Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xuanwu District, Beijing, 100053, China.
Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China.
BMC Neurol. 2019 Nov 28;19(1):302. doi: 10.1186/s12883-019-1537-6.
Visual field defects caused by injury to Meyer's loop (ML) are common in patients undergoing anterior temporal lobectomy during epilepsy surgery. Evaluation of the anatomical shapes of the curving, fanning and sharp angles of ML to guide surgeries is important but still challenging for diffusion tensor imaging. We present an advanced diffusion data-based ML atlas and labeling protocol to reproduce anatomical features in individuals within a short time.
Thirty Massachusetts General Hospital-Human Connectome Project (MGH-HCP) diffusion datasets (ultra-high magnetic gradient & 512 directions) were warped to standard space. The resulting fibers were projected together to create an atlas. The anatomical features and the tractography correspondence rates were evaluated in 30 MGH-HCP individuals and local diffusion spectrum imaging data (eight healthy subjects and six hippocampal sclerosis patients).
In the atlas, features of curves, sharp angles and fanning shapes were adequately reproduced. The distances from the anterior tip of the temporal lobe to the anterior ridge of Meyer's loop were 23.1 mm and 26.41 mm on the left and right sides, respectively. The upper and lower divisions of the ML were revealed to be twisting. Eighty-eight labeled sides were achieved, and the correspondence rates were 87.44% ± 6.92, 80.81 ± 10.62 and 72.83% ± 14.03% for MGH-HCP individuals, DSI-healthy individuals and DSI-patients, respectively.
Atlas-labeled ML is comparable to high angular resolution tractography in healthy or hippocampal sclerosis patients. Therefore, rapid identification of the ML location with a single modality of T1 is practical. This protocol would facilitate functional studies and visual field protection during neurosurgery.
在癫痫手术中进行前颞叶切除术时，Meyer 袢（ML）损伤引起的视野缺损很常见。评估 ML 的弯曲、扇形和锐角的解剖形状以指导手术很重要，但对于弥散张量成像来说仍然具有挑战性。我们提出了一种基于先进弥散数据的 ML 图谱和标记方案，可以在短时间内重现个体的解剖特征。
将 30 个麻省总医院-人类连接组计划（MGH-HCP）弥散数据集（超高磁场梯度和 512 个方向）变形到标准空间。将得到的纤维一起投影，创建一个图谱。在 30 个 MGH-HCP 个体和局部弥散谱成像数据（8 个健康受试者和 6 个海马硬化患者）中评估解剖特征和束追踪对应率。
在图谱中，曲线、锐角和扇形形状的特征得到了充分再现。左、右侧颞叶前尖端到 Meyer 袢前嵴的距离分别为 23.1mm 和 26.41mm。ML 的上下部分被揭示为扭曲。共标记了 88 个侧面，对应率分别为 87.44%±6.92%、80.81%±10.62%和 72.83%±14.03%，用于 MGH-HCP 个体、DSI-健康个体和 DSI-患者。
图谱标记的 ML 与健康或海马硬化患者的高角度分辨率束追踪具有可比性。因此，用 T1 单一模态快速识别 ML 的位置是可行的。该方案将有助于神经外科中的功能研究和视野保护。
