Yoshino Masanori, Kin Taichi, Ito Akihiro, Saito Toki, Nakagawa Daichi, Ino Kenji, Kamada Kyousuke, Mori Harushi, Kunimatsu Akira, Nakatomi Hirofumi, Oyama Hiroshi, Saito Nobuhito
Department of Neurosurgery, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan,
Acta Neurochir (Wien). 2015 Jun;157(6):939-46; discussion 946. doi: 10.1007/s00701-015-2411-y. Epub 2015 Apr 12.
According to recent findings, diffusion tensor tractography (DTT) only allows prediction of facial nerve location in relation to vestibular schwannoma (VS) with high probability. However, previous studies have not mentioned why only the facial nerve was selectively visualized. Our previous report investigated the optimal conditions of DTT for normal facial and vestibulocochlear nerves. In the present study, we applied the optimal conditions of DTT to VS patients to assess the feasibility of DTT for the facial and vestibulocochlear nerves.
We investigated 11 patients with VS who underwent tumor resection. Visualized tracts were compared with locations of the facial and cochlear nerves as identified by intraoperative electrophysiological monitoring.
With the proposed method, visualized tracts corresponded to pathway area of the facial or cochlear nerves in nine of 11 patients (81.8%); specifically, to the pathway area of the facial nerve in three of 11 patients (27.3%), and to the pathway area of the cochlear nerve in six of 11 patients (54.5%).
We visualized facial or vestibulocochlear nerves in nine of 11 patients (81.8%). For the first time, DTT proved able to visualize not only the facial nerve but also the vestibulocochlear nerve in VS patients. Despite our findings, good methods for distinguishing whether a visualized nerve tract represents facial nerve, vestibulocochlear nerve, or only noise remain unavailable. Close attention should therefore be paid to the interpretation of visualized fibers.
根据最近的研究结果，弥散张量纤维束成像（DTT）仅能以较高概率预测面神经相对于前庭神经鞘瘤（VS）的位置。然而，以往的研究并未提及为何仅选择性地显示了面神经。我们之前的报告研究了正常面神经和前庭蜗神经的DTT最佳条件。在本研究中，我们将DTT的最佳条件应用于VS患者，以评估DTT对面神经和前庭蜗神经的可行性。
我们调查了11例接受肿瘤切除的VS患者。将显示的纤维束与术中电生理监测确定的面神经和蜗神经位置进行比较。
采用本方法，11例患者中有9例（81.8%）显示的纤维束与面神经或蜗神经的走行区域相对应；具体而言，11例患者中有3例（27.3%）与面神经的走行区域相对应，11例患者中有6例（54.5%）与蜗神经的走行区域相对应。
我们在11例患者中的9例（81.8%）显示了面神经或前庭蜗神经。首次证明DTT不仅能够显示VS患者的面神经，还能显示前庭蜗神经。尽管有这些发现，但仍缺乏区分显示的神经纤维束是代表面神经、前庭蜗神经还是仅仅是噪声的良好方法。因此，应密切关注对显示纤维的解读。
