Division of Radiology and Nuclear Medicine, Sapporo Medical University Hospital, Chuo-ku, South-1, West-16, Sapporo, Hokkaido, Japan.
Department of Neurosurgery, Osaka Medical College, 2-7, Daigaku-cho, Takatsuki, Osaka, Japan.
Acta Neurochir (Wien). 2021 Mar;163(3):619-624. doi: 10.1007/s00701-020-04511-6. Epub 2020 Jul 29.
The cerebellum communicates with the cerebral cortex via the superior, middle, and inferior cerebellar peduncles (CPs). To preserve the structure and function of the brainstem and cerebellum, which is compressed in various pathological conditions, it is important to delineate the spatial interrelationship of the CPs for presurgical planning and intraoperative guidance. Diffusion tensor tractography (DTT) is a technique capable of depicting the major fiber bundles in CPs. However, routine use of this technology for brainstem visualization remains challenging due to the anatomical smallness and complexity of the brainstem and susceptibility-induced image distortions. Here, we attempt to visualize CPs using high-resolution DTT in a commercial equipment for the application of this technique in normal clinical settings. DTT and fast imaging employing steady-state acquisition-cycled phases (FIESTA) of the whole brainstem were performed. We rendered the DTT fiber bundle using a region-of-interest-based fiber tracking method onto the structural image generated in FIESTA by automatic image coregistration. Fibers of the CPs were clearly visualized by DTT. The DTT-FIESTA overlaid image revealed the cross-sectional and three-dimensional anatomy of the pyramidal tract and the ascending sensory fibers, in addition to the CPs. This could indicate a geometrical relationship of these fibers in the brainstem. The CPs could be visualized clearly using DTT within clinically acceptable scanning times. This method of visualizing the exact pathway of fiber bundles and cranial nerves in the skull base helps in the planning of surgical approaches.
小脑通过上、中、下小脑脚（CPs）与大脑皮层进行交流。为了在各种病理情况下保持脑干和小脑的结构和功能，重要的是要描绘出 CPs 的空间相互关系，以便进行术前规划和术中指导。弥散张量纤维束成像（DTT）是一种能够描绘 CPs 中主要纤维束的技术。然而，由于脑干的解剖学小和复杂性以及感应诱导的图像失真，常规使用这项技术来可视化脑干仍然具有挑战性。在这里，我们尝试在商业设备中使用高分辨率 DTT 来可视化 CPs，以将这项技术应用于正常的临床环境。对整个脑干进行 DTT 和使用稳态采集循环相位（FIESTA）的快速成像。我们使用基于感兴趣区域的纤维跟踪方法将 DTT 纤维束渲染到 FIESTA 生成的结构图像上，自动进行图像配准。DTT 清晰地显示了 CPs 的纤维。DTT-FIESTA 叠加图像显示了除 CPs 之外，还有锥体束和上行感觉纤维的横断和三维解剖结构。这可能表明这些纤维在脑干中的几何关系。在可接受的临床扫描时间内，DTT 可以清晰地显示 CPs。这种可视化颅神经和颅神经在颅底的确切途径的方法有助于手术入路的规划。
