for KTx function. Mechanical kidney properties may serve as MRI markers for renal allograft function.</p><p><strong>Hypothesis: </strong>To determine if multifrequency MR elastography (MRE) is associated with KTx function.</p><p><strong>Study type: </strong>Prospective, longitudinal.</p><p><strong>Subjects: </strong>Twelve kidney donors (51 ± 9 years, 8 females) and 12 allograft recipients (48 ± 17 years, 2 females).</p><p><strong>Fieldstrength/sequence: </strong>1.5 T, MRE, and diffusion-weighted MRI based on spin-echo echo-planar imaging and T2-weighted MRI volumetry.</p><p><strong>Assessment: </strong>Kidney donors were imaged pre- and post-KTx, while allograft recipients were imaged post-KTx. Renal function was assessed using creatinine levels (at 1 week, 1 month, and 3 years post-KTx in recipients) and glomerular filtration rate (GFR; donors pre-KTx) based on Tc-99m-MAG3 scintigraphy. Kidney volumes were measured by MRI segmentations, and ADC, shear-wave speed (SWS), and loss-angle maps were reconstructed. The correlations between MR parameters, GFR, and creatinine level (minimum value over study period) were investigated.</p><p><strong>Statistical tests: </strong>Wilcoxon tests and Pearson correlation coefficients (R). A p < 0.05 was considered statistically significant.</p><p><strong>Results: </strong>No significant lateral differences in renal volume (153 ± 34 cm³, p = 0.34) or SWS (2.5 ± 0.4 m/s, p = 0.20) were found pre-KTx. Volume and SWS increased significantly post-KTx in reference kidneys (volume: +13%, SWS: +11%) and in transplants in recipients (volume: +20%, SWS: +32%). SWS, but not volume (p = 0.75), correlated positively with GFR in donors pre-KTx (R = 0.67) while both SWS (R = ‑0.62) and volume (R = -0.77) negatively correlated with creatinine levels post-KTx. ADC was sensitive to KTx-associated changes in renal function in donors (3% ± 5%) but not recipients (p = 0.88).</p><p><strong>Data conclusion: </strong>MRE provides valuable information on renal function and could serve as a baseline for longitudinal monitoring of kidney transplants. Parenchymal stiffening post-KTx had significantly larger effect sizes in denervated allografts than in reference donor kidneys with intact autoregulation of renal blood flow.</p><p><strong>Evidence level: </strong>2.</p><p><strong>Technical efficacy: </strong>Stage 2.</p>","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144021241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial for \"Fetal MRI: Radiofrequency Safety Assessment at 3 Tesla\".","authors":"Jeffrey W Hand","doi":"10.1002/jmri.29800","DOIUrl":"https://doi.org/10.1002/jmri.29800","url":null,"abstract":"","PeriodicalId":16140,"journal":{"name":"Journal of Magnetic Resonance Imaging","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144007576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}