title: Feasibility of diffusion tensor tractography for preoperative prediction of the location of the facial and vestibulocochlear nerves in relation to vestibular schwannoma.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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%).
  
  
  CONCLUSIONS
  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.
authors: Department of Neurosurgery, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan, ymasa-tky@umin.ac.jp.
authors: Masanori
authors: M
authors: Yoshino
authors: Taichi
authors: T
authors: Kin
authors: Akihiro
authors: A
authors: Ito
authors: Toki
authors: T
authors: Saito
authors: Daichi
authors: D
authors: Nakagawa
authors: Kenji
authors: K
authors: Ino
authors: Kyousuke
authors: K
authors: Kamada
authors: Harushi
authors: H
authors: Mori
authors: Akira
authors: A
authors: Kunimatsu
authors: Hirofumi
authors: H
authors: Nakatomi
authors: Hiroshi
authors: H
authors: Oyama
authors: Nobuhito
authors: N
authors: Saito
mesh_terms: D000293:Adolescent; D000328:Adult; D016880:Anisotropy; D003056:Cochlear Nerve / Q000473:pathology; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005154:Facial Nerve / Q000033:anatomy & histology*; D005240:Feasibility Studies; D005260:Female; D006320:Hearing Tests; D006801:Humans; D007091:Image Processing, Computer-Assisted; D064795:Intraoperative Neurophysiological Monitoring; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000473:pathology* / Q000601:surgery*; D019635:Neurosurgical Procedures / Q000379:methods; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology; D016896:Treatment Outcome; D000159:Vestibulocochlear Nerve / Q000033:anatomy & histology*; D055815:Young Adult