Magnetic Resonance in Medicine最新文献

{"title":"Accelerated motion-robust abdominal 3D T1ρ mapping using diamond radial sampling.","authors":"Sandeep Panwar Jogi, Qi Peng, Ramin Jafari, Ricardo Otazo, Can Wu","doi":"10.1002/mrm.70079","DOIUrl":"https://doi.org/10.1002/mrm.70079","url":null,"abstract":"<p><strong>Purpose: </strong>To develop and validate a fast, motion-robust, free-breathing abdominal 3D T1ρ mapping method by combining variable-density diamond radial k-space sampling with fast-MAPSS (magnetization-prepared angle-modulated partitioned-k-space spoiled gradient-echo snapshots).</p><p><strong>Methods: </strong>3D MAPSS T1ρ imaging was performed at 3T using five spin-lock time (TSL) pairs in phantom scans and three TSL pairs in nine healthy volunteers. Phantom experiments compared Cartesian sampling (reference) with stack-of-stars and diamond radial sampling. Volunteer scans utilized stack-of-stars and diamond sampling. T1ρ values were calculated using mono-exponential fitting with MAPSS (five or three TSL pairs) and fast-MAPSS (three TSLs). These values were compared across sampling methods and T1ρ techniques in phantom and in vivo for the liver, pancreas, and muscles.</p><p><strong>Results: </strong>Diamond sampling achieved a 2.2-fold acceleration compared to stack-of-stars. In phantom experiments, mean T1ρ differences from reference Cartesian MAPSS were -1.93% for stack-of-stars, and -0.09% for diamond sampling. Fast-MAPSS with three TSLs resulted in differences of 0.54% (stack-of-stars) and 1.45% (diamond). In volunteers, a strong correlation (R² ≥ 0.88) was observed between diamond and stack-of-stars MAPSS, and between MAPSS and fast-MAPSS for both sampling methods. Bland-Altman analysis revealed minimal biases (<1.5 ms) between the methods. Paired t-tests indicated no significant T1ρ differences between MAPSS and fast-MAPSS or between sampling methods in volunteers.</p><p><strong>Conclusion: </strong>Fast-MAPSS with diamond radial k-space sampling enables clinically feasible, motion-robust, free-breathing 3D T1ρ mapping of the abdomen with reduced scan time and quantification accuracy comparable to standard methods.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145033450","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":"On the structural and practical identifiability of multi-echo BBB-ASL tracer kinetic models.","authors":"Tabitha J Manson, David L Thomas, Matthias Günther, Lynette J Tippett, Michael Dragunow, Catherine A Morgan, Vinod Suresh","doi":"10.1002/mrm.70075","DOIUrl":"https://doi.org/10.1002/mrm.70075","url":null,"abstract":"<p><strong>Purpose: </strong>Tracer kinetic models are used in arterial spin labeling (ASL); however, deciding which model parameters to fix or fit is not always trivial. The identifiability of the resultant system of equations is useful to consider, since it will likely impact parameter uncertainty. Here, we analyze the identifiability of two-compartment models used in multi-echo (ME) blood-brain-barrier (BBB)-ASL and evaluate the reliability of the fitted water-transfer rate <math> <semantics><mrow><mo>(</mo> <msub><mi>k</mi> <mi>w</mi></msub> </mrow> <annotation>$$ Big({k}_w $$</annotation></semantics> </math> ).</p><p><strong>Method: </strong>The identifiability of two variants of a two-compartment model (referred to here as \"series\" and \"parallel\") were analyzed using sensitivity matrix and Monte-Carlo simulation methods, the latter including the effects of noise and fixed-parameter error. ME-ASL data were collected at 3T in 25 cognitively normal participants (57-85 y). In one volunteer, additional scans were acquired to estimate noise. Fits for whole-gray-matter <math> <semantics> <mrow><msub><mi>k</mi> <mi>w</mi></msub> </mrow> <annotation>$$ {k}_w $$</annotation></semantics> </math> were performed with a theoretically identifiable version of the model.</p><p><strong>Results: </strong>All models needed one or more fixed parameters to be structurally identifiable, with different combinations required for each. Practical identifiability analysis yielded <math> <semantics> <mrow><msub><mi>k</mi> <mi>w</mi></msub> </mrow> <annotation>$$ {k}_w $$</annotation></semantics> </math> estimates with a median absolute error of 29% (parallel model) and 33% (series model). Fits to data yielded median <math> <semantics> <mrow><msub><mi>k</mi> <mi>w</mi></msub> </mrow> <annotation>$$ {k}_w $$</annotation></semantics> </math> values of 0 (parallel) and 96 min^-1 (series).</p><p><strong>Conclusion: </strong>We used identifiability analysis to determine an appropriate BBB-ASL model for acquired data. Through simulations we showed that parameter estimates depend on model selection and the value of fixed parameters. We demonstrated that fixed-parameter value and errors significantly impact the reliability of <math> <semantics> <mrow><msub><mi>k</mi> <mi>w</mi></msub> </mrow> <annotation>$$ {k}_w $$</annotation></semantics> </math> values obtained from acquired ME-ASL images, even with structurally identifiable models.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145033699","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":"Optimized reconstruction of undersampled Dixon sequences using new memory-efficient unrolled deep neural networks: HalfVarNet and HalfDIRCN.","authors":"Sandra Martin, Amira Trabelsi, Maxime Guye, Marc Dubois, Redha Abdeddaim, David Bendahan, Rémi André","doi":"10.1002/mrm.70070","DOIUrl":"https://doi.org/10.1002/mrm.70070","url":null,"abstract":"<p><strong>Purpose: </strong>Fat fraction (FF) quantification in individual muscles using quantitative MRI is of major importance for monitoring disease progression and assessing disease severity in neuromuscular diseases. Undersampling of MRI acquisitions is commonly used to reduce scanning time. The present paper introduces novel unrolled neural networks for the reconstruction of undersampled MRI acquisitions. These networks are designed with the aim of maintaining accurate FF quantification while reducing reconstruction time and memory usage.</p><p><strong>Methods: </strong>The proposed approach relies on a combination of a simplified architecture (Half U-Net) with unrolled networks that achieved high performance in the well-known FastMRI challenge (variational network [VarNet] and densely interconnected residual cascading network [DIRCN]). The algorithms were trained and evaluated using 3D MRI Dixon acquisitions of the thigh from controls and patients with neuromuscular diseases. The study was performed by applying a retrospective undersampling with acceleration factors of 4 and 8. Reconstructed images were used to computed FF maps.</p><p><strong>Results: </strong>Results disclose that the novel unrolled neural networks were able to maintain reconstruction, biomarker assessment, and segmentation quality while reducing memory usage by 24% to 16% and reducing reconstruction time from 21% to 17%. Using an acceleration factor of 8, the proposed algorithms, HalfVarNet and HalfDIRCN, achieved structural similarity index (SSIM) scores of 93.76 ± 0.38 and 94.95 ± 0.32, mean squared error (MSE) values of 12.76 ± 1.08 × 10^-2 and 10.25 ± 0.87 × 10^-2, and a relative FF quadratic error of 0.23 ± 0.02% and 0.17 ± 0.02%, respectively.</p><p><strong>Conclusion: </strong>The proposed method enables time and memory-efficient reconstruction of undersampled 3D MRI data, supporting its potential for clinical application.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145023609","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":"Free-breathing phase-sensitive inversion recovery T₁-weighted imaging for improved visualization of focal liver lesions.","authors":"Yavuz Muslu, Julius F Heidenreich, Jan-Peter Grunz, Ty A Cashen, Sagar Mandava, Ali Pirasteh, Diego Hernando, Scott B Reeder","doi":"10.1002/mrm.70042","DOIUrl":"https://doi.org/10.1002/mrm.70042","url":null,"abstract":"<p><strong>Purpose: </strong>Gadoxetic acid-enhanced hepatobiliary phase T₁-weighted (T₁w) MRI is effective for the detection of focal liver lesions but lacks sufficient T₁ contrast to distinguish benign from malignant lesions. Although the addition of T₂, diffusion, and dynamic contrast-enhanced T₁w imaging improves lesion characterization, these methods often do not provide adequate spatial resolution to identify subcentimeter lesions. This work proposes a high-resolution, volumetric, free-breathing liver MRI method that produces colocalized fat-suppressed, variable T₁w images from a single acquisition, thereby improving both lesion detection and characterization.</p><p><strong>Theory and methods: </strong>This method combines stack-of-stars radial sampling, magnetization preparation, and chemical shift encoding to enable free-breathing, T₁w imaging with water/fat separation. A model-based image reconstruction algorithm reconstructs images from highly undersampled k-space data. Pseudo-T₁ relaxation maps are calculated from the variable T₁w images. The feasibility of this method was investigated in patients undergoing clinical contrast-enhanced MRI examinations for detection and characterization of focal liver lesions at both 1.5 and 3.0 T. An expert reader study was conducted to evaluate the method's performance, compared with the hepatobiliary phase-navigated T₁w MRI based on image quality and lesion conspicuity.</p><p><strong>Results: </strong>Expert readers found that at shorter inversion times (TIs) (˜500 ms), the proposed method had superior liver-lesion contrast for characterizing simple cysts and metastases, compared with navigated T₁w images.</p><p><strong>Conclusion: </strong>The proposed method produces colocalized fat-suppressed, variable T₁w images from a single acquisition that may improve focal liver lesion detection and characterization.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145023593","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":"Simultaneous in vivo detection of spectrally resolved glutamate, glutamine, and glutathione at 3 T with NAA-aspartyl editing and echo-time optimization.","authors":"Li An, Sungtak Hong, Tara Turon, Adriana J Pavletic, Christopher S Johnson, Jun Shen","doi":"10.1002/mrm.70076","DOIUrl":"https://doi.org/10.1002/mrm.70076","url":null,"abstract":"<p><strong>Purpose: </strong>To achieve spectrally resolved in vivo detection of glutamate, glutamine, and glutathione at 3 T.</p><p><strong>Methods: </strong>Difference editing of N-acetylaspartate CH₂ protons (NAA-CH₂) combined with a new echo-time (TE) optimization approach is introduced. Difference editing was used to detect NAA-CH₂ independently of NAA-CH₃, thereby eliminating systematic errors arising from constrained fitting of the entire NAA molecule. Numerical optimization of TE and TE₁ minimized interference from highly dominant glutamate in glutamine detection in the ON/OFF sum spectrum. In vivo data were acquired from 6 healthy participants, including 2 who underwent oral administration of [U-¹³C]glucose.</p><p><strong>Results: </strong>The NAA-aspartyl-edited, cleaned-up in vivo spectrum showed distinct separation of glutamate, glutamine, and glutathione peaks at 3 T, facilitating spectral quantification and clinical applications. The post-¹³C proton MR-spectroscopy spectra clearly demonstrated the dynamic ¹³C-labeling of glutamate C4 following oral [U-¹³C]glucose intake.</p><p><strong>Conclusion: </strong>This technique enables simultaneous spectral resolution of glutamate, glutamine, and glutathione peaks at 3 T using difference editing of NAA-CH₂ and an optimized TE of 85 ms. Additionally, it demonstrates, for the first time, the feasibility of measuring ¹³C turnovers of spectrally resolved glutamate at 3 T with the high sensitivity and spatial resolution of proton MR spectroscopy.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145023552","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":"Outlook on zero/ultrashort echo time techniques in functional MRI.","authors":"Silvia Mangia, Shalom Michaeli, Olli Gröhn","doi":"10.1002/mrm.70065","DOIUrl":"10.1002/mrm.70065","url":null,"abstract":"<p><p>Since its introduction more than 30 years ago, the blood oxygenation level dependent (BOLD) contrast remains the most widely used method for functional MRI (fMRI) in humans and animal models. The BOLD contrast is typically acquired with echo planar imaging (EPI) to obtain sensitization of the signal during the echo time (TE) to dynamic changes in deoxyhemoglobin content, while achieving high spatiotemporal resolution and full brain coverage. However, EPI-based fMRI also faces multiple shortcomings, including sensitivity to body motion, susceptibility-related signal dropouts, interference with multimodal sensors, and loud acoustic noise. Here we provide a succinct overview and outlook of alternative strategies for fMRI relying on free induction decay–based techniques, which, by using zero/ultrashort TE, inherently solve most of these challenges. Such approaches are receiving increasing attention in the field of fMRI, motivated by initial findings in humans and animal models in which robust functional contrast was obtained despite the absence of an echo, primarily via sensitization to inflowing blood. We therefore discuss the benefits and current shortcomings of zero/ultrashort TE fMRI versus conventional EPI-based fMRI, the opportunities for enabling fMRI designs that are challenging with EPI-based approaches, and the state of progress toward use in clinical settings. Overall, zero/ultrashort TE fMRI is predicted to become a powerful new tool for basic, clinical, and preclinical research, especially for applications at ultrahigh magnetic fields, studies in awake animals, multimodal imaging, investigations requiring minimization of scanning noise, and fMRI beyond the brain.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145006332","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":"Sampling of non-Gaussian Ensemble Average Propagators for the simulation of diffusion magnetic resonance images.","authors":"Justino R Rodríguez-Galván, Pablo Villacorta-Aylagas, Susana Merino-Caviedes, Federico Simmross-Wattenberg, Carlos Castillo-Passi, Pablo Irarrazaval, Antonio Tristán-Vega, Carlos Alberola-López","doi":"10.1002/mrm.70080","DOIUrl":"https://doi.org/10.1002/mrm.70080","url":null,"abstract":"<p><strong>Purpose: </strong>(a) To design a methodology for drawing random samples of any Ensemble Average Propagator (EAP) (b) to modify the KomaMRI simulator to accommodate them as realistic spin movements to simulate diffusion MRI (dMRI) and (c) to compare these simulations with those based on the Diffusion Tensor (DT) model.</p><p><strong>Theory and methods: </strong>The rejection method is used for random sampling of EAPs: starting from a probability law that is easily sampled, and whose density function wraps the target EAP, samples are accepted when they lie inside the targeted region. This is used to sample the EAP as described by Mean Apparent Propagator MRI (MAP-MRI) and in Spherical Convolution (SC) based on Spherical Harmonics (SH). With this methodology, MAP-MRI and SC representations are calculated over in-vitro pig hearts images, and a simulation of a pulsed-gradient spin echo (PGSE) dMRI sequence inside the myocardial wall is undertaken with the KomaMRI simulator.</p><p><strong>Results: </strong>MAP-MRI shows better agreement with the actual acquisition than conventional DT-based simulations, in terms of Mean Squared Errors and correlation with improvements up to 1.7 % for the former and 2.2 % for the latter.</p><p><strong>Conclusion: </strong>dMRI sequences can be simulated accurately (yet, efficiently) if phantoms with a proper per-spin description of the diffusion process are made available. Moreover, our findings suggest that the study of non-Gaussian diffusion of the heart might be feasible, at least in vitro.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145006365","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":"Abdominal simultaneous 3D water T₁ and T₂ mapping using a free-breathing Cartesian acquisition with spiral profile ordering.","authors":"Jonathan Stelter, Kilian Weiss, Lisa Steinhelfer, Jakob Meineke, Weitong Zhang, Bernhard Kainz, Rickmer F Braren, Dimitrios C Karampinos","doi":"10.1002/mrm.70040","DOIUrl":"https://doi.org/10.1002/mrm.70040","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Purpose: &lt;/strong&gt;To develop a method for abdominal simultaneous 3D water &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {T}_1 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ( &lt;math&gt; &lt;semantics&gt;&lt;mrow&gt;&lt;mi&gt;w&lt;/mi&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ mathrm{w}{T}_1 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ) and &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {T}_2 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ( &lt;math&gt; &lt;semantics&gt;&lt;mrow&gt;&lt;mi&gt;w&lt;/mi&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ mathrm{w}{T}_2 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ) mapping with isotropic resolution using a free-breathing Cartesian acquisition with spiral profile ordering (CASPR) at 3 T.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;The proposed data acquisition combines a Look-Locker scheme with the modified BIR-4 adiabatic preparation pulse for simultaneous &lt;math&gt; &lt;semantics&gt;&lt;mrow&gt;&lt;mi&gt;w&lt;/mi&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ mathrm{w}{T}_1 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; and &lt;math&gt; &lt;semantics&gt;&lt;mrow&gt;&lt;mi&gt;w&lt;/mi&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ mathrm{w}{T}_2 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; mapping. CASPR is employed for efficient and flexible k-space sampling at isotropic resolution during free breathing. The imaging pipeline includes subspace reconstruction, water-fat separation, and &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {B}_0 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; -specific dictionary matching. The proposed method was validated in a water-fat relaxometry phantom using spin echo-based reference techniques and was compared with MOLLI &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {T}_1 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; and GRASE &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {T}_2 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; mapping in 10 volunteers. The method's flexibility was assessed at isotropic resolutions of 2.5, 3, and 3.5 mm, with corresponding scan times of 7:19, 5:23, and 3:52 min. Additionally, the method was applied to 9 oncological patients with abdominal pathologies.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Phantom experiments demonstrated good agreement between the proposed method and spin echo-based reference techniques across a wide range of &lt;math&gt; &lt;semantics&gt;&lt;mrow&gt;&lt;mi&gt;w&lt;/mi&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ mathrm{w}{T}_1 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; and &lt;math&gt; &lt;semantics&gt;&lt;mrow&gt;&lt;mi&gt;w&lt;/mi&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ mathrm{w}{T}_2 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; value","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145006376","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":"Characterizing the imaging environment for supine breast MRI.","authors":"Judith Zimmermann, Jana Vincent, Fraser Robb, Bruce L Daniel, Brian A Hargreaves, Catherine J Moran","doi":"10.1002/mrm.70029","DOIUrl":"https://doi.org/10.1002/mrm.70029","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Purpose: &lt;/strong&gt;Supine breast MRI has the potential to improve over standard prone breast magnetic resonance imaging (MRI) in terms of efficiency and image quality, image alignment with diagnostic and treatment procedures, and overall accessibility. This study aims to characterize potential technical challenges of imaging in the supine position: (i) &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {mathrm{B}}_0 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt;  field inhomogeneities, (ii) &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;/mrow&gt; &lt;/msubsup&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {mathrm{B}}_1^{+} $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt;  variations, (iii) respiratory-induced breast motion, and (iv) supine breast geometry.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Ten healthy subjects were scanned at 3T in both prone and supine positions to quantify and compare (i) and (ii) between both positions, and to assess (iii) in the supine position. Breast image volumes from a wider population (N = 40, healthy volunteers and patients) were analyzed to obtain breast shape metrics to characterize (iv).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;&lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {mathrm{B}}_0 $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt;  field inhomogeneity increased from prone positioning (2SD: &lt;math&gt; &lt;semantics&gt;&lt;mrow&gt;&lt;mn&gt;122&lt;/mn&gt; &lt;mspace&gt;&lt;/mspace&gt; &lt;mtext&gt;Hz&lt;/mtext&gt; &lt;mo&gt;±&lt;/mo&gt; &lt;mn&gt;25&lt;/mn&gt; &lt;mspace&gt;&lt;/mspace&gt; &lt;mtext&gt;Hz&lt;/mtext&gt;&lt;/mrow&gt; &lt;annotation&gt;$$ 122kern0.2em mathrm{Hz}pm 25kern0.2em mathrm{Hz} $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ) to supine positioning (2SD: &lt;math&gt; &lt;semantics&gt;&lt;mrow&gt;&lt;mn&gt;152&lt;/mn&gt; &lt;mspace&gt;&lt;/mspace&gt; &lt;mtext&gt;Hz&lt;/mtext&gt; &lt;mo&gt;±&lt;/mo&gt; &lt;mn&gt;15&lt;/mn&gt; &lt;mspace&gt;&lt;/mspace&gt; &lt;mtext&gt;Hz&lt;/mtext&gt;&lt;/mrow&gt; &lt;annotation&gt;$$ 152kern0.2em mathrm{Hz}pm 15kern0.2em mathrm{Hz} $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ), and &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;/mrow&gt; &lt;/msubsup&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {mathrm{B}}_1^{+} $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt;  flip angle variations (from prescribed &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;30&lt;/mn&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mo&gt;∘&lt;/mo&gt;&lt;/mrow&gt; &lt;/msup&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {30}^{circ } $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ) were greater in the supine position (2SD ranging &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;7&lt;/mn&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mo&gt;∘&lt;/mo&gt;&lt;/mrow&gt; &lt;/msup&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {7}^{circ } $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; to &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;13&lt;/mn&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mo&gt;∘&lt;/mo&gt;&lt;/mrow&gt; &lt;/msup&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {13}^{circ } $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ) than in the prone position (2SD ranging &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt; &lt;mrow&gt;&lt;mo&gt;∘&lt;/mo&gt;&lt;/mrow&gt; &lt;/msup&gt; &lt;/mrow&gt; &lt;annotation&gt;$$ {6}^{circ } $$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; to &lt;math&gt; &lt;semantics&gt; &lt;mrow&gt; &lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;8&lt;/mn&gt;&lt;/mrow&gt;","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145006330","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":"Summary from the 2025 International Society for Magnetic Resonance in Medicine workshop on body MRI: Unsolved problems and unmet needs.","authors":"Elizabeth M Hecht, Houchun Harry Hu, Suraj D Serai, Holden H Wu, Ryan L Brunsing, Alexander R Guimaraes, Sila Kurugol, Kristina I Ringe, Ali B Syed","doi":"10.1002/mrm.70055","DOIUrl":"https://doi.org/10.1002/mrm.70055","url":null,"abstract":"<p><p>In March of 2025, 145 attendees convened at the Hub for Clinical Collaboration of the Children's Hospital of Philadelphia for the inaugural International Society for Magnetic Resonance in Medicine (ISMRM) Body MRI Study Group workshop entitled \"Body MRI: Unsolved Problems and Unmet Needs.\" Approximately 24% of the attendees were MD or MD/PhD's, 45% were PhD's, and 30% were early-career trainees and postdoctoral associates. Among the invited speakers and moderators, 28% were from outside the United States, with a 40:60% female-to-male ratio. The 2.5-day program brought together a multidisciplinary group of scientists, radiologists, technologists, and trainees. Session topics included quantitative imaging biomarkers, low- and high-field strengths, artifact and motion correction, rapid imaging and focused protocols, and artificial intelligence. Another key session focused on the importance of team science and allowed speakers from academia and industry to share their personal experiences and offer advice on how to successfully translate new MRI technology into clinical practice. This article summarizes key points from the event and perceived unmet clinical needs within the field of body MRI.</p>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145000906","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}