Magnetic Resonance in Medicine最新文献

{"title":"A straightforward approach for 3D single-shot arterial spin labeling-based brain perfusion imaging: Preventing artifacts due to signal fluctuations","authors":"Dan Zhu,&nbsp;Feng Xu,&nbsp;Dapeng Liu,&nbsp;Qin Qin","doi":"10.1002/mrm.30439","DOIUrl":"10.1002/mrm.30439","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>The present work aims to evaluate the performance of three-dimensional (3D) single-shot stack-of-spirals turbo FLASH (SOS-TFL) acquisition for pseudo-continuous arterial spin labeling (PCASL) and velocity-selective ASL (VSASL)–based cerebral blood flow (CBF) mapping, as well as VSASL-based cerebral blood volume (CBV) mapping.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Digital phantom simulations were conducted for both multishot echo planar imaging and spiral trajectories with intershot signal fluctuations. PCASL-derived CBF (PCASL-CBF), VSASL-derived CBF (VSASL-CBF), and CBV (VSASL-CBV) were all acquired using 3D multishot gradient and spin-echo and SOS-TFL acquisitions following background suppression. Both simulation and in vivo images were compared between multishot and single-shot compressed sensing–regularized sensitivity encoding (CS-SENSE) reconstructions.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Artifacts were observed in both simulated multishot echo planar imaging and spiral readouts, as well as in in vivo multishot ASL perfusion images. A high correlation was found between the levels of signal fluctuations among interleaves and the severity of artifacts in both simulated and in vivo data. Image artifacts were more apparent in the inferior region of the brain, especially in CBF scans. These artifacts were effectively eliminated when single-shot CS-SENSE reconstruction was applied to the same data set.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>ASL images obtained from 3D segmented gradient and spin-echo or SOS-TFL acquisitions can exhibit artifacts caused by signal fluctuations among different shots, which persist even after the application of background suppression pulses. In contrast, these artifacts were prevented when single-shot CS-SENSE reconstruction was applied to the same SOS-TFL data set.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"93 6","pages":"2488-2498"},"PeriodicalIF":3.0,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143066503","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":"Rapid quantitative MRI at 46 mT: Accelerated T1 and T2 mapping with low-rank reconstructions","authors":"Yiming Dong,&nbsp;Chloé Najac,&nbsp;Matthias J. P. van Osch,&nbsp;Andrew Webb,&nbsp;Peter Börnert,&nbsp;Beatrice Lena","doi":"10.1002/mrm.30442","DOIUrl":"10.1002/mrm.30442","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>To evaluate accelerated T₁- and T₂-mapping techniques for ultra–low-field MRI using low-rank reconstruction methods.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Two low-rank–based algorithms, image-based locally low-rank (LLR) and k-space–based structured low-rank (SLR), were implemented to accelerate T₁ and T₂ mapping on a 46 mT Halbach MRI scanner. Data were acquired with 3D turbo spin-echo sequences using variable-density poisson-disk random sampling patterns. For validation, phantom and in vivo experiments were performed on six healthy volunteers to compare the obtained values with literature and to study reconstruction performance at different undersampling factors and spatial resolutions. In addition, the reconstruction performance of the LLR and SLR algorithms for T₁ mapping was compared using retrospective undersampling datasets. Total scan times were reduced from 45/38 min (R = 1) to 23/19 min (R = 2) and 11/9 min (R = 4) for a 2.5 × 2.5 × 5 mm³ resolution, and to 18/16 min (R = 4) for a higher in-plane resolution 1.5 × 1.5 × 5 mm³ for T₁/T₂ mapping, respectively.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Both LLR and SLR algorithms successfully reconstructed T₁ and T₂ maps from undersampled data, significantly reducing scan times and eliminating undersampling artifacts. Phantom validation showed that consistent T₁ and T₂ values were obtained at different undersampling factors up to R = 4. For in vivo experiments, comparable image quality and estimated T₁ and T₂ values were obtained for fully sampled and undersampled (R = 4) reconstructions, both of which were in line with the literature values.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The use of low-rank reconstruction allows significant acceleration of T₁ and T₂ mapping in low-field MRI while maintaining image quality.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"94 1","pages":"119-133"},"PeriodicalIF":3.0,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mrm.30442","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143066509","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":"Comparison of water exchange measurements between filter-exchange imaging and diffusion time-dependent kurtosis imaging in the human brain","authors":"Zhaoqing Li,&nbsp;Chunjing Liang,&nbsp;Qingping He,&nbsp;Thorsten Feiweier,&nbsp;Yi-Cheng Hsu,&nbsp;Jianhua Li,&nbsp;Ruiliang Bai","doi":"10.1002/mrm.30454","DOIUrl":"10.1002/mrm.30454","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>Filter-exchange imaging (FEXI) and diffusion time (t)-dependent kurtosis imaging (DKI(t)) are two diffusion-based methods that have been proposed for in vivo measurements of water exchange rates. Few studies have directly compared these methods. We aimed to investigate whether FEXI and DKI(t) yield comparable water exchange measurements in the human brain in vivo.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Eight healthy volunteers underwent multiple-direction FEXI and DKI(t) acquisitions on a 3T scanner. We performed region of interest (ROI) analysis to determine correlations between FEXI-derived apparent exchange rate (AXR) and DKI(t)-derived reciprocal of exchange time (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1</mn>\u0000 <mo>/</mo>\u0000 <msub>\u0000 <mi>τ</mi>\u0000 <mi>ex</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ 1/{tau}_{ex} $$</annotation>\u0000 </semantics></math>).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In both white matter (WM) and gray matter (GM), DKI(t) revealed substantial diffusion-time dependence of diffusivity and kurtosis. However, at <i>t</i> ≥ 100 ms, the diffusivity showed weak time dependence. In WM, this time dependence may be due to water exchange between myelin water and “free” water with different T₁ values, although other factors, such as remaining restrictive effects from microstructural barriers, cannot be excluded. We found a significant correlation between DKI(t)-derived <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1</mn>\u0000 <mo>/</mo>\u0000 <msub>\u0000 <mi>τ</mi>\u0000 <mi>ex</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ 1/{tau}_{ex} $$</annotation>\u0000 </semantics></math> and FEXI-derived AXR in the axial direction within WM. No such correlation was present in GM, although both values showed similar ranges.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>These results suggest that FEXI and DKI(t) could be sensitive to the same water exchange process only when the diffusion time in DKI(t) is sufficiently long, and only in WM. In both GM and WM, the restrictive effect of microstructure is non-negligible, especially at short diffusion times (&lt;100 ms).</p>\u0000 </section>\u0000 </div>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"93 6","pages":"2357-2369"},"PeriodicalIF":3.0,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143066507","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 whole-brain and cervical spine imaging at 7 T using a neurovascular head and neck coil with 8-channel transceiver array and 56-channel receiver array","authors":"Divya Baskaran,&nbsp;Belinda Ding,&nbsp;Son Chu,&nbsp;Paul McElhinney,&nbsp;Sarah Allwood-Spiers,&nbsp;Sydney N. Williams,&nbsp;Keith Muir,&nbsp;Natasha Eileen Fullerton,&nbsp;David Andrew Porter,&nbsp;Shajan Gunamony","doi":"10.1002/mrm.30450","DOIUrl":"10.1002/mrm.30450","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Purpose&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;To develop a 7T neurovascular head and neck (NVHN) coil with an extended longitudinal coverage of the brain and cervical spine, with eight transceiver (TxRx) channels and 56 receive (Rx) channels for dynamic parallel-transmit (pTx) applications.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Methods&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;A dual-row transceiver array with six elements in the upper row and two elements in the lower row was designed using combined electromagnetic and circuit optimization and constructed. A 56Rx array covering the brain and cervical spine was designed and combined with the transceiver array. The performance of the 8TxRx56Rx NVHN coil such as &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;mo&gt;+&lt;/mo&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{B}}_1^{+} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, signal-to-noise ratio, and g-factor were validated in phantom and in vivo studies and compared with an in-house 8Tx64Rx head coil. High-resolution in vivo images were acquired with the NVHN and head coil.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Results&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;The average &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;mo&gt;+&lt;/mo&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{B}}_1^{+} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; in phantom while exciting the upper six channels and all eight channels are 43.45 nT/V and 45.80 nT/V, respectively, demonstrating that the available &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;mo&gt;+&lt;/mo&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{B}}_1^{+} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; field is seamlessly distributed in the brain and/or cervical spine, depending on the chosen excitation. The 8TxRx56Rx NVHN coil increases the SNR in the cervical spine and central brain by a factor of 2.18 and 1.16, respectively, compared with the 8Tx64Rx head coil. Furthermore, it demonstrates similar 1/g-factor performance for acce","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"94 1","pages":"386-400"},"PeriodicalIF":3.0,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mrm.30450","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143066511","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":"Transient shear wave elastometry using a portable magnetic resonance sensor","authors":"William Selby,&nbsp;Phil Garland,&nbsp;Igor Mastikhin","doi":"10.1002/mrm.30444","DOIUrl":"10.1002/mrm.30444","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>Magnetic resonance elastography (MRE) provides detailed maps of tissue stiffness, helping to diagnose various health conditions, but requires the use of expensive clinical MRI scanners. Our approach utilizes compact, cost-effective portable MR sensors that offer bulk characterization of material properties in a region of interest close to the surface (within 1–2 cm). This accessible instrument could enable routine monitoring and prevention of diseases not readily evaluated with conventional tools.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The method was tested on tissue-mimicking phantoms with varying stiffness. The gels were excited with acoustic pulses (one cycle of a sinusoidal waveform) at a fixed distance from the MR sensor. A series of delays between acoustic excitation and MR signal detection allowed time for the pulse to travel to the sensitive region.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The “arrival time” of the shear wave, determined by the time-dependent MR signal response, was used to calculate the shear wave speed. MR measurements of shear wave speed were compared with optical sensor measurements and manufacturer-tabulated values, aligning with expected relative differences between samples.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>A portable MR-based transient elastometry technique for measuring tissue elasticity was developed and demonstrated on tissue-mimicking phantoms. Future improvements include using a new portable magnet to investigate depth-dependent changes in elasticity in stratified samples and integrating MR relaxation and diffusion measurements for comprehensive tissue analysis. This approach can complement conventional MRE in applications where a portable, affordable, and localized assessment of tissue stiffness is required.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"94 1","pages":"373-385"},"PeriodicalIF":3.0,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143052921","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":"Nexus: A versatile console for advanced low-field MRI","authors":"David Schote,&nbsp;Berk Silemek,&nbsp;Thomas O'Reilly,&nbsp;Frank Seifert,&nbsp;Jan-Lukas Assmy,&nbsp;Christoph Kolbitsch,&nbsp;Andrew G. Webb,&nbsp;Lukas Winter","doi":"10.1002/mrm.30406","DOIUrl":"10.1002/mrm.30406","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>To develop a low-cost, high-performance, versatile, open-source console for low-field MRI applications that can integrate a multitude of different auxiliary sensors.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A new MR console was realized with four transmission and eight reception channels. The interface cards for signal transmission and reception are installed in PCI Express slots, allowing console integration in a commercial PC rack. Following standards developed by the MRI community, we implemented an open-source console software package with native Pulseq and ISMRM raw data support. It is implemented in <i>Python</i> to allow easy customization and provide the flexible use of a freely configurable number of transmit and receive channels. We benchmarked the system by comparing the imaging quality with a state-of-the-art reference system. Different examples of how auxiliary sensors, connected via additional channels, can improve imaging are demonstrated.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Using a three-dimensional turbo spin-echo sequence, image quality of proton density–weighted and T₂-weighted images in the brain of a healthy volunteer obtained by the proposed Nexus console matches closely to a commonly applied commercial system. The use of additional receive channels was demonstrated for system monitoring (radiofrequency pulses and gradient currents), electromagnetic interference detection, and temperature and B₀ field monitoring. Based on these measurements, system calibrations and electromagnetic interference–mitigation techniques were applied to improve image quality.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Our console offers high versatility in terms of data acquisition, is freely configurable, adheres to open-source data standards, and is easy to customize. It yields a similar image quality compared with a commercially available reference system yet is substantially lower cost and open source.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"93 5","pages":"2224-2238"},"PeriodicalIF":3.0,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mrm.30406","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143052917","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":"Rapid prospective motion correction using free induction decay and stationary field probe navigators at 7T","authors":"Matthias Serger,&nbsp;Rüdiger Stirnberg,&nbsp;Philipp Ehses,&nbsp;Tony Stöcker","doi":"10.1002/mrm.30441","DOIUrl":"10.1002/mrm.30441","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>MR-based FID navigators (FIDnavs) do not require gradient pulses and are attractive for prospective motion correction (PMC) due to short acquisition times and high sampling rates. However, accuracy and precision are limited and depend on a separate calibration measurement. Besides FIDnavs, stationary NMR field probes are also capable of measuring local, motion-induced field changes. In this work, a linear model is calibrated between field probe data and motion parameters analog to FIDnav calibration and both tracking methods are compared and combined for PMC.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>FIDnavs and field probe navigators were implemented in a fast 3D-EPI sequence and calibrated by a linear model to realignment motion parameters of the 3D-EPI time series. A workflow was established to correct head motion prospectively by FIDnavs, field probe navigators or a combination of both. Large motions were instructed to test the accuracy and the impact on image quality in <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1</mn>\u0000 <mspace></mspace>\u0000 <msup>\u0000 <mtext>mm</mtext>\u0000 <mn>3</mn>\u0000 </msup>\u0000 </mrow>\u0000 <annotation>$$ 1kern0.1667em {mathrm{mm}}^3 $$</annotation>\u0000 </semantics></math> EPI data.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In a group of five subjects, FIDnavs demonstrated approximately doubled accuracy and precision in comparison with field probe navigators for large motions, especially nodding motions were tracked less accurately by field probes. A combination of both methods could not improve the accuracy consistently. Motion artifacts in high-resolution data were reduced similarly by both PMC methods, although artifacts remained due to susceptibility-induced B0 changes.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Stationary field probe navigators can be calibrated equivalently as FIDnavs and enable rapid PMC of large and fast motions. Although they reveal decreased accuracy, their contrast-independence facilitates the potential insertion into many sequences.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"94 1","pages":"105-118"},"PeriodicalIF":3.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mrm.30441","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143024037","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":"MRI detects tubulointerstitial changes in mouse models of radiation-induced nephropathy","authors":"Julia Stabinska,&nbsp;Joe Piccolo,&nbsp;Anupriya Chhabra,&nbsp;Ioanna Liatsou,&nbsp;Kathy Gabrielson,&nbsp;Zhi Li,&nbsp;Zinia Mohanta,&nbsp;Farzad Sedaghat,&nbsp;Robert F. Hobbs,&nbsp;George Sgouros,&nbsp;Michael T. McMahon","doi":"10.1002/mrm.30443","DOIUrl":"10.1002/mrm.30443","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>We hypothesized that radiation-induced tubulointerstitial changes in the kidney can be assessed using MRI-based T₂ relaxation time measurements.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We performed MRI, histology, and serum biochemistry in two mouse models of radiation nephropathy: one involving external beam radiotherapy and the other using internal irradiation with an α-particle-emitting actinium-225 radiolabeled antibody. We compared the mean T₂ values of different renal compartments between control and external beam radiotherapy or α-particle-emitting actinium-225 radiolabeled antibody–treated groups and between the two radiation-treated groups using a Wilcoxon rank-sum test.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Significantly higher T₂ values were found in the cortex and outer stripe of the outer medulla in all treated animals compared with the control group (<i>p</i> &lt; 0.05). In addition, these changes in T₂ were observed before any changes in serum parameters, animal body weight, and kidney volume occurred.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>T₂ mapping is sensitive to radiation-induced tubulointerstitial changes in the kidney.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"94 1","pages":"251-261"},"PeriodicalIF":3.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143024031","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":"Generalizable, sequence-invariant deep learning image reconstruction for subspace-constrained quantitative MRI","authors":"Zheyuan Hu,&nbsp;Zihao Chen,&nbsp;Tianle Cao,&nbsp;Hsu-Lei Lee,&nbsp;Yibin Xie,&nbsp;Debiao Li,&nbsp;Anthony G. Christodoulou","doi":"10.1002/mrm.30433","DOIUrl":"10.1002/mrm.30433","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Purpose&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;To develop a deep subspace learning network that can function across different pulse sequences.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Methods&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;A contrast-invariant component-by-component (CBC) network structure was developed and compared against previously reported spatiotemporal multicomponent (MC) structure for reconstructing MR Multitasking images. A total of 130, 167, and 16 subjects were imaged using T&lt;sub&gt;1&lt;/sub&gt;, T&lt;sub&gt;1&lt;/sub&gt;-T&lt;sub&gt;2&lt;/sub&gt;, and T&lt;sub&gt;1&lt;/sub&gt;-T&lt;sub&gt;2&lt;/sub&gt;- &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;T&lt;/mi&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;mo&gt;*&lt;/mo&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{T}}_2^{ast } $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;-fat fraction (FF) mapping sequences, respectively. We compared CBC and MC networks in matched-sequence experiments (same sequence for training and testing), then examined their cross-sequence performance and generalizability by unmatched-sequence experiments (different sequences for training and testing). A “universal” CBC network was also evaluated using mixed-sequence training (combining data from all three sequences). Evaluation metrics included image normalized root mean squared error and Bland–Altman analyses of end-diastolic maps, both versus iteratively reconstructed references.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Results&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;The proposed CBC showed significantly better normalized root mean squared error than MC in both matched-sequence and unmatched-sequence experiments (&lt;i&gt;p&lt;/i&gt; &lt; 0.001), fewer structural details in quantitative error maps, and tighter limits of agreement. CBC was more generalizable than MC (smaller performance loss; &lt;i&gt;p&lt;/i&gt; = 0.006 in T&lt;sub&gt;1&lt;/sub&gt; and &lt;i&gt;p&lt;/i&gt; &lt; 0.001 in T&lt;sub&gt;1&lt;/sub&gt;-T&lt;sub&gt;2&lt;/sub&gt; from matched-sequence testing to unmatched-sequence testing) and additionally allowed training of a single universal network to reconstruct images from any of the three pulse sequences. The mixed-sequence CBC network performed similarly to matched-sequence CBC in T&lt;sub&gt;1&lt;/sub&gt; (&lt;i&gt;p&lt;/i&gt; = 0.178) and T&lt;sub&gt;1&lt;/sub&gt;-T&lt;sub&gt;2&lt;/sub&gt; (&lt;i&gt;p&lt;/i&gt; = 0121), where training data were plentiful, and performed better in T&lt;sub&gt;1&lt;/sub&gt;-T&lt;sub&gt;2&lt;/sub&gt;-&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;T&lt;/mi&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;mo&gt;*&lt;/mo&gt;\u0000 ","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"94 1","pages":"89-104"},"PeriodicalIF":3.0,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mrm.30433","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007906","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":"CESTsimu: An open-source GUI for spectral and spatial CEST simulation","authors":"Huabin Zhang,&nbsp;Bensheng Qiu,&nbsp;Jiadi Xu,&nbsp;Kannie WY Chan,&nbsp;Jianpan Huang","doi":"10.1002/mrm.30430","DOIUrl":"10.1002/mrm.30430","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Purpose&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;The aim of this study was to create a user-friendly CEST simulation tool with a GUI for both spectral (1D Z-spectra) and spatial (2D phantom) CEST experiments, making the CEST simulation easier to perform.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Methods&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;CESTsimu was developed using MATLAB App Designer. It consists of three modules: Saturation Settings, Exchange Settings, and Phantom Settings. CESTsimu can not only import/export files in the defined format but can also import files generated by other existing simulation platforms (e.g. pulseq-CEST).&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Results&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;The 1D Z-spectrum simulation results demonstrated the effectiveness of CESTsimu in simulating Z-spectra under various saturation (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;0&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{B}}_0 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{B}}_1 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) and exchange settings (concentration and exchange rate). The 2D simulation results showed that CESTsimu can generate an arbitrary number of phantoms with different shapes under different noise conditions. Notably, CESTsimu could also simulate &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;0&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{B}}_0 $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 ","PeriodicalId":18065,"journal":{"name":"Magnetic Resonance in Medicine","volume":"93 6","pages":"2595-2609"},"PeriodicalIF":3.0,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mrm.30430","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007895","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}