Magnetic resonance imaging最新文献_第3页

Assessment of a truncation-based R2* fitting technique for quantifying high liver iron concentration (LIC) 评估基于截断的R2*拟合技术定量高肝铁浓度（LIC）。

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-05-01 Epub Date: 2026-01-03 DOI: 10.1016/j.mri.2026.110609

Marshall S. Sussman , Bryan Buckley , Stephan A.R. Kannengiesser , Kartik S. Jhaveri

Background

R2*-based MRI liver iron concentration (LIC) quantification has several advantages. However, lower accuracies can impact utility in high iron overload states.

Purpose

To develop and characterize an R2* fitting technique based on truncation. Unlike other truncation methods, this approach maximizes the accuracy of LIC estimates at the possible cost of precision, rather than the converse. The hypothesis of this study is that the truncation-based method can provide accurate LIC estimates over the full range of LICs characterized by FerriScan.

Study type: Retrospective subjects

170 patients undergoing chelation treatment for iron overload had undergone FerriScan and R2* MRI during the same exam.

Field strength/sequence

Field strength was 1.5 T. Pulse sequences included 2D multi-slice spin-echo for FerriScan, and 3D 5-echo gradient echo for R2* mapping.

Assessment

LIC was calculated for both non- and truncated R2* fits using a previously-derived calibration curve. The resulting LIC values were compared to those from the reference FerriScan technique. Precision was also assessed for LIC estimates.

Statistical tests

LIC values were compared using a Wilcoxon signed rank test. Statistical significance was set at the 95 % confidence level.

Results

LIC estimates from truncated R2* fits were equal to FerriScan at all LIC values, while those from non-truncated fits deviated for LIC > 28 mg Fe / g dw liver. The precision of the truncated fits was better than the non-truncated fits.

Data conclusion

The truncation R2*-fitting method developed in this study permits accurate characterization of LIC over the full range of LICs characterized by FerriScan.

背景：基于R2*的MRI肝铁浓度（LIC）定量有几个优点。然而，较低的精度会影响高铁过载状态下的效用。目的：发展和表征基于截断的R2*拟合技术。与其他截断方法不同，这种方法以可能的精度代价最大化LIC估计的准确性，而不是相反。本研究的假设是，基于截断的方法可以在FerriScan表征的全范围内提供准确的LIC估计。研究类型：回顾性研究对象：170例接受铁超载螯合治疗的患者在同一检查期间进行了FerriScan和R2* MRI检查。场强/序列：场强为1.5 T。脉冲序列包括FerriScan的二维多层自旋回波和R2*映射的三维5回波梯度回波。评估：使用先前导出的校准曲线计算非R2*拟合和截断R2*拟合的LIC。将所得LIC值与参考FerriScan技术的LIC值进行比较。还评估了LIC估计值的精度。统计检验：使用Wilcoxon符号秩检验比较LIC值。统计学显著性设置为95% %置信水平。结果：截断R2*拟合的LIC估计值与FerriScan在所有LIC值上相等，而非截断拟合的LIC估计值偏离了 > 28 mg Fe / g dw肝脏。截断拟合的精度优于非截断拟合。数据结论：本研究开发的截断R2*拟合方法可以在FerriScan表征的全范围内准确表征LIC。

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引用次数: 0

DeepVBM: A fully automatic and efficient voxel-based morphometry via deep learning-based segmentation and registration methods DeepVBM：通过基于深度学习的分割和配准方法，实现全自动、高效的基于体素的形态测量。

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-05-01 Epub Date: 2026-02-02 DOI: 10.1016/j.mri.2026.110637

Pei-Mao Sun , Teng-Yi Huang , Tzu-Chao Chuang , Yi-Ru Lin , Hsiao-Wen Chung , for the Alzheimer's Disease Neuroimaging Initiative

Voxel-based morphometry (VBM) using T1-weighted magnetic resonance imaging is a pivotal tool for assessing brain structure and identifying subtle morphological changes associated with various neurological conditions. Conventional VBM workflows, however, face significant computational challenges, particularly during the nonlinear deformable registration stage, which impedes analysis of large-scale neuroimaging databases. In this study, we introduce FuseMorph, a deep learning-based registration method that refines initial zero-shot predictions from a pretrained model via iterative inference and targeted parameter search. By eliminating the need for full backpropagation and additional model retraining, FuseMorph significantly reduces computational demands, achieving registration accuracy comparable to state-of-the-art methods even in CPU-only environments. FuseMorph is integrated into DeepVBM, a fully automated VBM pipeline streamlines the processing of high-resolution MRI datasets and substantially reduces computation time compared to traditional pipelines, thereby facilitating the efficient analysis of large multi-center studies. The proposed approach was validated on multiple datasets, including an Alzheimer's disease cohort where DeepVBM successfully detected characteristic patterns of gray matter atrophy in regions such as the hippocampus, entorhinal cortex, and amygdala. These findings not only underscore the clinical relevance of the method but also demonstrate its potential for early detection and monitoring of neurodegenerative changes. This work contributes an accessible, efficient, and scalable solution for neuroimaging research, with potential applications extending to various neurodegenerative disease studies.

基于体素的形态测量（VBM）使用t1加权磁共振成像是评估大脑结构和识别与各种神经系统疾病相关的细微形态变化的关键工具。然而，传统的VBM工作流程面临着重大的计算挑战，特别是在非线性可变形配准阶段，这阻碍了大规模神经成像数据库的分析。在本研究中，我们引入了FuseMorph，这是一种基于深度学习的配准方法，通过迭代推理和目标参数搜索，从预训练模型中细化初始零射击预测。通过消除完全反向传播和额外的模型再训练的需要，FuseMorph显着降低了计算需求，即使在只有cpu的环境中，也能实现与最先进方法相当的配准精度。FuseMorph集成到DeepVBM中，一个全自动的VBM管道简化了高分辨率MRI数据集的处理，与传统管道相比，大大减少了计算时间，从而促进了大型多中心研究的高效分析。该方法在多个数据集上得到验证，包括一个阿尔茨海默病队列，其中DeepVBM成功检测到海马、内嗅皮层和杏仁核等区域灰质萎缩的特征模式。这些发现不仅强调了该方法的临床相关性，而且还证明了其在神经退行性变化的早期检测和监测方面的潜力。这项工作为神经影像学研究提供了一种方便、高效、可扩展的解决方案，并有可能应用于各种神经退行性疾病的研究。

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引用次数: 0

MR cytometry: More effective than conventional diffusion MRI in differentiating benign and malignant musculoskeletal tumors MR细胞术：在鉴别肌肉骨骼良恶性肿瘤方面比常规弥散MRI更有效。

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-04-01 Epub Date: 2025-12-24 DOI: 10.1016/j.mri.2025.110603

Zhanxing Yan , Jian Zhao , Jianling Cui , Lisha Duan , Xiaohan Feng , Xinying Zhang , Shengnan Zhang , Wenhua Liang , Xiaohui Cao , Hong Yu

Objectives

To investigate the clinical significance of microstructure imaging based on MR cytometry in the qualitative diagnosis of musculoskeletal tumors (MSTs).

Materials and methods

Participants with clinically suspected MSTs between March 2024 and March 2025 were prospectively enrolled. Conventional apparent diffusion coefficient (ADC) value and four microstructural parameters, including cell diameter (d), intracellular volume fraction (v_in), Cellularity index, and extracellular diffusivity (D_ex), were estimated using the IMPULSED method (a form of MR cytometry). The ADC_PGSE, ADC_{25 Hz} and ADC_{40 Hz} were measured at three different effective diffusion times, and the change ADC (cADC) and relative change ADC (rcADC) were measured. The performance was evaluated using the area under the receiver operating characteristic curve (AUC) and compared using the DeLong test.

Results

A total of 62 participants with benign and malignant MSTs (mean age, 47.7 ± 20.9 [SD] years; 21 women, 41men) were enrolled. Among these ADC parameters, rcADC had the highest AUC (AUC = 0.737; 95 %Cl: 0.600, 0.874; p = 0.002). Among the four microstructure parameters derived from MR cytometry, Cellularity index had the highest AUC (AUC = 0.735; 95 %Cl: 0.601, 0.868; p = 0.002). Among all parameters, the AUC of rcADC and Cellularity index is higher than that of conventional ADC (AUC = 0.728; 95 %Cl: 0.594, 0.863; p = 0.003). The combination of the four microstructure parameters of MR cytometry further improved the diagnostic performance (AUC = 0.758; 95 %Cl: 0.626, 0.890; p = 0.001).

Conclusion

MR cytometry was an effective method for helping to predict the benign and malignant MSTs and is superior to conventional ADC values.

目的：探讨基于MR细胞术的微结构成像在肌肉骨骼肿瘤（MSTs）定性诊断中的临床意义。材料和方法：前瞻性纳入2024年3月至2025年3月期间临床疑似MSTs的参与者。常规表观扩散系数（ADC）值和四个微观结构参数，包括细胞直径(d)、细胞内体积分数（vin）、细胞度指数和细胞外扩散率（Dex），使用impulse方法（一种MR细胞术）进行估计。测定三种不同有效扩散时间下ADCPGSE、ADC25 Hz和ADC40 Hz，并测定变化ADC （cADC）和相对变化ADC （rcADC）。采用受试者工作特性曲线下面积（AUC）评价其性能，并采用DeLong试验进行比较。结果：共纳入62例良恶性MSTs患者（平均年龄47.7 ± 20.9 [SD]岁，女性21例，男性41例）。在ADC参数中，rcADC的AUC最高（AUC = 0.737;95 %Cl: 0.600, 0.874; p = 0.002）。在磁共振细胞术得到的4个微观结构参数中，细胞度指数的AUC最高（AUC = 0.735;95 %Cl: 0.601, 0.868; p = 0.002）。在所有参数中，rcADC的AUC和细胞度指数均高于常规ADC （AUC = 0.728;95 %Cl: 0.594, 0.863; p = 0.003）。结合磁共振细胞术的四个显微结构参数进一步提高了诊断效能（AUC = 0.758;95 %Cl: 0.626, 0.890; p = 0.001）。结论：MR细胞术是预测MSTs良恶性的有效方法，优于传统的ADC值。

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引用次数: 0

APTWI-differential analysis for breast cancer: Association with histopathologic characteristics and early prediction of neoadjuvant chemotherapy response 乳腺癌的aptwi差异分析：与组织病理学特征和新辅助化疗反应的早期预测的关系。

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-04-01 Epub Date: 2025-12-12 DOI: 10.1016/j.mri.2025.110590

Jie Fang , Xiaoxia Wang , Lu Wang , Ying Cao , Yao Huang , Shuling Liu , Huifang Chen , Zhechuan Dai , Tao Yu , Sun Tang , Meng Lin , Yi Zhang , Jiuquan Zhang

The purpose of the study is to investigate the value of Amide proton transfer imaging(APTWI)-differential analysis in association with histopathologic characteristics, and the performance to early predict pathologic complete response (pCR) in participants with breast cancer (BC). Participants with BC who underwent pretreatment APTWI between November 2022 and April 2024 were prospectively enrolled. APT-specific signal quantification was achieved through differential analysis between model-fitted and experimentally acquired Z-spectrum at +3.5 ppm. Univariate analysis was used to identify APT^# values associated with histopathologic characteristics and pCR. The area under the receiver operating characteristic curve (AUC) analysis was performed to evaluate the diagnostic value of APTWI-DIGITAL on histopathologic characteristics and assess the predictive performance for pCR. The analysis ultimately included 123 participants with BC (mean age, 52 years±9 [SD]), 43 participants of whom received neoadjuvant chemotherapy (NAC) and 15 participants who achieved pCR. In the pre-treatment group, the APT^# values showed reasonable performance in identifying the positive status of KI67 proliferation index (P = 0.01, AUC = 0.69), and PR (P = 0.045, AUC = 0.60). In the NAC group, the APT^# values in the pCR participants showed a significant downward trend at the T1 (P = 0.01, AUC = 0.80), and was not significant between pCR and non-pCR at other timepoints. The findings suggest APTWI-differential analysis may be useful imaging biomarkers to characterize the immunohistochemical biomarkers and predict pCR to NAC in BC patients.

本研究的目的是探讨酰胺质子转移成像（APTWI）鉴别分析在乳腺癌（BC）患者中与组织病理特征相关的价值，以及早期预测病理完全缓解（pCR）的性能。在2022年11月至2024年4月期间接受APTWI预处理的BC患者被前瞻性纳入研究。通过模型拟合和实验获得的+3.5 ppm的z谱之间的差异分析，实现了apt特异性信号量化。采用单因素分析确定与组织病理学特征和pCR相关的APT#值。通过受试者工作特征曲线下面积（AUC）分析，评估APTWI-DIGITAL对组织病理特征的诊断价值，并评估pCR的预测性能。分析最终纳入123例BC患者（平均年龄52 岁±9 [SD]）， 43例接受新辅助化疗（NAC）， 15例获得pCR的患者。预处理组APT#值对KI67增殖指数（P = 0.01,AUC = 0.69）和PR （P = 0.045,AUC = 0.60）阳性状态的判断表现合理。在NAC组中，pCR参与者的APT#值在T1处呈显著下降趋势（P = 0.01,AUC = 0.80），在其他时间点pCR与非pCR之间无显著差异。研究结果表明，aptwi差异分析可能是有用的成像生物标志物，用于表征BC患者的免疫组织化学生物标志物和预测pCR到NAC。

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引用次数: 0

Accuracy and precision of random walk with barrier model fitting: Simulations and applications in head and neck cancers 具有屏障模型拟合的随机行走的准确性和精度：头颈癌的模拟和应用。

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-04-01 Epub Date: 2025-12-16 DOI: 10.1016/j.mri.2025.110597

Jiaren Zou , Yue Cao

Random Walk with Barrier Model (RWBM) can quantify microstructural parameters (free diffusivity, cell size, and membrane permeability) in head and neck cancers (HNCs) using time-dependent diffusion MRI. However, model fitting remains challenging due to limited number of measurements, low signal-to-noise ratio (SNR) and complex nonlinear biophysical models. In this work, we numerically evaluated RWBM fitting performance under a clinically feasible imaging protocol by comparing fits to the short-time-limit expression (STL-RWBM) and to the general RWBM across a broad range of SNRs. We also examined the model fitting degeneracy and fitting landscape for both fitting methods to elucidate their fitting behaviors. Numerical findings were further compared with model-fitting results from HNC patient data. We observed that under clinically relevant SNRs, fitting the STL-RWBM provided low-variance estimates of free diffusivity and membrane permeability, with biases comparable to those obtained from fitting the general RWBM. However, the general RWBM yielded low-bias estimates for cell size. The flat and tube-like fitting landscapes of the general RWBM led to high variance, frequent convergence to boundary constraints and spurious correlation among fitted parameters in vivo. The more restricted fitting landscape of the STL-RWBM substantially reduced variance. Both fitting methods produced cell size estimates in HNCs that were consistent with prior pathological findings. In conclusion, this work provided a comprehensive analysis of RWBM fitting in clinical settings and may guide optimizations of data acquisition and model fitting methods.

随机行走屏障模型（RWBM）可以量化头颈癌（HNCs）的显微结构参数（自由扩散率、细胞大小和膜通透性）。然而，由于测量数量有限，低信噪比（SNR）和复杂的非线性生物物理模型，模型拟合仍然具有挑战性。在这项工作中，我们通过比较短时限表达（STL-RWBM）和一般RWBM在广泛信噪比范围内的拟合，在临床可行的成像方案下对RWBM的拟合性能进行了数值评估。我们还研究了两种拟合方法的模型拟合退化性和拟合景观，以阐明它们的拟合行为。数值结果进一步与HNC患者数据的模型拟合结果进行了比较。我们观察到，在临床相关信噪比下，拟合STL-RWBM提供了自由扩散率和膜透性的低方差估计，其偏差与拟合一般RWBM所得的偏差相当。然而，一般RWBM对细胞大小的估计偏差较低。一般RWBM的平面和管状拟合景观导致体内拟合参数之间的高方差，频繁收敛于边界约束和虚假相关性。STL-RWBM更严格的拟合景观大大减少了方差。两种拟合方法产生的HNCs细胞大小估计值与先前的病理结果一致。总之，这项工作提供了临床环境下RWBM拟合的全面分析，并可能指导数据采集和模型拟合方法的优化。

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引用次数: 0

Microscopic Propagator Imaging with diffusion MRI 扩散MRI显微传播体成像。

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-04-01 Epub Date: 2025-12-29 DOI: 10.1016/j.mri.2025.110607

Tommaso Zajac , Gloria Menegaz , Marco Pizzolato

Microscopic Propagator Imaging (MPI) is a novel diffusion MRI technique that estimates properties, referred to as indices, of the microscopic propagator. This is the probability distribution of water displacements within tissue microstructures. Unlike conventional mean apparent propagator methods, MPI is designed to minimize the sensitivity of indices to mesoscopic confounds such as axonal orientation dispersion, yielding diagnostic maps that more directly reflect presence, integrity, and shape of microstructures rather than their directional arrangement within the voxel. The method is implemented as a machine learning framework that exploits zonal relationships among spherical harmonic coefficients of multi-shell diffusion data to map such data to the microscopic propagator indices. Applied to human brain data, MPI yields reliable voxelwise estimates, with resulting maps exhibiting expected spatial patterns and systematic differences relative to the corresponding mean apparent propagator indices. These findings suggest that MPI provides microscopic-specific and complementary information beyond classical propagator methods, with potential to improve the characterization of brain tissue microstructure.

显微传播体成像（MPI）是一种新型的扩散MRI技术，用于估计微观传播体的属性，即指数。这是水在组织微观结构中位移的概率分布。与传统的平均表观传播子方法不同，MPI旨在最大限度地降低指标对介观混淆（如轴突方向分散）的敏感性，从而产生更直接反映微观结构的存在、完整性和形状的诊断图，而不是它们在体素内的方向排列。该方法作为一个机器学习框架实现，利用多壳扩散数据的球面调和系数之间的纬向关系将这些数据映射到微观传播子指标。将MPI应用于人类大脑数据，可以产生可靠的体素估计，所得到的地图显示了预期的空间模式和相对于相应的平均表观传播因子指数的系统差异。这些发现表明，MPI提供了超越经典传播体方法的微观特异性和互补信息，具有改善脑组织微观结构表征的潜力。

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引用次数: 0

Non-contrast free-running high-resolution volumetric multi-slab cardiac cine MRI at 3 T 非造影剂自由运行高分辨率多板心脏MRI在3t

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-04-01 Epub Date: 2025-12-09 DOI: 10.1016/j.mri.2025.110591

Chenhao Gao, Fan Yang, Zhihao Xue, Junyao Zhang, Zhuo Chen, Sirui Huo, Juan Gao, Yixin Emu, Haiyang Chen, Chenxi Hu

Free-running self-gated 3D cardiac cine imaging is highly desirable for volumetric, high-resolution, breath-hold-free assessment of left ventricular (LV) function. However, its implementation at 3 T remains challenging due to specific absorption rate (SAR) constraints and reduced myocardium-blood contrast. In this study, we propose a novel non-contrast, free-running, self-gated 3D gradient-echo (GRE) cine sequence for 3 T imaging, which acquires multi-slab data using a pseudo-radial Cartesian trajectory with a 1.5 mm slice thickness. To address respiratory motion, a locally low-rank motion-corrected image reconstruction algorithm was developed. Fifteen participants underwent imaging with the proposed multi-slab 3D cine sequence and conventional 2D cine sequences. Additionally, single-slab 3D cine data were acquired in 10 participants. Various image quality metrics (signal-to-noise ratio, contrast-to-noise ratio, myocardial sharpness, and residual artefact) and LV volumetric parameters (end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF)) were compared between the different methods. Results demonstrated that the proposed multi-slab 3D cine method provided significantly superior image quality compared to the single-slab 3D approach (myocardial sharpness: 2.82 ± 0.42 vs. 1.58 ± 0.46, P = 0.005; residual artefact: 2.58 ± 0.26 vs. 1.13 ± 0.21, P = 0.005) due to the improvement of image contrast. Furthermore, the multi-slab 3D cine sequence exhibited good agreement and correlation with the reference 2D cine method in terms of volumetric measures (EDV: 140.3 ± 19.9 mL vs. 139.3 ± 20.0 mL, P = 0.357, r = 0.976; ESV: 56.7 ± 11.8 mL vs. 57.7 ± 10.2 mL, P = 0.259, r = 0.964; EF: 59.8 % ± 4.9 % vs. 58.7 % ± 3.7 %, P = 0.073, r = 0.907). In conclusion, the proposed multi-slab 3D cine framework enables free-running 3 T cine imaging with whole-heart coverage and high through-plane resolution. Although myocardium-blood contrast is reduced compared to 2D breath-hold cine, the retained contrast is sufficient to evaluate LV function.

自由运行的自门控3D心脏电影成像是非常理想的容积，高分辨率，无呼吸的左心室（LV）功能评估。然而，由于特定吸收率（SAR）的限制和心肌-血液对比降低，在3t时的实施仍然具有挑战性。在这项研究中，我们提出了一种新的无对比度、自由运行、自门控的3D梯度回波（GRE）序列，用于3t成像，该序列使用1.5 mm层厚的伪径向笛卡尔轨迹获取多层数据。针对呼吸运动，提出了一种局部低秩运动校正图像重建算法。15名参与者接受了拟议的多板3D电影序列和传统的2D电影序列的成像。此外，还获得了10名参与者的单平板三维电影数据。各种图像质量指标（信噪比、对比噪声比、心肌清晰度和残余伪影）和左室容积参数（舒张末期容积（EDV）、收缩末期容积（ESV）和射血分数（EF））在不同方法之间进行了比较。结果表明，由于图像对比度的提高，多板三维成像方法的图像质量明显优于单板三维成像方法（心肌清晰度：2.82±0.42 vs. 1.58±0.46,P = 0.005；残余伪影：2.58±0.26 vs. 1.13±0.21,P = 0.005）。此外，在容积测量方面，多板三维电影序列与参考2D电影方法表现出良好的一致性和相关性（EDV: 140.3±19.9 mL对139.3±20.0 mL, P = 0.357, r = 0.976; ESV: 56.7±11.8 mL对57.7±10.2 mL, P = 0.259, r = 0.964; EF: 59.8%±4.9%对58.7%±3.7%,P = 0.073, r = 0.907）。总之，所提出的多板3D电影框架可以实现全心脏覆盖和高透平面分辨率的自由运行的3t电影成像。虽然与2D屏气片相比，心肌-血液对比降低，但保留的对比足以评估左室功能。

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引用次数: 0

Multicenter validation of amide proton transfer imaging for the classification of adult-type diffuse gliomas 酰胺质子转移成像对成人型弥漫性胶质瘤分级的多中心验证

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-04-01 Epub Date: 2025-12-24 DOI: 10.1016/j.mri.2025.110599

Tongling Jiang , Minghao Wu , Junjiao Hu , Hu Guo , Xiaoyue Ma , Yaou Liu , Yi Zhang

Accurate classification of adult-type diffuse gliomas is essential for treatment planning, particularly following the 2021 WHO classification update. While amide proton transfer (APT) imaging shows promise, multicenter validation is needed to establish its clinical utility. This study aims to evaluate the multicenter performance of the APT-weighted (APTw) metric for differentiating genotypes, grades, and subtypes of adult-type diffuse gliomas. MRI and clinical data were collected from three centers between July 2020 and January 2024. A standardized whole-brain SPACE CEST imaging protocol was used, and molecular diagnoses were confirmed. Tumor core regions were delineated on T2-weighted images, and multi-modality data were co-registered to T1-weighted images. Mean APTw values were assessed for IDH genotyping and grading among three centers, and for subtyping across two centers, using unpaired t-tests and receiver operating characteristic (ROC) curve analysis. A total of 123 patients (mean age: 48 ± 12 years; 67 males) were included. APTw indices were significantly higher in IDH-wildtype and high-grade gliomas compared to IDH-mutant and low-grade groups (p < 0.01). ROC analysis demonstrated strong classification performance: for IDH genotyping, the pooled area under the ROC curve (AUC) value was 0.84 (individual centers: 0.86, 0.84, and 0.93); for glioma grading, the pooled AUC was 0.83 (individual centers: 0.86, 0.84, and 0.83). Subtyping results showed good performance, particularly in differentiating glioblastomas from oligodendrogliomas (AUC: 0.93) and astrocytomas (AUC: 0.81). APT imaging effectively differentiated glioma grades and IDH mutations across centers, demonstrating robust multicenter performance. However, challenges remain in differentiating specific glioma subtypes.

成人型弥漫性胶质瘤的准确分类对于治疗计划至关重要，特别是在2021年世卫组织分类更新之后。虽然酰胺质子转移（APT）成像显示出希望，但需要多中心验证来建立其临床应用。本研究旨在评估apt加权（APTw）指标在区分成人型弥漫性胶质瘤的基因型、分级和亚型方面的多中心表现。2020年7月至2024年1月期间从三个中心收集MRI和临床数据。采用标准化全脑SPACE CEST成像方案，并进行分子诊断。在t2加权图像上描绘肿瘤核心区域，并将多模态数据共同配准到t1加权图像上。采用非配对t检验和受试者工作特征（ROC）曲线分析，评估三个中心之间IDH基因分型和分级的平均APTw值，以及两个中心之间的亚型分型。共纳入123例患者，平均年龄48±12岁，男性67例。与idh突变组和低级别组相比，idh野生型和高级别胶质瘤的APTw指数显著升高（p < 0.01）。ROC分析显示了较强的分类能力：对于IDH基因分型，ROC曲线下合并面积（AUC）值为0.84（个体中心分别为0.86、0.84和0.93）；对于胶质瘤分级，合并AUC为0.83（个别中心分别为0.86、0.84和0.83）。分型结果表现良好，特别是在胶质母细胞瘤与少突胶质胶质瘤（AUC: 0.93）和星形细胞瘤（AUC: 0.81）的区分上。APT成像可以有效地区分胶质瘤分级和IDH突变，显示出强大的多中心表现。然而，在区分特定的胶质瘤亚型方面仍然存在挑战。

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引用次数: 0

The nature and interpretation of BOLD signals in white matter - A review 脑白质BOLD信号的性质及解释综述。

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-04-01 Epub Date: 2025-12-16 DOI: 10.1016/j.mri.2025.110596

J.C. Gore , M. Li , K.G. Schilling , L. Xu , Y. Li , Z. Zu , A.W. Anderson , Z. Ding , Y. Gao

This review summarizes selected recent findings demonstrating the dependence of blood oxygenation level dependent (BOLD) signals in white matter (WM) on tissue microstructure, composition, vascular properties and metabolism, as well as their relationships to fMRI signals within gray matter (GM) networks. BOLD signals in WM are robustly detectable after a stimulus, and at rest their temporal variations reveal synchronized networks and correlated neural activities involving both WM and GM. However, to date, most analyses of brain fMRI data have ignored WM signals, and often have removed them as nuisance regressors. However, emerging evidence clearly demonstrates that WM BOLD signals represent potentially important and heretofore overlooked indicators of neural activities that are intimately related to how cortical regions communicate, and so should be incorporated into more complete models of brain functional organization. Here we review recent work that contributes to our understanding of their interpretation and significance.

The factors that affect the magnitude and other characteristics of BOLD responses in WM are becoming more clear, and recent studies have demonstrated and quantified the relationships between BOLD signals and vascular and microstructural properties of WM tracts. These relationships depend on the degree of myelination and neurite and mitochondrial densities, but they also are qualitatively different when comparing different fiber types, notably association versus projection fibers. Some fully myelinated fibers appear to not show detectable BOLD effects. The relationships between WM and GM BOLD signals, the contributions of GM resting state correlations and signals to WM BOLD signals, and the engagement of WM in GM networks, are also becoming more clear. These findings supplement the growing literature demonstrating practical, clinical applications of BOLD in WM. The goal of this review is to highlight recent research that demonstrates how WM and GM activities are related, and to stimulate further investigations that may produce a more complete model of brain organization.

这篇综述总结了最近的一些研究结果，这些发现证明了白质（WM）中血氧水平依赖（BOLD）信号对组织微观结构、组成、血管特性和代谢的依赖性，以及它们与灰质（GM）网络中fMRI信号的关系。在刺激后，WM中的BOLD信号可以被稳健地检测到，并且在静止状态下，它们的时间变化揭示了涉及WM和GM的同步网络和相关神经活动。然而，迄今为止，大多数脑功能磁共振数据分析都忽略了WM信号，并且经常将其作为讨厌的回归量去除。然而，新出现的证据清楚地表明，WM BOLD信号代表了与皮层区域如何交流密切相关的神经活动的潜在重要和迄今为止被忽视的指标，因此应该纳入更完整的脑功能组织模型。在这里，我们回顾最近的工作，有助于我们的解释和意义的理解。影响WM中BOLD反应的大小和其他特征的因素越来越清楚，最近的研究已经证明并量化了BOLD信号与WM束血管和微观结构特性之间的关系。这些关系取决于髓鞘、神经突和线粒体密度的程度，但在比较不同纤维类型时，它们也有质的不同，特别是关联纤维和投射纤维。一些完全有髓鞘纤维似乎没有可检测到的BOLD效应。WM和GM BOLD信号之间的关系，GM静息状态相关和信号对WM BOLD信号的贡献，以及WM在GM网络中的参与也变得越来越清楚。这些发现补充了越来越多的文献证明BOLD在WM中的实际临床应用。这篇综述的目的是强调最近的研究，证明WM和GM活动是如何相关的，并刺激进一步的研究，可能会产生一个更完整的大脑组织模型。

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Nesterov accelerated spectral conjugate gradient algorithm for magnetic resonance imaging with TV regularisation 带电视正则化的磁共振成像Nesterov加速谱共轭梯度算法。

IF 2 4区医学 Q2 RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING

Magnetic resonance imaging

Pub Date : 2026-04-01 Epub Date: 2025-12-26 DOI: 10.1016/j.mri.2025.110604

YueHong Ding , ZhiBin Zhu , Shuo Wang , BenXin Zhang

Magnetic Resonance Imaging (MRI) as a representative of noninvasive medical imaging, it has excellent soft tissue resolution, multi-parameter imaging capability and no radiation, thus it has been widely used in the fields of disease diagnosis, treatment and drug development. However, MRI technology still has problems such as long time consuming, sensitive to motion artefacts, and difficult to balance the imaging effect and speed. In this paper, a Nesterov accelerated spectral conjugate gradient algorithm (TV_NASCG) for MRI with TV regularisation is established from optimising reconstruction algorithms based on Total Variation (TV) regularised MRI model. The algorithm is based on a set of conjugate and spectral parameters proposed in this paper, and inspired by Nesterov acceleration technique, a set of Nesterov acceleration extrapolation step and acceleration parameter are proposed. In this paper, we also use step size acceleration technique and Powell restart strategy to further improve performance of the algorithm. In addition, we give a convergence analysis of TV_NASCG algorithm, which proves that it is sufficiently descent and globally convergent. Finally, in order to verify MRI performance of TV_NASCG algorithm, it was tested in MRI experiment and compared with other algorithms, and experimental results show that TV_NASCG algorithm can improve MRI quality and shorten imaging time.

磁共振成像（MRI）作为无创医学成像的代表，具有优异的软组织分辨率、多参数成像能力和无辐射等优点，在疾病诊断、治疗和药物开发等领域得到了广泛的应用。然而，MRI技术仍然存在耗时长、对运动伪影敏感、成像效果与速度难以平衡等问题。本文基于全变分（TV）正则化MRI模型，对重构算法进行优化，建立了一种用于TV正则化MRI的Nesterov加速谱共轭梯度算法（TV_NASCG）。该算法基于本文提出的一组共轭参数和谱参数，并受Nesterov加速度技术的启发，提出了一组Nesterov加速度外推步长和加速度参数。在本文中，我们还使用步长加速技术和Powell重启策略来进一步提高算法的性能。此外，我们还对TV_NASCG算法进行了收敛性分析，证明了该算法具有充分下降性和全局收敛性。最后，为了验证TV_NASCG算法的MRI性能，在MRI实验中对其进行了测试，并与其他算法进行了比较，实验结果表明，TV_NASCG算法可以提高MRI质量，缩短成像时间。

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引用次数: 0