Magnetic Resonance in Medicine最新文献

{"title":"<ArticleTitle xmlns:ns0=\"http://www.w3.org/1998/Math/MathML\">Vessel segmentation for <ns0:math> <ns0:semantics><ns0:mrow><ns0:mi>χ</ns0:mi></ns0:mrow> <ns0:annotation>$$ chi $$</ns0:annotation></ns0:semantics> </ns0:math> -separation in quantitative susceptibility mapping.","authors":"Taechang Kim, Sooyeon Ji, Kyeongseon Min, Minjun Kim, Jonghyo Youn, Chungseok Oh, Jiye Kim, Jongho Lee","doi":"10.1002/mrm.70054","DOIUrl":"https://doi.org/10.1002/mrm.70054","url":null,"abstract":"<p><strong>Purpose: </strong><math> <semantics><mrow><mi>χ</mi></mrow> <annotation>$$ chi $$</annotation></semantics> </math> -separation is an advanced quantitative susceptibility mapping (QSM) method that is designed to generate paramagnetic ( <math> <semantics> <mrow><msub><mi>χ</mi> <mtext>para</mtext></msub> </mrow> <annotation>$$ {chi}_{para} $$</annotation></semantics> </math> ) and diamagnetic ( <math> <semantics><mrow><mo>|</mo> <msub><mi>χ</mi> <mi>dia</mi></msub> <mo>|</mo></mrow> <annotation>$$ mid {chi}_{dia}mid $$</annotation></semantics> </math> ) susceptibility maps, reflecting the distribution of iron and myelin in the brain. However, vessels have shown artifacts, interfering with the accurate quantification of iron and myelin in applications. To address this challenge, a new vessel segmentation method for <math> <semantics><mrow><mi>χ</mi></mrow> <annotation>$$ chi $$</annotation></semantics> </math> -separation is developed.</p><p><strong>Methods: </strong>The method comprises three steps: (1) seed generation from <math> <semantics> <mrow><msubsup><mi>R</mi> <mn>2</mn> <mo>*</mo></msubsup> </mrow> <annotation>$$ {R}_2^{ast } $$</annotation></semantics> </math> and the product of <math> <semantics> <mrow><msub><mi>χ</mi> <mtext>para</mtext></msub> </mrow> <annotation>$$ {chi}_{para} $$</annotation></semantics> </math> and <math> <semantics><mrow><mo>|</mo> <msub><mi>χ</mi> <mi>dia</mi></msub> <mo>|</mo></mrow> <annotation>$$ mid {chi}_{dia}mid $$</annotation></semantics> </math> maps; (2) region growing, guided by vessel geometry, creating a vessel mask; (3) refinement of the vessel mask by excluding non-vessel structures. The performance of the method was compared to other vessel segmentation methods both qualitatively and quantitatively. To demonstrate the utility of the method, it was tested in two applications: quantitative evaluation of a neural network-based <math> <semantics><mrow><mi>χ</mi></mrow> <annotation>$$ chi $$</annotation></semantics> </math> -separation reconstruction method ( <math> <semantics><mrow><mi>χ</mi></mrow> <annotation>$$ chi $$</annotation></semantics> </math> -sepnet- <math> <semantics> <mrow><msubsup><mi>R</mi> <mn>2</mn> <mo>*</mo></msubsup> </mrow> <annotation>$$ {R}_2^{ast } $$</annotation></semantics> </math> ) and population-averaged region of interest (ROI) analysis.</p><p><strong>Results: </strong>The proposed method demonstrates superior performance to other vessel segmentation methods, effectively excluding the non-vessel structures, achieving the highest Dice score coefficient against manually segmented vessel masks (3 T: 76.7% for <math> <semantics> <mrow><msub><mi>χ</mi> <mtext>para</mtext></msub> </mrow> <annotation>$$ {chi}_{para} $$</annotation></semantics> </math> and 68.7% for <math> <semantics><mrow><mo>|</mo> <msub><mi>χ</mi> <mi>dia</mi></msub> <mo>|</mo></mrow> <annotation>$$ mid {chi}_{dia}mid $$</annotation></semantics> </math> , 7 T: 76.9% for <math> <semantics> <mrow><msub","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Alternating-contrast single-shot spiral MR-ARFI with model-based displacement map reconstruction.","authors":"Saikat Sengupta, M Anthony Phipps, Li Min Chen, Charles F Caskey, William A Grissom","doi":"10.1002/mrm.70066","DOIUrl":"https://doi.org/10.1002/mrm.70066","url":null,"abstract":"<p><strong>Purpose: </strong>To improve single-shot spiral MR-Acoustic Radiation Force Imaging (MR-ARFI)'s robustness to dynamic phase errors and evaluate it in non-human primates (NHPs) with a low-f-number transducer.</p><p><strong>Methods: </strong>A single-shot spiral MR-ARFI pulse sequence with 2 mm in-plane resolution and alternating displacement phase contrast was implemented to visualize the focus generated by a 128-element ultrasound transducer in the NHP brain. A model-based displacement map calculation was implemented to remove dynamic phase errors. MR-ARFI scans were acquired at pressure levels above and below FDA mechanical index (MI) limits, and reconstructed displacement maps were compared to maps generated by a 3D EPI MR-ARFI scan and a spiral MR-ARFI scan with blocked ultrasound triggering.</p><p><strong>Results: </strong>The proposed sequence and processing detected focal tissue displacements of 160 nm at a transcranial mechanical index of 0.96, which the 3D EPI could not detect, and with 9.7 <math> <semantics><mrow><mo>×</mo></mrow> <annotation>$$ times $$</annotation></semantics> </math> -improved precision. The model-based reconstruction suppressed background phase errors and maximized precision. Alternating contrast yielded displacement maps with 4.9 <math> <semantics><mrow><mo>×</mo></mrow> <annotation>$$ times $$</annotation></semantics> </math> -improved precision compared to blocked contrast.</p><p><strong>Conclusion: </strong>Single-shot spiral MR-ARFI can provide robust focus visualization in MR-guided ultrasound in the brain at MI levels well below the FDA limit.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of simultaneous exposure to RF and gradient electromagnetic fields on implant MR safety labeling.","authors":"Umberto Zanovello, Alessandro Arduino, Carina Fuss, Tolga Goren, Luca Zilberti, Oriano Bottauscio","doi":"10.1002/mrm.70059","DOIUrl":"https://doi.org/10.1002/mrm.70059","url":null,"abstract":"<p><strong>Purpose: </strong>To investigate whether heating contributions produced by radiofrequency (RF) and gradient fields superpose sufficiently at the worst-case locations to justify their simultaneous consideration in magnetic resonance imaging (MRI) implant safety labeling.</p><p><strong>Theory and methods: </strong>Six implant models were positioned in an ASTM phantom and realistically implanted in two anatomical human models, and exposed to gradient and RF fields at 64 MHz and 128 MHz. The simulations with the anatomical body models considered different axial exposure landmarks inside the RF and gradient body coils. The exposures were scaled to represent two sets of scenarios: either limited by the implant's MR conditional labeling to a fixed peak temperature rise, or representing an EPI or TrueFISP examination with clinically relevant parameters, where the implant label is not limiting.</p><p><strong>Results: </strong>The temperature enhancement due to the combined RF and gradient sources, evaluated with respect to the maximum values obtained separately, depends on the implant, pulse sequence, and exposure landmark. A maximum relative enhancement of about 65% was found in the ASTM phantom, and maximum absolute enhancements above 0.3 K were found in anatomical models with realistic pulse sequences.</p><p><strong>Conclusion: </strong>There are clinically relevant MR examination scenarios where the maximum heating contributions produced by RF and gradient fields combine, enhancing the local peak temperature increase beyond that obtained from either assessment alone. The results prove to be useful for defining safety margins on the maximum allowable temperature increase, avoiding the requirement of a combined gradient coil and RF test.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison between multiparametric arterial spin labeling and [¹⁵O]H₂O positron emission tomography in patients with moyamoya disease.","authors":"Shota Ishida, Hirohiko Kimura, Makoto Isozaki, Kenji Takata, Yuki Matta, Tetsuya Tsujikawa, Hidehiko Okazawa","doi":"10.1002/mrm.70045","DOIUrl":"https://doi.org/10.1002/mrm.70045","url":null,"abstract":"<p><strong>Purpose: </strong>Multiparametric arterial spin labeling (MP-ASL) using delays alternating with nutation for tailored excitation (DANTE) pulse (MP-ASL_DANTE) can noninvasively quantify arterial cerebral blood volume (CBV_a) and the residence time of labeled spins in the microvascular compartment (ΔTT). We hypothesized that MP-ASL_DANTE could identify the early stages of hemodynamic impairment in patients with moyamoya disease (MMD) by detecting autoregulatory vasodilation, specifically the elevation of CBV_a. However, the clinical relevance of MP-ASL_DANTE has not yet been fully evaluated. Therefore, we compared MP-ASL_DANTE with [¹⁵O]H₂O positron emission tomography (PET) to assess its clinical relevance in patients with MMD.</p><p><strong>Methods: </strong>MP-ASL_DANTE was performed on 11 patients, and the parameters were estimated using simulation-based deep neural networks. Furthermore, cerebrovascular reactivity (CVR) was calculated from the cerebral blood flow (CBF) before and after acetazolamide challenge using [¹⁵O]H₂O PET. Spearman's correlation analyses and group comparisons were performed.</p><p><strong>Results: </strong>Although CBV_a (ρ = 0.0288; p = 0.6876) did not significantly correlate with PET-CVR, ΔTT showed a significant correlation with PET-CVR (ρ = -0.2599; p = 0.0002). Moreover, CBV_a could not differentiate between the normal and reduced CVR groups, regardless of the CBF conditions. However, within the normal CBF group, the reduced CVR group exhibited a significantly longer ΔTT than the normal CVR group (p = 0.0069), suggesting its capability to differentiate CVR conditions even under normal CBF conditions.</p><p><strong>Conclusion: </strong>The comprehensive use of MP-ASL_DANTE parameters enables a detailed noninvasive evaluation of cerebral hemodynamics in patients with MMD and potentially allows for the detection of early stages of hemodynamic impairment in these patients.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the effectiveness of distortion self-correction for CEST-EPI.","authors":"Yang Liu, Se Weon Park, Lok Hin Law, Kexin Wang, Licheng Ju, Jiadi Xu, Kannie W Y Chan, Jianpan Huang","doi":"10.1002/mrm.70048","DOIUrl":"https://doi.org/10.1002/mrm.70048","url":null,"abstract":"<p><strong>Purpose: </strong>EPI is a fast acquisition sequence, but suffers from geometric distortion because of B₀ field inhomogeneity. This study aims to evaluate the effectiveness of using ΔB₀ map generated from single-shot CEST-EPI to achieve distortion self-correction (DISC).</p><p><strong>Methods: </strong>CEST MRI usually requires B₀ correction during postprocessing, and the ΔB₀ map can be calculated directly from Z-spectra without extra scan. We propose to use the ΔB₀ map to correct the geometry distortion induced by B₀ field inhomogeneity in CEST-EPI. The effectiveness of DISC strategy for CEST-EPI was evaluated on a creatine phantom, healthy and tumor mice at 3 T, and AQP4 heterozygotes mice at 11.7 T. For both the original CEST images and the generated CEST contrast maps, the spatial improvement was first confirmed by the visual comparison and then quantitatively assessed by the structural similarity index measure (SSIM) comparison together with correlation analysis.</p><p><strong>Results: </strong>DISC-CEST-EPI showed higher SSIM and spatial consistency compared to CEST-EPI when using CEST-rapid acquisition with relaxation enhancement as a reference in vitro and in vivo at 3 T. For in vivo experiments at 11.7 T, SSIM values of amide proton transfer and relayed nuclear Overhauser effects maps of DISC-CEST-EPI were slightly higher than CEST-EPI and comparable with field-mapping and top-up.</p><p><strong>Conclusion: </strong>DISC-CEST-EPI can correct the distortion in CEST-EPI at 3 T, leading to improved SSIM and CEST quantification. This approach has the potential to enhance image quality and improve diagnostic accuracy for single-shot CEST-EPI at especially low-field MRI. However, the performance of DISC-CEST-EPI is limited at 11.7 T, and further advancements are necessary to enhance its functionality at ultra-high fields.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The contributions of aquaporin-4 to water exchange across the blood-brain barrier measured by filter-exchange imaging.","authors":"Zejun Wang, Shuyuan Tan, Keyu Lu, Qingcheng Li, Bingjie Jiao, Weiyun Li, Xuetao Wu, Lili Zhang, Linghui Zeng, Ruiliang Bai","doi":"10.1002/mrm.70049","DOIUrl":"https://doi.org/10.1002/mrm.70049","url":null,"abstract":"<p><strong>Purpose: </strong>Water exchange across the blood-brain barrier (WEX_BBB) is a promising biomarker for assessing the blood-brain barrier (BBB) integrity. However, the physiological mechanisms governing WEX_BBB remain unclear. This study was conducted to investigate the contribution of Na⁺/K⁺-ATPase (NKA) on the luminal side of endothelial cells and aquaporin-4 (AQP4) to WEX_BBB.</p><p><strong>Methods: </strong>WEX_BBB was measured using filter-exchange imaging for BBB assessment (FEXI-BBB) on rats, and data were fitted using an adapted two-compartment crusher-compensated exchange rate (CCXR) model. Test-retest reliability of the vascular water efflux rate constant (k_bo) was assessed. Ouabain and 2-(nicotinamide)-1,3,4-thiadiazole (TGN-020) were administered to inhibit NKA on the luminal side of endothelial cells and AQP4, respectively, to investigate their roles in WEX_BBB measured by FEXI-BBB.</p><p><strong>Results: </strong>Fixing intravascular diffusivity in the two-compartment CCXR model significantly improved estimation accuracy and precision of k_bo and other parameters. The test-retest experiment demonstrated that this method had good reproducibility in measuring k_bo (intraclass correlation coefficient = 0.79). Administering TGN-020, which inhibits AQP4, significantly decreased k_bo by 32% (k_bo = 3.07 ± 0.81 s^-1 vs. 2.09 ± 1.10 s^-1, p < 0.05). However, the ouabain-treated group showed no significant change in k_bo compared with that of the control group (2.51 ± 0.58 s^-1 vs. 2.37 ± 1.02 s^-1, p = 0.73) in the NKA inhibition experiment.</p><p><strong>Conclusions: </strong>WEX_BBB decreased by 32% after administering TGN-020, but no downward trend was noted after administering ouabain. Our findings indicate that AQP4 expression/function, but not NKA activity on the luminal side of endothelial cells, plays a significant role in regulating WEX_BBB.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Liver fat quantification at 0.55 T enabled by locally low-rank enforced deep learning reconstruction.","authors":"Majd Helo, Dominik Nickel, Stephan Kannengiesser, Thomas Kuestner","doi":"10.1002/mrm.70057","DOIUrl":"https://doi.org/10.1002/mrm.70057","url":null,"abstract":"<p><strong>Purpose: </strong>The emergence of new medications for fatty liver conditions has increased the need for reliable and widely available assessment of MRI proton density fat fraction (MRI-PDFF). Whereas low-field MRI presents a promising solution, its utilization is challenging due to the low SNR. This work aims to enhance SNR and enable precise PDFF quantification at low-field MRI using a novel locally low-rank deep learning-based (LLR-DL) reconstruction.</p><p><strong>Methods: </strong>LLR-DL alternates between regularized SENSE and a neural network (U-Net) throughout several iterations, operating on complex-valued data. The network processes the spectral projection onto singular value bases, which are computed on local patches across the echoes dimension. The output of the network is recast into the basis of the original echoes and used as a prior for the following iteration. The final echoes are processed by a multi-echo Dixon algorithm. Two different protocols were proposed for imaging at 0.55 T. An iron-and-fat phantom and 10 volunteers were scanned on both 0.55 and 1.5 T systems. Linear regression, t-statistics, and Bland-Altman analyses were conducted.</p><p><strong>Results: </strong>LLR-DL achieved significantly improved image quality compared to the conventional reconstruction technique, with a 32.7% increase in peak SNR and a 25% improvement in structural similarity index. PDFF repeatability was 2.33% in phantoms (0% to 100%) and 0.79% in vivo (3% to 18%), with narrow cross-field strength limits of agreement below 1.67% in phantoms and 1.75% in vivo.</p><p><strong>Conclusion: </strong>An LLR-DL reconstruction was developed and investigated to enable precise PDFF quantification at 0.55 T and improve consistency with 1.5 T results.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predictive signal modeling and multi-rate filtering in accelerated cardiac MRI.","authors":"Aaron D Curtis, Calder D Sheagren, Alexander J Mertens, Raviraj S Adve, Raymond H Kwong, Graham A Wright, Hai-Ling Margaret Cheng","doi":"10.1002/mrm.70058","DOIUrl":"https://doi.org/10.1002/mrm.70058","url":null,"abstract":"<p><strong>Purpose: </strong>True real-time cardiac MRI (CMR), necessary for capturing live cardiac dynamics and imaging irregular cardiac rhythms, remains challenging. In this article, we move toward real-time CMR in multiple reconstruction frameworks via strategies to predict cardiac motion, improve computational efficiency, reduce artifacts, and preserve spatial resolution.</p><p><strong>Theory and methods: </strong>A published predictive signal model (PMOT) for imaging irregular cardiac dynamics was modified (mPMOT) to enable efficient computation of state-transition matrices for predicting cardiac motion, as training PMOT is computationally expensive. A multi-rate Kalman filter framework was developed to enable computationally efficient reconstructions of high-resolution, large-matrix CMR datasets. Reconstructions were evaluated on multi-coil CMR data in human and swine using multi-rate Kalman filtering and compressed sensing (CS).</p><p><strong>Results: </strong>Training mPMOT is two orders of magnitude faster than PMOT. Across all datasets and frameworks, mPMOT facilitated high-quality reconstructions of CMR images for different undersampling patterns at acceleration factors of 9 and 13.5. Furthermore, mPMOT substantially reduced temporal blurring artifacts naturally present in CS reconstructions. In swine, mPMOT reduced the mean-squared error of the multi-rate Kalman filter by two orders of magnitude. The multi-rate Kalman filter implementation maintained spatial resolution while reducing computation time from 5439 s to 56 s in select applications.</p><p><strong>Conclusion: </strong>Our mPMOT is computationally efficient and can be integrated within multiple established reconstruction frameworks to ensure robust tracking and reconstruction for dynamic and real-time CMR applications.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A network-assisted joint image and motion estimation approach for robust 3D MRI motion correction across severity levels.","authors":"Brian Nghiem, Zhe Wu, Sriranga Kashyap, Lars Kasper, Kâmil Uludağ","doi":"10.1002/mrm.70052","DOIUrl":"https://doi.org/10.1002/mrm.70052","url":null,"abstract":"<p><strong>Purpose: </strong>The purpose of this work was to develop and evaluate a novel method that leverages neural networks and physical modeling for 3D motion correction at different levels of corruption.</p><p><strong>Methods: </strong>The novel method (\"UNet+JE\") combines an existing neural network (\"UNet_mag\") with a physics-informed algorithm for jointly estimating motion parameters and the motion-compensated image (\"JE\"). UNet_mag and UNet+JE were trained on two training datasets separately with different distributions of motion corruption severity and compared to JE as a benchmark. All five resulting methods were tested on T₁w 3D MPRAGE scans of healthy participants with simulated (n = 40) and in vivo (n = 10) motion corruption ranging from mild to severe motion.</p><p><strong>Results: </strong>UNet+JE provided better motion correction than UNet_mag ( <math> <semantics><mrow><mi>p</mi> <mo><</mo> <msup><mn>10</mn> <mrow><mo>-</mo> <mn>2</mn></mrow> </msup> </mrow> <annotation>$$ p<{10}^{-2} $$</annotation></semantics> </math> for all metrics for both simulated and in vivo data), under both training datasets. UNet_mag exhibited residual image artifacts and blurring, as well as greater susceptibility to data distribution shifts than UNet+JE. UNet+JE and JE did not significantly differ in image correction quality ( <math> <semantics><mrow><mi>p</mi> <mo>></mo> <mn>0.05</mn></mrow> <annotation>$$ p>0.05 $$</annotation></semantics> </math> for all metrics), even under strong distribution shifts for UNet+JE. However, UNet+JE reduced runtimes by a median reduction factor of between 2.00 to 3.80 as well as 4.05 for the simulation and in vivo studies, respectively.</p><p><strong>Conclusions: </strong>UNet+JE benefitted from the robustness of joint estimation and the fast image improvement provided by the neural network, enabling the method to provide high quality 3D image correction under a wide range of motion corruption within shorter runtimes.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cerebellar imaging for neuroscience at 9.4 T","authors":"","doi":"10.1002/mrm.70056","DOIUrl":"https://doi.org/10.1002/mrm.70056","url":null,"abstract":"","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"94 5","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mrm.70056","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144915116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}