在3T场强下对腰椎脊髓的单次激发回波平面成像(EPI)与二维导航、多次激发EPI扩散张量成像采集进行比较。
Comparing single-shot EPI and 2D-navigated, multi-shot EPI diffusion tensor imaging acquisitions in the lumbar spinal cord at 3T.
作者信息
Cronin Alicia E, Combes Anna, Narisetti Lipika, Sweeney Grace, Prock Logan, Houston Delaney, Seehorn Caroline, Schilling Kurt G, Robison Ryan K, Smith Seth A, O'Grady Kristin P
机构信息
Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; NMR Research Unit, Queen Square Multiple Sclerosis Centre, UCL Queen Square Institute of Neurology, University College London, London, UK.
出版信息
Magn Reson Imaging. 2025 Oct;122:110445. doi: 10.1016/j.mri.2025.110445. Epub 2025 Jun 4.
Diffusion tensor imaging (DTI) can provide insights into spinal cord microstructure in health and disease; however, its application has been largely limited to cervical spinal segments using single-shot echo-planar imaging (EPI) diffusion-weighted MRI acquisitions. In this work, we evaluate a multi-shot EPI diffusion-weighted acquisition with reduced field-of-view (FOV) and 2D-navigated motion correction applied in the lumbar spinal cord of healthy volunteers, and compare image quality, geometric distortions, and quantitative DTI indices to those obtained with conventional, single-shot EPI diffusion-weighted MRI in a distinct, age/sex-matched healthy cohort. At 3 Tesla, 25 and 27 healthy participants were imaged using the single-shot and multi-shot EPI readouts with diffusion weighting, respectively, with matching resolution and comparable scan time. Seven participants underwent both diffusion acquisitions and were included in both cohorts. DTI indices were compared between the multi-shot and single-shot cohorts. Image signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) between gray and white matter, geometric distortions, and within-subject bias between the acquisitions were also assessed. The lumbar spinal cord diffusion indices derived from both cohorts were comparable to those in previous studies using single-shot EPI, though within-subject analysis demonstrated a systematic bias between the acquisitions in gray and white matter DTI measures, indicating these acquisitions are not interchangeable within a study. The multi-shot quantitative DTI maps demonstrated a significant reduction in image artifacts (i.e., distortions and blurring) and higher SNR and CNR compared to single-shot images. Overall, the reduced FOV, 2D-navigated, motion-corrected multi-shot acquisition demonstrated improved DTI quality metrics compared to single-shot, supporting its application for the lumbar spinal cord region.
扩散张量成像(DTI)能够为健康和疾病状态下的脊髓微观结构提供深入见解;然而,其应用在很大程度上局限于使用单次激发回波平面成像(EPI)扩散加权磁共振成像(MRI)采集来研究颈段脊髓。在本研究中,我们评估了一种在健康志愿者腰段脊髓中应用的具有缩小视野(FOV)和二维导航运动校正的多次激发EPI扩散加权采集,并将图像质量、几何畸变和定量DTI指标与在一个年龄/性别匹配的不同健康队列中通过传统单次激发EPI扩散加权MRI获得的指标进行比较。在3特斯拉场强下,分别使用单次激发和多次激发EPI读出序列并施加扩散加权对25名和27名健康参与者进行成像,两者具有匹配的分辨率和可比的扫描时间。七名参与者接受了两种扩散采集,并被纳入两个队列。比较了多次激发和单次激发队列之间的DTI指标。还评估了图像信噪比(SNR)、灰质和白质之间的对比噪声比(CNR)、几何畸变以及采集之间的受试者内偏差。两个队列得出的腰段脊髓扩散指标与先前使用单次激发EPI的研究中的指标相当,尽管受试者内分析表明在灰质和白质DTI测量的采集之间存在系统性偏差,这表明在一项研究中这些采集不可互换。与单次激发图像相比,多次激发定量DTI图显示图像伪影(即畸变和模糊)显著减少,SNR和CNR更高。总体而言,与单次激发相比,缩小视野、二维导航、运动校正的多次激发采集显示出改善的DTI质量指标,支持其在腰段脊髓区域的应用。