Pub Date : 2025-10-31DOI: 10.1016/j.mri.2025.110551
Guijiao Zhao , Chen Zhou , Jianxing Liu , Yue Hu , Peng Li
Accelerated magnetic resonance imaging (MRI) reconstruction from undersampled -space data is a challenging inverse problem that has attracted significant attention in the MRI community. Diffusion models have recently emerged as a promising solution for MRI reconstruction, as they can generate high-quality samples while maintaining sample diversity. However, the inference process of diffusion models is computationally expensive, requiring thousands of steps to ensure the quality of the generated samples, which can take tens of minutes to complete. To address this issue, we propose a novel fast diffusion model for MRI reconstruction, termed FDMR, which aims to accelerate the inference process and improve reconstruction quality. The FDMR framework consists of two main components: the adversarial training of the denoising diffusion GAN and the three-stage inference framework. The adversarial training process is used to train the denoising diffusion GAN with large steps, learning an unconditional diffusion prior and embedding a deep generative prior. The proposed three-stage inference framework includes fast diffusion generation, early stopped deep generative prior adaptation, and diffusion refinement, aiming to accelerate the inference process and improve the reconstruction quality. Extensive experiments demonstrate that FDMR can achieve superior reconstruction accuracy compared to state-of-the-art diffusion methods, yet it operates 4-10 times faster, enabling the reconstruction within just 8 s.
{"title":"Fast unconditional diffusion model for accelerated MRI reconstruction","authors":"Guijiao Zhao , Chen Zhou , Jianxing Liu , Yue Hu , Peng Li","doi":"10.1016/j.mri.2025.110551","DOIUrl":"10.1016/j.mri.2025.110551","url":null,"abstract":"<div><div>Accelerated magnetic resonance imaging (MRI) reconstruction from undersampled <span><math><mi>k</mi></math></span>-space data is a challenging inverse problem that has attracted significant attention in the MRI community. Diffusion models have recently emerged as a promising solution for MRI reconstruction, as they can generate high-quality samples while maintaining sample diversity. However, the inference process of diffusion models is computationally expensive, requiring thousands of steps to ensure the quality of the generated samples, which can take tens of minutes to complete. To address this issue, we propose a novel fast diffusion model for MRI reconstruction, termed FDMR, which aims to accelerate the inference process and improve reconstruction quality. The FDMR framework consists of two main components: the adversarial training of the denoising diffusion GAN and the three-stage inference framework. The adversarial training process is used to train the denoising diffusion GAN with large steps, learning an unconditional diffusion prior and embedding a deep generative prior. The proposed three-stage inference framework includes fast diffusion generation, early stopped deep generative prior adaptation, and diffusion refinement, aiming to accelerate the inference process and improve the reconstruction quality. Extensive experiments demonstrate that FDMR can achieve superior reconstruction accuracy compared to state-of-the-art diffusion methods, yet it operates 4-10 times faster, enabling the reconstruction within just 8 s.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110551"},"PeriodicalIF":2.0,"publicationDate":"2025-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145431523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-30DOI: 10.1016/j.mri.2025.110554
Steven Winata , Daniel Christopher Hoinkiss , Graeme Alexander Keith , Salim al-Wasity , David Andrew Porter
Magnetic resonance imaging (MRI) at ultra-high field strengths such as 7 T unlocks new opportunities. Functional MRI (fMRI) is especially able to benefit due to the increase in the inherent blood‑oxygen-level-dependant (BOLD) signal. In order to utilise this, the higher motion sensitivity at 7 T and various motion sources in fMRI protocols, especially task-based ones, need to be mitigated. This motivated the development of a 7 T implementation of the real-time, prospective Multislice Prospective Acquisition Correction (MS-PACE) technique. MS-PACE allows for a sub-TR, higher temporal resolution motion correction without the need for external tracking equipment. We present an echo-planar imaging (EPI) implementation, evaluated in a 7 T task-based fMRI study. The results show that the technique led to significant, consistent reduction in residual motion across the scanned cohort. An analysis of the temporal SNR of the resting-state scans indicated a general increase in this metric when prospective motion correction was activated. Functional analysis of the data showed an apparent reduction of artefactual activations compared to a standard retrospective motion correction algorithm.
{"title":"Real-time multislice-to-volume motion correction for task-based EPI-fMRI at 7 T","authors":"Steven Winata , Daniel Christopher Hoinkiss , Graeme Alexander Keith , Salim al-Wasity , David Andrew Porter","doi":"10.1016/j.mri.2025.110554","DOIUrl":"10.1016/j.mri.2025.110554","url":null,"abstract":"<div><div>Magnetic resonance imaging (MRI) at ultra-high field strengths such as 7 T unlocks new opportunities. Functional MRI (fMRI) is especially able to benefit due to the increase in the inherent blood‑oxygen-level-dependant (BOLD) signal. In order to utilise this, the higher motion sensitivity at 7 T and various motion sources in fMRI protocols, especially task-based ones, need to be mitigated. This motivated the development of a 7 T implementation of the real-time, prospective Multislice Prospective Acquisition Correction (MS-PACE) technique. MS-PACE allows for a sub-TR, higher temporal resolution motion correction without the need for external tracking equipment. We present an echo-planar imaging (EPI) implementation, evaluated in a 7 T task-based fMRI study. The results show that the technique led to significant, consistent reduction in residual motion across the scanned cohort. An analysis of the temporal SNR of the resting-state scans indicated a general increase in this metric when prospective motion correction was activated. Functional analysis of the data showed an apparent reduction of artefactual activations compared to a standard retrospective motion correction algorithm.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110554"},"PeriodicalIF":2.0,"publicationDate":"2025-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145422017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-30DOI: 10.1016/j.mri.2025.110542
Yuemei Cui , Ya Li , Jing Na , Junling Lu , Xinyou Wang , Shichao Han , Jun Wang
Objectives
To assess the diagnostic performance of radiomics, habitat imaging, and 2.5D deep learning models for MRI-based prediction of parametrial invasion in cervical cancer, and to evaluate the clinical utility of a multimodal integrated model.
Methods
This dual-center retrospective study included 290 patients with FIGO stage IB1–IIB cervical cancer who underwent preoperative MRI. Patients from Center A (n = 227) were divided into training and validation cohorts, while patients from Center B (n = 63) comprised the external test cohort. Radiomic features were extracted, habitat imaging was performed using k-means clustering, and a 2.5D deep learning model incorporated adjacent slices. Feature selection was conducted using Pearson correlation and LASSO regression. Machine learning models were developed, and an integrated model was constructed. Model performance was evaluated using AUC and accuracy. AUCs were compared with DeLong tests, calibration was assessed with the Hosmer–Lemeshow test, and clinical utility was evaluated with decision curve analysis.
Results
The integrated model outperformed all individual models, achieving AUCs of 0.973, 0.901, and 0.906 in the training, validation, and external test cohorts, respectively. Among individual models, the deep-learning model showed the highest AUCs (0.954, 0.803, 0.833), followed by habitat imaging (0.860, 0.811, 0.843). In the external test cohort, the peritumoral radiomics model outperformed the intratumoral model (0.843 vs. 0.719). The clinical model showed the lowest performance. Hosmer–Lemeshow tests indicated good calibration, and decision curve analysis confirmed superior clinical utility of the integrated model.
Conclusion
The multimodal integrated model, combining radiomics, habitat imaging, 2.5D deep learning, and clinical features, demonstrated superior predictive performance for parametrial invasion in cervical cancer compared with individual models. This approach may enhance preoperative assessment, guide clinical decision-making, and optimize treatment strategies.
{"title":"Integration of radiomics, habitat imaging, and deep learning for MRI-based prediction of parametrial invasion in cervical cancer: A dual-center study","authors":"Yuemei Cui , Ya Li , Jing Na , Junling Lu , Xinyou Wang , Shichao Han , Jun Wang","doi":"10.1016/j.mri.2025.110542","DOIUrl":"10.1016/j.mri.2025.110542","url":null,"abstract":"<div><h3>Objectives</h3><div>To assess the diagnostic performance of radiomics, habitat imaging, and 2.5D deep learning models for MRI-based prediction of parametrial invasion in cervical cancer, and to evaluate the clinical utility of a multimodal integrated model.</div></div><div><h3>Methods</h3><div>This dual-center retrospective study included 290 patients with FIGO stage IB1–IIB cervical cancer who underwent preoperative MRI. Patients from Center A (<em>n</em> = 227) were divided into training and validation cohorts, while patients from Center B (<em>n</em> = 63) comprised the external test cohort. Radiomic features were extracted, habitat imaging was performed using k-means clustering, and a 2.5D deep learning model incorporated adjacent slices. Feature selection was conducted using Pearson correlation and LASSO regression. Machine learning models were developed, and an integrated model was constructed. Model performance was evaluated using AUC and accuracy. AUCs were compared with DeLong tests, calibration was assessed with the Hosmer–Lemeshow test, and clinical utility was evaluated with decision curve analysis.</div></div><div><h3>Results</h3><div>The integrated model outperformed all individual models, achieving AUCs of 0.973, 0.901, and 0.906 in the training, validation, and external test cohorts, respectively. Among individual models, the deep-learning model showed the highest AUCs (0.954, 0.803, 0.833), followed by habitat imaging (0.860, 0.811, 0.843). In the external test cohort, the peritumoral radiomics model outperformed the intratumoral model (0.843 vs. 0.719). The clinical model showed the lowest performance. Hosmer–Lemeshow tests indicated good calibration, and decision curve analysis confirmed superior clinical utility of the integrated model.</div></div><div><h3>Conclusion</h3><div>The multimodal integrated model, combining radiomics, habitat imaging, 2.5D deep learning, and clinical features, demonstrated superior predictive performance for parametrial invasion in cervical cancer compared with individual models. This approach may enhance preoperative assessment, guide clinical decision-making, and optimize treatment strategies.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110542"},"PeriodicalIF":2.0,"publicationDate":"2025-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145422019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-26DOI: 10.1016/j.mri.2025.110555
Constantin von Deuster , Georg Wilhelm Kajdi , Shila Pazahr , Nikolai Pfender , Markus Hupp , Armin Curt , Reto Sutter , Daniel Nanz
Background
The aim of this study was to investigate the feasibility of MR-tagging for direct visualization and quantification of pathologically altered spinal-cord motion in patients with cervical spinal stenosis and compare it to the standard approach of phase contrast (PC) imaging.
Methods
In this prospective study, sagittal sections (22 cm field of view) of the cervical spine of nine patients with mono-segmental spinal-canal stenosis were imaged in different heart phases after selective pre-saturation of tissue magnetization in an axially oriented tag-stripe pattern (MR-tagging). Video loops of images acquired in different heart phases were viewed to directly observe and compare head-feet (HF) displacement at the level of the stenosis. The maximum HF displacement of MR-tags in the cord was quantitatively assessed and compared to that derived from integration of PC velocity data.
Results
Regional MR-tag displacement in the spinal cord could successfully be observed in all patients (4 females, 5 males, mean age 57 ± 7 years). Maximum displacement data derived from tagging at the stenosis level correlated excellently (R2 = 0.84) with matched measurements from PC imaging.
Conclusion
Without complex post-processing, MR-tag imaging provides an intuitive direct visualization and quantification of pathologically altered spinal-cord motion at the level of cervical stenosis offering a faster alternative to PC imaging in clinical routine.
{"title":"Feasibility of MR-tagging to quantify spinal cord motion in degenerative cervical myelopathy","authors":"Constantin von Deuster , Georg Wilhelm Kajdi , Shila Pazahr , Nikolai Pfender , Markus Hupp , Armin Curt , Reto Sutter , Daniel Nanz","doi":"10.1016/j.mri.2025.110555","DOIUrl":"10.1016/j.mri.2025.110555","url":null,"abstract":"<div><h3>Background</h3><div>The aim of this study was to investigate the feasibility of MR-tagging for direct visualization and quantification of pathologically altered spinal-cord motion in patients with cervical spinal stenosis and compare it to the standard approach of phase contrast (PC) imaging.</div></div><div><h3>Methods</h3><div>In this prospective study, sagittal sections (22 cm field of view) of the cervical spine of nine patients with mono-segmental spinal-canal stenosis were imaged in different heart phases after selective pre-saturation of tissue magnetization in an axially oriented tag-stripe pattern (MR-tagging). Video loops of images acquired in different heart phases were viewed to directly observe and compare head-feet (HF) displacement at the level of the stenosis. The maximum HF displacement of MR-tags in the cord was quantitatively assessed and compared to that derived from integration of PC velocity data.</div></div><div><h3>Results</h3><div>Regional MR-tag displacement in the spinal cord could successfully be observed in all patients (4 females, 5 males, mean age 57 ± 7 years). Maximum displacement data derived from tagging at the stenosis level correlated excellently (R<sup>2</sup> = 0.84) with matched measurements from PC imaging.</div></div><div><h3>Conclusion</h3><div>Without complex post-processing, MR-tag imaging provides an intuitive direct visualization and quantification of pathologically altered spinal-cord motion at the level of cervical stenosis offering a faster alternative to PC imaging in clinical routine.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110555"},"PeriodicalIF":2.0,"publicationDate":"2025-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145390825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-24DOI: 10.1016/j.mri.2025.110550
Radim Kořínek, Lucie Krátká, Zenon Starčuk Jr
Purpose
Quantifying proton density fat fraction (PDFF) in small abdominal organs is challenging due to low T1/T2 contrast and susceptibility artifacts. We develop a hybrid 7-echo CSE-MRI sequence with arbitrary echo spacing, inspired by GRASE-type imaging, aiming for distortion-free PDFF mapping in small animals. The method is designed to be comparable to established conventional methods, with potential for increased robustness.
Methods
We developed a Fast Spin Echo Asymmetric Bipolar Multi-Gradient Echo (FSE-AbMGE) sequence by integrating a fast spin-echo readout with an asymmetrically placed bipolar multi-echo gradient-echo train. The sequence was implemented at 9.4 T and combined with robust phase unwrapping and water-fat reconstruction algorithms using full fat spectral modeling. Validation was performed using phantoms with known PDFF values (0–22 %) and in vivo experiments on several female mice (n = 2). Reference PDFF values were obtained using single-voxel 1H-MRS.
Results
The proposed method enabled high-resolution PDFF mapping with minimal chemical shift and susceptibility artifacts. Phantom experiments showed strong agreement with both spectroscopic and ground truth values (R2 > 0.98, p < 0.001). The method was also tested in vivo, demonstrating robust water-fat separation and quantification.
Conclusion
The FSE-AbMGE sequence is well-suited for accurate abdominal fat quantification in small animals. While additional validation is needed, especially in reproducibility and broader biological settings, the method shows promise for high-field fat quantification and may offer a framework adaptable to lower-field pre-clinical applications.
{"title":"Quantitative proton density fat-fraction at 9.4 T using fast spin echo and asymmetric multi-echo gradient-echo pulse sequences","authors":"Radim Kořínek, Lucie Krátká, Zenon Starčuk Jr","doi":"10.1016/j.mri.2025.110550","DOIUrl":"10.1016/j.mri.2025.110550","url":null,"abstract":"<div><h3><strong>Purpose</strong></h3><div>Quantifying proton density fat fraction (PDFF) in small abdominal organs is challenging due to low <em>T</em><sub>1</sub>/<em>T</em><sub>2</sub> contrast and susceptibility artifacts. We develop a hybrid 7-echo CSE-MRI sequence with arbitrary echo spacing, inspired by GRASE-type imaging, aiming for distortion-free PDFF mapping in small animals. The method is designed to be comparable to established conventional methods, with potential for increased robustness.</div></div><div><h3><strong>Methods</strong></h3><div>We developed a Fast Spin Echo Asymmetric Bipolar Multi-Gradient Echo (FSE-AbMGE) sequence by integrating a fast spin-echo readout with an asymmetrically placed bipolar multi-echo gradient-echo train. The sequence was implemented at 9.4 T and combined with robust phase unwrapping and water-fat reconstruction algorithms using full fat spectral modeling. Validation was performed using phantoms with known PDFF values (0–22 %) and in vivo experiments on several female mice (<em>n</em> = 2). Reference PDFF values were obtained using single-voxel <sup>1</sup>H-MRS.</div></div><div><h3><strong>Results</strong></h3><div>The proposed method enabled high-resolution PDFF mapping with minimal chemical shift and susceptibility artifacts. Phantom experiments showed strong agreement with both spectroscopic and ground truth values (R<sup>2</sup> > 0.98, <em>p</em> < 0.001). The method was also tested in vivo, demonstrating robust water-fat separation and quantification.</div></div><div><h3><strong>Conclusion</strong></h3><div>The FSE-AbMGE sequence is well-suited for accurate abdominal fat quantification in small animals. While additional validation is needed, especially in reproducibility and broader biological settings, the method shows promise for high-field fat quantification and may offer a framework adaptable to lower-field pre-clinical applications.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110550"},"PeriodicalIF":2.0,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-24DOI: 10.1016/j.mri.2025.110552
Jie Huang
It is imperative to study individual brain functioning for understanding the neural bases of individual behavioral and clinical traits. BOLD-fMRI measures the four-dimensional (3 spatial and 1 temporal) neural activity across the entire brain at large-scale systems level. All local activities across the entire brain constitute the whole brain activity and each local activity is a part of that whole brain activity. Unlike a local activity that is characterized by its temporal neural activity, the whole brain activity is characterized by its spatial variation across the entire brain. We present a novel data-driven method to analyze the whole brain activity when performing tasks. The method enabled us to analyze the whole brain activity for each task trial and each individual subject with no requirement of a priori knowledge of task-evoked BOLD response. Our study revealed a quantitative spatiotemporal relationship of the whole brain activity with the local activities. The whole brain activity demonstrated a remarkable dynamic activity that varied from trial to trial when performing the same task repeatedly, showing the importance of analyzing the whole brain activity for investigating the neural bases of personal traits.
{"title":"The quantitative spatiotemporal relationship of whole brain activity of human brains revealed by fMRI","authors":"Jie Huang","doi":"10.1016/j.mri.2025.110552","DOIUrl":"10.1016/j.mri.2025.110552","url":null,"abstract":"<div><div>It is imperative to study individual brain functioning for understanding the neural bases of individual behavioral and clinical traits. BOLD-fMRI measures the four-dimensional (3 spatial and 1 temporal) neural activity across the entire brain at large-scale systems level. All local activities across the entire brain constitute the whole brain activity and each local activity is a part of that whole brain activity. Unlike a local activity that is characterized by its temporal neural activity, the whole brain activity is characterized by its spatial variation across the entire brain. We present a novel data-driven method to analyze the whole brain activity when performing tasks. The method enabled us to analyze the whole brain activity for each task trial and each individual subject with no requirement of a priori knowledge of task-evoked BOLD response. Our study revealed a quantitative spatiotemporal relationship of the whole brain activity with the local activities. The whole brain activity demonstrated a remarkable dynamic activity that varied from trial to trial when performing the same task repeatedly, showing the importance of analyzing the whole brain activity for investigating the neural bases of personal traits.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110552"},"PeriodicalIF":2.0,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-24DOI: 10.1016/j.mri.2025.110553
Lauritz Klünder , Bastian Maus , María Belén Rivas Aiello , Athina Drakonaki , Michael Holtkamp , Uwe Karst , Christos Gatsogiannis , Cristian Strassert , Cornelius Faber
Superparamagnetic iron oxide nanoparticles are used in MRI as or contrast agents and, in combination with relaxometry, enable quantitative analysis of physiological and pathological processes. However, the induced changes in relaxation times are influenced by a complex interplay of the contrast agents' physicochemical properties. Here, an open-source Monte Carlo simulation pipeline was implemented, which enables the characterization of these relaxation time changes caused by MRI contrast agents. The simulation tool was validated by showing that simulated relaxation times for iron oxide particles matched the solutions of analytical models of the respective diffusion regimes. For comparison with relaxometry measurements, and of four MRI contrast agents Ferucarbotran, FeraSpin XL, magnetite nanohexagons (MNH@OH) and magnetite nanocubes (MNC@OH) were simulated, using three approaches for modeling contrast agent size and composition: 1) uniform particle sizes using the median hydrodynamic radii; 2) distributed radii corresponding to measured hydrodynamic radius distributions; 3) size-distributed magnetite cores in a coating layer of uniform radius. The simulation accurately reproduced measured relaxation times when appropriate modeling strategies for contrast agent size and composition were used. For FeraSpin XL and MNH@OH, using uniform radii provided good estimates of relaxation times, which was further improved by using the size distributions. For MNC@OH, discrepancies in simulated and measured for all approaches were attributed to particle aggregation. For Ferucarbotran, coating and size distribution of the core had to be considered to match experimental data.
{"title":"Monte Carlo simulations of transverse relaxation for characterization of physicochemical properties of superparamagnetic iron oxide nanoparticles","authors":"Lauritz Klünder , Bastian Maus , María Belén Rivas Aiello , Athina Drakonaki , Michael Holtkamp , Uwe Karst , Christos Gatsogiannis , Cristian Strassert , Cornelius Faber","doi":"10.1016/j.mri.2025.110553","DOIUrl":"10.1016/j.mri.2025.110553","url":null,"abstract":"<div><div>Superparamagnetic iron oxide nanoparticles are used in MRI as <span><math><msub><mi>T</mi><mn>2</mn></msub></math></span> or <span><math><msubsup><mi>T</mi><mn>2</mn><mo>∗</mo></msubsup></math></span> contrast agents and, in combination with relaxometry, enable quantitative analysis of physiological and pathological processes. However, the induced changes in relaxation times are influenced by a complex interplay of the contrast agents' physicochemical properties. Here, an open-source Monte Carlo simulation pipeline was implemented, which enables the characterization of these relaxation time changes caused by MRI contrast agents. The simulation tool was validated by showing that simulated relaxation times for iron oxide particles matched the solutions of analytical models of the respective diffusion regimes. For comparison with relaxometry measurements, <span><math><msub><mi>T</mi><mn>2</mn></msub></math></span> and <span><math><msubsup><mi>T</mi><mn>2</mn><mo>∗</mo></msubsup></math></span> of four MRI contrast agents Ferucarbotran, FeraSpin XL, magnetite nanohexagons (MNH@OH) and magnetite nanocubes (MNC@OH) were simulated, using three approaches for modeling contrast agent size and composition: 1) uniform particle sizes using the median hydrodynamic radii; 2) distributed radii corresponding to measured hydrodynamic radius distributions; 3) size-distributed magnetite cores in a coating layer of uniform radius. The simulation accurately reproduced measured relaxation times when appropriate modeling strategies for contrast agent size and composition were used. For FeraSpin XL and MNH@OH, using uniform radii provided good estimates of relaxation times, which was further improved by using the size distributions. For MNC@OH, discrepancies in simulated and measured <span><math><msub><mi>T</mi><mn>2</mn></msub></math></span> for all approaches were attributed to particle aggregation. For Ferucarbotran, coating and size distribution of the core had to be considered to match experimental data.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110553"},"PeriodicalIF":2.0,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-17DOI: 10.1016/j.mri.2025.110541
Zalán Petneházy , Dávid Bognár , Péter Laar , Tamás Dóczi , Attila Schwarcz , Bálint S. Környei , Arnold Tóth
Objectives
This study aimed to determine whether focal MRI lesions such as microbleeds (MBs) and focal white matter hyperintensities (FWMHs) serve as reliable and specific markers for tract-level white matter injury in traumatic brain injury (TBI).
Materials & methods
Twenty-two patients with moderate-to-severe TBI and 22 age-matched healthy controls underwent MRI on a 3 T Siemens Prisma scanner. Imaging included susceptibility-weighted imaging (SWI), fluid-attenuated inversion recovery (FLAIR), and diffusion tensor imaging (DTI). Focal lesions were manually identified on SWI and FLAIR and mapped onto tractography reconstructions. Diffusion metrics—fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were compared between lesion-affected tracts, contralateral normal-appearing white matter (NAWM), and corresponding control tracts. Statistical analyses were performed using repeated measures ANOVA with Greenhouse-Geisser correction and Bonferroni-adjusted post hoc tests for FA. Friedman tests were conducted for MD, AD, and RD, followed by Bonferroni-corrected Wilcoxon post hoc comparisons.
Results
In this study, we identified 27 MBs and 66 FWMHs intersecting white matter tracts. We observed notable differences in diffusion metrics when comparing lesion-affected tracts to healthy controls. In MB-affected tracts, fractional anisotropy (FA) differed significantly (p = 0.002), while mean diffusivity (MD) also showed a significant alteration (p = 0.002), along with radial diffusivity (RD) (p < 0.001). Similarly, in FWMH-affected tracts, significant differences were observed in FA (p < 0.001), MD (p < 0.001), axial diffusivity (AD) (p < 0.001), and RD (p < 0.001). However, we did not find any significant differences between lesion-affected tracts and the contralateral normal-appearing white matter (NAWM).
Conclusion
MBs and FWMHs do not co-localize with axonal injury at the tract level but indicate a global white matter damage.
{"title":"Investigating microbleeds and white matter hyperintensities in TBI at a tract-level: A DTI study","authors":"Zalán Petneházy , Dávid Bognár , Péter Laar , Tamás Dóczi , Attila Schwarcz , Bálint S. Környei , Arnold Tóth","doi":"10.1016/j.mri.2025.110541","DOIUrl":"10.1016/j.mri.2025.110541","url":null,"abstract":"<div><h3>Objectives</h3><div>This study aimed to determine whether focal MRI lesions such as microbleeds (MBs) and focal white matter hyperintensities (FWMHs) serve as reliable and specific markers for tract-level white matter injury in traumatic brain injury (TBI).</div></div><div><h3>Materials & methods</h3><div>Twenty-two patients with moderate-to-severe TBI and 22 age-matched healthy controls underwent MRI on a 3 T Siemens Prisma scanner. Imaging included susceptibility-weighted imaging (SWI), fluid-attenuated inversion recovery (FLAIR), and diffusion tensor imaging (DTI). Focal lesions were manually identified on SWI and FLAIR and mapped onto tractography reconstructions. Diffusion metrics—fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were compared between lesion-affected tracts, contralateral normal-appearing white matter (NAWM), and corresponding control tracts. Statistical analyses were performed using repeated measures ANOVA with Greenhouse-Geisser correction and Bonferroni-adjusted post hoc tests for FA. Friedman tests were conducted for MD, AD, and RD, followed by Bonferroni-corrected Wilcoxon post hoc comparisons.</div></div><div><h3>Results</h3><div>In this study, we identified 27 MBs and 66 FWMHs intersecting white matter tracts. We observed notable differences in diffusion metrics when comparing lesion-affected tracts to healthy controls. In MB-affected tracts, fractional anisotropy (FA) differed significantly (<em>p</em> = 0.002), while mean diffusivity (MD) also showed a significant alteration (p = 0.002), along with radial diffusivity (RD) (<em>p</em> < 0.001). Similarly, in FWMH-affected tracts, significant differences were observed in FA (<em>p</em> < 0.001), MD (p < 0.001), axial diffusivity (AD) (p < 0.001), and RD (p < 0.001). However, we did not find any significant differences between lesion-affected tracts and the contralateral normal-appearing white matter (NAWM).</div></div><div><h3>Conclusion</h3><div>MBs and FWMHs do not co-localize with axonal injury at the tract level but indicate a global white matter damage.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110541"},"PeriodicalIF":2.0,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145329540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-14DOI: 10.1016/j.mri.2025.110536
Junde Zhou , Qin Wang , Yanting Liu , Lu Zhang , Jiao Li , Shuo Li , Dong Liu , Jinxia Zhu , Robert Grimm , Alto Stemmer , Shuang Xia , Wenyang Huang , Sheng Xie , Haibo Zhang , Jian Li , Huadan Xue , Zhengyu Jin
Purpose
This study aimed to explore the utility of total tumor apparent diffusion coefficient (ttADC) histogram analysis based on whole-body diffusion-weighted magnetic resonance imaging (DWI-MRI) for prognostic stratification in patients with Revised International Staging System stage II (R-ISS II) multiple myeloma (MM).
Methods
Patients with R-ISS II MM who underwent baseline whole-body MRI prior to treatment were retrospectively enrolled. The ttADC histogram parameters of the whole-body DWI-MRI were obtained using MR Total Tumor Load software (Siemens Healthcare, Erlangen, Germany). The overall survival (OS) and the progression-free survival (PFS) of the cohort was recorded. Cox regression analyses were used to evaluate the clinical features and ttADC histogram parameters for their association with OS and PFS.
Results
A total of 61 R-ISS II MM patients were retrospectively included. During a mean follow-up period of 80 months, 27 patients died, 4 patients lost follow-up for OS, and 4 patients lost follow-up for PFS. Multivariate analysis revealed that increased median ttADC (≥0.620 × 10−3 mm2/s) [hazard ratio (HR) = 2.291, P = 0.046, 95 % confidence interval (CI): 1.014–5.175] was independently associated with OS in R-ISS II MM patients. No significant association was observed between the ttADC histogram parameters and PFS.
Conclusion
The median ttADC of whole-body DWI-MRI is an independent predictor of OS in R-ISS II MM patients, suggesting its potential role in further prognostic stratification in this patients' subgroup.
{"title":"Total tumor apparent diffusion coefficient histogram analysis of whole-body DWI-MRI for prognostic stratification in patients with R-ISS stage II multiple myeloma","authors":"Junde Zhou , Qin Wang , Yanting Liu , Lu Zhang , Jiao Li , Shuo Li , Dong Liu , Jinxia Zhu , Robert Grimm , Alto Stemmer , Shuang Xia , Wenyang Huang , Sheng Xie , Haibo Zhang , Jian Li , Huadan Xue , Zhengyu Jin","doi":"10.1016/j.mri.2025.110536","DOIUrl":"10.1016/j.mri.2025.110536","url":null,"abstract":"<div><h3>Purpose</h3><div>This study aimed to explore the utility of total tumor apparent diffusion coefficient (ttADC) histogram analysis based on whole-body diffusion-weighted magnetic resonance imaging (DWI-MRI) for prognostic stratification in patients with Revised International Staging System stage II (R-ISS II) multiple myeloma (MM).</div></div><div><h3>Methods</h3><div>Patients with R-ISS II MM who underwent baseline whole-body MRI prior to treatment were retrospectively enrolled. The ttADC histogram parameters of the whole-body DWI-MRI were obtained using MR Total Tumor Load software (Siemens Healthcare, Erlangen, Germany). The overall survival (OS) and the progression-free survival (PFS) of the cohort was recorded. Cox regression analyses were used to evaluate the clinical features and ttADC histogram parameters for their association with OS and PFS.</div></div><div><h3>Results</h3><div>A total of 61 R-ISS II MM patients were retrospectively included. During a mean follow-up period of 80 months, 27 patients died, 4 patients lost follow-up for OS, and 4 patients lost follow-up for PFS. Multivariate analysis revealed that increased median ttADC (≥0.620 × 10<sup>−3</sup> mm<sup>2</sup>/s) [hazard ratio (HR) = 2.291, <em>P</em> = 0.046, 95 % confidence interval (CI): 1.014–5.175] was independently associated with OS in R-ISS II MM patients. No significant association was observed between the ttADC histogram parameters and PFS.</div></div><div><h3>Conclusion</h3><div>The median ttADC of whole-body DWI-MRI is an independent predictor of OS in R-ISS II MM patients, suggesting its potential role in further prognostic stratification in this patients' subgroup.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"125 ","pages":"Article 110536"},"PeriodicalIF":2.0,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145308715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-10DOI: 10.1016/j.mri.2025.110534
Ruchuan Chen , Guoqing Hu , Bingni Zhou , Hualei Gan , Xiaofeng Liu , Lin Deng , Liangping Zhou , Yajia Gu , Xiaohang Liu
Purpose
To develop Homologous Recombination Repair (HRR) Genes mutations prediction models for prostate cancer using MRI radiomics and clinicopathological features.
Methods
Totally 353 prostate cancer patients (102 with HRR genes mutations) from three centers (center 1: training and internal test cohorts, center 2 and 3: external test cohorts) underwent multiparametric MRI. Each patient's index tumor lesion was delineated on T2-weighted imaging (T2WI), dynamic contrast enhancement (DCE) MRI, diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) images to obtain 428 radiomics features. Features associated with mutations were selected from clinicopathological features using Mann-Whitney U and Logistic regression (LR) test, radiomics features using Least Absolute Shrinkage and Selection Operator. Clinicopathological model was constructed with selected clinicopathological features. Logistic regression (LR), support vector machine (SVM) and linear discriminant analysis (LDA) classifiers were used to construct Radiomics and combined clinicopathological-radiomics models. Predictive efficiencies of models were compared using areas under the receiver operating characteristic curve (AUC).
Results
One clinicopathological and six radiomics features were selected. Radiomics with SVM, LR, LDA and Clinicopathological models achieved AUCs of 0.76, 0.76, 0.76, 0.68 and 0.75, 0.76, 0.67, 0.73 in internal and external test cohort. AUCs of combined clinicopathological-radiomics models with LDA in internal and external test cohort (0.83 and 0.82) were slightly higher than combined models with LR (0.81 and 0.79) and SVM (both 0.80) (P > 0.05), but were significantly higher than radiomics and clinicopathological models in both cohorts (P < 0.05).
Conclusion
LDA classifier incorporating radiomics and clinicopathological features predicting could effectively predict HRR genes mutations in prostate cancer.
{"title":"Combination of clinicopathological and MRI based radiomics features in predicting homologous recombination repair genes mutations in prostate cancer","authors":"Ruchuan Chen , Guoqing Hu , Bingni Zhou , Hualei Gan , Xiaofeng Liu , Lin Deng , Liangping Zhou , Yajia Gu , Xiaohang Liu","doi":"10.1016/j.mri.2025.110534","DOIUrl":"10.1016/j.mri.2025.110534","url":null,"abstract":"<div><h3>Purpose</h3><div>To develop Homologous Recombination Repair (HRR) Genes mutations prediction models for prostate cancer using MRI radiomics and clinicopathological features.</div></div><div><h3>Methods</h3><div>Totally 353 prostate cancer patients (102 with HRR genes mutations) from three centers (center 1: training and internal test cohorts, center 2 and 3: external test cohorts) underwent multiparametric MRI. Each patient's index tumor lesion was delineated on T2-weighted imaging (T2WI), dynamic contrast enhancement (DCE) MRI, diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) images to obtain 428 radiomics features. Features associated with mutations were selected from clinicopathological features using Mann-Whitney U and Logistic regression (LR) test, radiomics features using Least Absolute Shrinkage and Selection Operator. Clinicopathological model was constructed with selected clinicopathological features. Logistic regression (LR), support vector machine (SVM) and linear discriminant analysis (LDA) classifiers were used to construct Radiomics and combined clinicopathological-radiomics models. Predictive efficiencies of models were compared using areas under the receiver operating characteristic curve (AUC).</div></div><div><h3>Results</h3><div>One clinicopathological and six radiomics features were selected. Radiomics with SVM, LR, LDA and Clinicopathological models achieved AUCs of 0.76, 0.76, 0.76, 0.68 and 0.75, 0.76, 0.67, 0.73 in internal and external test cohort. AUCs of combined clinicopathological-radiomics models with LDA in internal and external test cohort (0.83 and 0.82) were slightly higher than combined models with LR (0.81 and 0.79) and SVM (both 0.80) (<em>P</em> > 0.05), but were significantly higher than radiomics and clinicopathological models in both cohorts (<em>P</em> < 0.05).</div></div><div><h3>Conclusion</h3><div>LDA classifier incorporating radiomics and clinicopathological features predicting could effectively predict HRR genes mutations in prostate cancer.</div></div>","PeriodicalId":18165,"journal":{"name":"Magnetic resonance imaging","volume":"124 ","pages":"Article 110534"},"PeriodicalIF":2.0,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145275099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}