Magnetic Resonance in Medicine最新文献

{"title":"<ArticleTitle xmlns:ns0=\"http://www.w3.org/1998/Math/MathML\"><ns0:math> <ns0:semantics> <ns0:mrow><ns0:msubsup><ns0:mi>B</ns0:mi> <ns0:mn>1</ns0:mn> <ns0:mo>+</ns0:mo></ns0:msubsup> </ns0:mrow> <ns0:annotation>$$ {mathrm{B}}_1^{+} $$</ns0:annotation></ns0:semantics> </ns0:math> mapping near metallic implants using turbo spin echo pulse sequences.","authors":"Iman Khodarahmi, Mary Bruno, Ran Schwarzkopf, Jan Fritz, Mahesh B Keerthivasan","doi":"10.1002/mrm.30491","DOIUrl":"https://doi.org/10.1002/mrm.30491","url":null,"abstract":"<p><strong>Purpose: </strong>To propose a B₁ ⁺ mapping technique for imaging of body parts containing metal hardware, based on magnitude images acquired with turbo spin echo (TSE) pulse sequences.</p><p><strong>Theory and methods: </strong>To encode the underlying B₁ ⁺, multiple (two to four) TSE image sets with various excitation and refocusing flip angles were acquired. To this end, the acquired signal intensities were matched to a database of simulated signals which was generated by solving the Bloch equations taking into account the exact sequence parameters. The retrieved B₁ ⁺ values were validated against gradient-recalled and spin echo dual angle methods, as well as a vendor-provided TurboFLASH-based mapping sequence, in gel phantoms and human subjects without and with metal implants.</p><p><strong>Results: </strong>In the absence of metal, phantom experiments demonstrated excellent agreement between the proposed technique using three or four flip angle sets and reference dual angle methods. In human subjects without metal implants, the proposed technique with three or four flip angle sets showed excellent correlation with the spin echo dual angle method. In the presence of metal, both phantoms and human subjects revealed a narrow range of B₁ ⁺ estimation with the reference techniques, whereas the proposed technique successfully resolved B₁ ⁺ near the metal. In select cases, the technique was implemented in conjunction with multispectral metal artifact reduction sequences and successfully applied for B₁ ⁺ shimming.</p><p><strong>Conclusion: </strong>The proposed technique enables resolution of B₁ ⁺ values in regions near metal hardware, overcoming susceptibility-related and narrow-range limitations of standard mapping techniques.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625485","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":"Denoising complex-valued diffusion MR images using a two-step, nonlocal principal component analysis approach.","authors":"Xinyu Ye, Xiaodong Ma, Ziyi Pan, Zhe Zhang, Hua Guo, Kamil Uğurbil, Xiaoping Wu","doi":"10.1002/mrm.30502","DOIUrl":"10.1002/mrm.30502","url":null,"abstract":"<p><strong>Purpose: </strong>To propose a two-step, nonlocal principal component analysis (PCA) method and demonstrate its utility for denoising complex diffusion MR images with a few diffusion directions.</p><p><strong>Methods: </strong>A two-step denoising pipeline was implemented to ensure accurate patch selection even with high noise levels and was coupled with data preprocessing for g-factor normalization and phase stabilization before data denoising with a nonlocal PCA algorithm. At the heart of our proposed pipeline was the use of a data-driven optimal shrinkage algorithm to manipulate the singular values in a way that would optimally estimate the noise-free signal. Our approach's denoising performances were evaluated using simulation and in vivo human data experiments. The results were compared with those obtained with existing local PCA-based methods.</p><p><strong>Results: </strong>In both simulation and human data experiments, our approach substantially enhanced image quality relative to the noisy counterpart, yielding improved performances for estimation of relevant diffusion tensor imaging metrics. It also outperformed existing local PCA-based methods in reducing noise while preserving anatomic details. It also led to improved whole-brain tractography relative to the noisy counterpart.</p><p><strong>Conclusion: </strong>The proposed denoising method has the utility for improving image quality for diffusion MRI with a few diffusion directions and is believed to benefit many applications, especially those aiming to achieve high-quality parametric mapping using only a few image volumes.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143615812","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":"T1234: A distortion-matched structural scan solution to misregistration of high resolution fMRI data.","authors":"Chung Kan, Rüdiger Stirnberg, Marcela Montequin, Omer Faruk Gulban, A Tyler Morgan, Peter A Bandettini, Laurentius Huber","doi":"10.1002/mrm.30480","DOIUrl":"10.1002/mrm.30480","url":null,"abstract":"<p><strong>Purpose: </strong>Registration of functional and structural data poses a challenge for high-resolution fMRI studies at 7 T. This study aims to develop a rapid acquisition method that provides distortion-matched, artifact-mitigated structural reference data.</p><p><strong>Methods: </strong>We introduce an efficient sequence protocol termed T1234, which offers adjustable distortions. This includes data that match distortions of functional data and data that are free of distortions. This approach involves a T₁-weighted 2-inversion 3D-EPI sequence with four combinations of read and phase encoding directions optimized for high-resolution fMRI. A forward Bloch model was used for T₁ quantification and protocol optimization. Fifteen participants were scanned at 7 T using both structural and functional protocols to evaluate the use of T1234.</p><p><strong>Results: </strong>Results from two protocols are presented. A fast distortion-free protocol reliably produced whole-brain segmentations at 0.8 mm isotropic resolution within 3:00-3:40 min. It demonstrates robustness across sessions, participants, and three different 7 T SIEMENS scanners. For a protocol with geometric distortions that matched functional data, T1234 facilitates layer-specific fMRI signal analysis with enhanced laminar precision.</p><p><strong>Conclusion: </strong>This structural mapping approach enables precise registration with fMRI data. T1234 has been successfully implemented, validated, and tested, and is now available to users at our center and at over 50 centers worldwide.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625403","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":"<ArticleTitle xmlns:ns0=\"http://www.w3.org/1998/Math/MathML\">Automated fibrosis segmentation from wideband post-contrast <ns0:math> <ns0:semantics> <ns0:mrow> <ns0:msubsup><ns0:mrow><ns0:mi>T</ns0:mi></ns0:mrow> <ns0:mrow><ns0:mn>1</ns0:mn></ns0:mrow> <ns0:mrow><ns0:mo>∗</ns0:mo></ns0:mrow> </ns0:msubsup> </ns0:mrow> <ns0:annotation>$$ {T}_1^{ast } $$</ns0:annotation></ns0:semantics> </ns0:math> mapping in an animal model of ischemic heart disease with implantable cardioverter-defibrillators.","authors":"Calder D Sheagren, Terenz Escartin, Jaykumar H Patel, Jennifer Barry, Graham A Wright","doi":"10.1002/mrm.30468","DOIUrl":"https://doi.org/10.1002/mrm.30468","url":null,"abstract":"<p><strong>Purpose: </strong>Post-contrast <math> <semantics> <mrow> <msubsup><mrow><mi>T</mi></mrow> <mrow><mn>1</mn></mrow> <mrow><mo>∗</mo></mrow> </msubsup> </mrow> <annotation>$$ {T}_1^{ast } $$</annotation></semantics> </math> mapping has proven promising for automated scar segmentation in subjects without ICDs, but this has not been implemented in patients with ICDs. We introduce an automated cluster-based thresholding method for <math> <semantics> <mrow> <msubsup><mrow><mi>T</mi></mrow> <mrow><mn>1</mn></mrow> <mrow><mo>∗</mo></mrow> </msubsup> </mrow> <annotation>$$ {T}_1^{ast } $$</annotation></semantics> </math> maps with an ICD present and compare it to manually tuned thresholding of synthetic LGE images with an ICD present and standard LGE without an ICD present.</p><p><strong>Methods: </strong>Seven swine received an ischemia-reperfusion myocardial infarction and were imaged at 3 T 4-5 weeks post-infarct with and without an ICD. Mapping-based thresholding was performed using synthetic LGE and artifact-corrected cluster-thresholding methods, both employing connected component filtering. Standard pixel signal intensity thresholding was performed on the conventional LGE without an ICD. Volumetric accuracy is relative to conventional LGE and Dice similarity between SynLGE and cluster-based segmentations were evaluated.</p><p><strong>Results: </strong>No statistical significance was observed between LGE volumes without an ICD and both SynLGE and artifact-corrected cluster-threshold volumes with an ICD, when using connected component filtering. Additionally, Dice alignment between SynLGE and cluster-thresholding was high for healthy myocardium (0.96), dense scar (0.83), and dense scar union gray zone (0.91) when artifact correction and connected component filtering were implemented.</p><p><strong>Conclusion: </strong>Clustering of <math> <semantics> <mrow> <msubsup><mrow><mi>T</mi></mrow> <mrow><mn>1</mn></mrow> <mrow><mo>∗</mo></mrow> </msubsup> </mrow> <annotation>$$ {T}_1^{ast } $$</annotation></semantics> </math> maps holds promise for a reproducible approach to scar segmentation in the presence of ICDs.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597376","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":"Elastographic magnetization prepared imaging with rapid encoding.","authors":"Alex M Cerjanic, Alexa M Diano, Curtis L Johnson","doi":"10.1002/mrm.30482","DOIUrl":"https://doi.org/10.1002/mrm.30482","url":null,"abstract":"<p><strong>Purpose: </strong>To introduce a novel sequence for achieving fast, whole-brain MR elastography data through the introduction of a magnetization preparation block for motion encoding along with rapid imaging readouts.</p><p><strong>Theory and methods: </strong>We implemented MRE motion encoding in a magnetization preparation pulse sequence block, where spins are excited, motion encoded, and then stored longitudinally. This magnetization is accessed through a train of rapid gradient echoes and encoded with a 3D stack-of-spirals trajectory. Spoilers are included to crush unprepared magnetization and avoid image artifacts. We demonstrate the feasibility of the proposed method in capturing MRE displacement data for estimating mechanical properties and accelerating scan times.</p><p><strong>Results: </strong>We measured stability of phase across gradient echo readouts in the readout train after magnetization preparation. Additionally, we obtained displacement fields with high OSS-SNR with retrospective sampling and differences in average stiffness properties (NRMSE) of 3.6% ( <math> <semantics> <mrow> <msub><mrow><mi>R</mi></mrow> <mrow><mi>x</mi> <mi>y</mi></mrow> </msub> <mo>=</mo> <mn>2</mn></mrow> <annotation>$$ {R}_{xy}=2 $$</annotation></semantics> </math> ) and 7.7% ( <math> <semantics> <mrow> <msub><mrow><mi>R</mi></mrow> <mrow><mi>x</mi> <mi>y</mi></mrow> </msub> <mo>=</mo> <mn>4</mn></mrow> <annotation>$$ {R}_{xy}=4 $$</annotation></semantics> </math> ) between retrospectively undersampled and fully sampled data. Prospective undersampling showed highly similar multiscale similarity measures and global property differences between 1.0% to 3.5% with one outlier of 8.1% between the proposed method and reference EPI scans.</p><p><strong>Conclusion: </strong>Magnetization preparation for MRE is feasible and can accelerate brain MRE scans, producing high-quality mechanical property maps at 2.5 mm isotropic resolution in 1 min 20 s.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597378","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":"Ultra-high temporal resolution 4D angiography using arterial spin labeling with subspace reconstruction","authors":"","doi":"10.1002/mrm.30496","DOIUrl":"https://doi.org/10.1002/mrm.30496","url":null,"abstract":"","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"93 5","pages":"C1"},"PeriodicalIF":3.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mrm.30496","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143595297","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}

{"title":"Real-time fetal brain and placental T2* mapping at 0.55T MRI.","authors":"Jordina Aviles Verdera, Sara Neves Silva, Kelly M Payette, Raphael Tomi-Tricot, Megan Hall, Lisa Story, Shaihan J Malik, Joseph V Hajnal, Mary A Rutherford, Jana Hutter","doi":"10.1002/mrm.30497","DOIUrl":"https://doi.org/10.1002/mrm.30497","url":null,"abstract":"<p><strong>Purpose: </strong>To provide real-time, organ-specific quantitative information - specifically placental and fetal brain T2 * - to optimize and personalize fetal MRI examinations.</p><p><strong>Methods: </strong>A low-latency setup enables real-time processing, including segmentation, T2* fitting, and centile calculation. Two nnU-Nets were trained on 2 989 fetal brains, and 540 placental datasets for automatic segmentation. Normative T2* curves over gestation were derived from 88 healthy cases. Prospective testing included 50 fetal MRI scans: A validation cohort (10 exams with three intra-scan repetitions) and an evaluation cohort (40 participants). Validation was performed with Bland-Altman assessments and Dice coefficients between repetitions, manual/automatic segmentations, and online/offline quantification.</p><p><strong>Results: </strong>T2* maps and centiles for the fetal brain and placenta were available in under one minute for all cases. The validation cohort showed robust reproducibility, with intra-scan mean T2* differences of 1.04, -3.17, and 5.07 ms for the fetal brain and -3.15, 4.74, and 2.45 ms for the placenta. Mean T2* differences between online and offline processing were 1.63 ms and 0.16 ms for the fetal brain and placenta, respectively. Dice coefficients were <math> <semantics><mrow><mn>0</mn> <mo>.</mo> <mn>84</mn> <mo>±</mo> <mn>0</mn> <mo>.</mo> <mn>02</mn></mrow> <annotation>$$ 0.84pm 0.02 $$</annotation></semantics> </math> for the placenta and <math> <semantics><mrow><mn>0</mn> <mo>.</mo> <mn>96</mn> <mo>±</mo> <mn>0</mn> <mo>.</mo> <mn>01</mn></mrow> <annotation>$$ 0.96pm 0.01 $$</annotation></semantics> </math> for the fetal brain.</p><p><strong>Conclusions: </strong>Real-time quantitative imaging supports personalized MR exams, optimizing sequence selection and working towards reducing recall rates. The ability to assess T2*, a potential biomarker for pregnancy complications, in real-time opens new clinical possibilities. Future research will apply this pipeline to pregnancies affected by preeclampsia and growth restriction and explore MR-guided fetal interventions.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597033","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":"Interleaved ²³Na/¹H MRI of the human heart at 7 T using a combined ²³Na/¹H coil setup and ¹H parallel transmission.","authors":"Laurent Ruck, Nico Egger, Tobias Wilferth, Judith Schirmer, Lena Vanessa Gast, Sophia Nagelstraßer, Saskia Wildenberg, Andreas Bitz, Titus Lanz, Tanja Platt, Simon Konstandin, Christoph Kopp, Michael Uder, Armin Michael Nagel","doi":"10.1002/mrm.30426","DOIUrl":"https://doi.org/10.1002/mrm.30426","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the feasibility of interleaved ²³Na/¹H cardiac MRI at 7 T using ¹H parallel transmission (pTx) pulses.</p><p><strong>Methods: </strong>A combined setup consisting of a ²³Na volume coil and two ¹H transceiver arrays was employed and the transmit and receive characteristics were compared in vitro with those of the uncombined radiofrequency coils. Furthermore, the implemented interleaved ²³Na/¹H pTx sequence was validated in phantom measurements and applied to four healthy subjects. For the latter, three customized ¹H excitation pulses (universal and individual phase shims (UPS/IPS) and individual 4kT pulses (4kT)) were employed in the interleaved ²³Na/¹H pTx sequence and compared with the vendor-provided default cardiac phase shim (DPS).</p><p><strong>Results: </strong>Combining both coils resulted in a reduction of the mean ²³Na transmit field (B₁ ⁺) efficiency and ²³Na signal-to-noise ratio by 18.9% and 15.4% for the combined setup, whereas the ¹H B₁ ⁺ efficiency was less influenced (-4.7%). Compared with single-nuclear acquisitions, interleaved dual-nuclear ²³Na/¹H MRI showed negligible influence on ²³Na and ¹H image quality. For all three customized ¹H pTx pulses the B₁ ⁺ homogeneity was improved (coefficients of variation: CV_UPS = 0.30, CV_IPS = 0.23, CV_4kT = 0.15) and no ¹H signal dropouts occurred compared with the vendor-provided default phase shim (CV_DPS = 0.37).</p><p><strong>Conclusion: </strong>The incorporation of customized ¹H pTx pulses in an interleaved ²³Na/¹H sequence scheme was successfully demonstrated at 7 T and improvements of the ¹H B₁ ⁺ homogeneity within the heart were shown. Combining interleaved ²³Na/¹H MRI with ¹H pTx is an important tool to enable robust quantification of myocardial tissue sodium concentrations at 7 T within clinically acceptable acquisition times.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597012","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":"High-resolution, volumetric diffusion-weighted MR spectroscopic imaging of the brain.","authors":"Zepeng Wang, Bradley P Sutton, Fan Lam","doi":"10.1002/mrm.30479","DOIUrl":"https://doi.org/10.1002/mrm.30479","url":null,"abstract":"<p><strong>Purpose: </strong>To achieve high-resolution, three-dimensional (3D) quantitative diffusion-weighted MR spectroscopic imaging (DW-MRSI) for molecule-specific microstructural imaging of the brain.</p><p><strong>Methods: </strong>We introduced and integrated several innovative acquisition and processing strategies for DW-MRSI: (a) a new double-spin-echo sequence combining selective excitation, bipolar diffusion encoding, rapid spatiospectral sampling, interleaved water spectroscopic imaging data, and a special sparsely sampled echo-volume-imaging (EVI)-based navigator, (b) a rank-constrained time-resolved reconstruction from the EVI data to capture spatially varying phases, (c) a model-based phase correction for DW-MRSI data, and (d) a multi-b-value subspace-based method for water/lipids removal and spatiospectral reconstruction using learned metabolite subspaces, and e) a hybrid subspace and parametric model-based parameter estimation strategy. Phantom and in vivo experiments were performed to validate the proposed method and demonstrate its ability to map metabolite-specific diffusion parameters in 3D.</p><p><strong>Results: </strong>The proposed method generated reproducible metabolite diffusion coefficient estimates, consistent with those from a standard single-voxel DW spectroscopy (SV-DWS) method. High-SNR multi-molecular mean diffusivity (MD) maps can be obtained at a 6.9  <math> <semantics><mrow><mo>×</mo></mrow> <annotation>$$ times $$</annotation></semantics> </math> 6.9 <math> <semantics><mrow><mo>×</mo></mrow> <annotation>$$ times $$</annotation></semantics> </math> 7.0 mm <math> <semantics> <mrow> <msup><mrow><mo> </mo></mrow> <mn>3</mn></msup> </mrow> <annotation>$$ {}^3 $$</annotation></semantics> </math> nominal resolution with large 3D brain coverage. High-resolution (4.4 <math> <semantics><mrow><mo>×</mo></mrow> <annotation>$$ times $$</annotation></semantics> </math> 4.4 <math> <semantics><mrow><mo>×</mo></mrow> <annotation>$$ times $$</annotation></semantics> </math> 5.6 mm <math> <semantics> <mrow> <msup><mrow><mo> </mo></mrow> <mrow><mn>3</mn></mrow> </msup> </mrow> <annotation>$$ {}^3 $$</annotation></semantics> </math> ) metabolite and diffusion coefficient maps can be obtained within 20 mins for the first time. Tissue-dependent metabolite MDs were observed, i.e., larger MDs for NAA, creatine, and choline in white matter than gray matter, with region-specific differences.</p><p><strong>Conclusion: </strong>We demonstrated an unprecedented capability of simultaneous, high-resolution metabolite and diffusion parameter mapping. This imaging capability has strong potential to offer richer molecular and tissue-compartment-specific microstructural information for various clinical and neuroscience applications.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143596920","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":"Toward optimal inline respiratory motion correction for in vivo cardiac diffusion tensor MRI using symmetric and inverse-consistent deformable image registration.","authors":"Yuchi Liu, Danielle Kara, Thomas Garrett, Shi Chen, Daniel Wee, Ning Jin, Peter Speier, Hiroshi Nakagawa, Pasquale Santangeli, Michael A Bolen, Oussama Wazni, Mazen Hanna, W H Wilson Tang, Animesh Tandon, Deborah Kwon, Xiaoming Bi, Christopher Nguyen","doi":"10.1002/mrm.30485","DOIUrl":"https://doi.org/10.1002/mrm.30485","url":null,"abstract":"<p><strong>Purpose: </strong>This study aims to develop a free-breathing cardiac DTI method with fast and robust motion correction.</p><p><strong>Methods: </strong>Two proposed image registration-based motion correction (MOCO) strategies, MOCO_Naive and MOCO_Avg, were applied to diffusion-weighted images acquired with M2 diffusion gradients under free-breathing. The effectiveness of MOCO was assessed by tracking epicardium pixel positions across image frames. Resulting mean diffusivity (MD), fractional anisotropy (FA), and helix angle (HA) maps were compared against a previous low rank tensor based MOCO method (MOCO_LRT) in 20 healthy volunteers and two patients scanned at 3 T.</p><p><strong>Results: </strong>Compared with the MOCO_LRT method, both proposed MOCO_Naive and MOCO_Avg methods generated slightly lower MD and helix angle transmurality (HAT) magnitude values, and significantly lower FA values. Moreover, both proposed MOCO methods achieved significantly smaller SDs of MD and FA values, and more smoothly varying helical structure in HA maps in healthy volunteers, indicating more effective MOCO. Elevated MD, decreased FA, and lower HAT magnitude were observed in two patients compared with healthy volunteers. Furthermore, the computing speed of image registration-based MOCO is twice as fast as the LRT method on the same dataset and same workstation.</p><p><strong>Conclusion: </strong>This study demonstrates a fast and robust motion correction approach using image registration for in vivo free-breathing cardiac DTI. It improves the quality of quantitative diffusion maps and will facilitate clinical translation of cardiac DTI.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597091","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}