title: Combined use of diffusion tensor tractography and multifused contrast-enhanced FIESTA for predicting facial and cochlear nerve positions in relation to vestibular schwannoma.
abstract: OBJECTIVE
  The authors assessed whether the combined use of diffusion tensor tractography (DTT) and contrast-enhanced (CE) fast imaging employing steady-state acquisition (FIESTA) could improve the accuracy of predicting the courses of the facial and cochlear nerves before surgery.
  
  
  METHODS
  The population was composed of 22 patients with vestibular schwannoma in whom both the facial and cochlear nerves could be identified during surgery. According to DTT, depicted fibers running from the internal auditory canal to the brainstem were judged to represent the facial or vestibulocochlear nerve. With regard to imaging, the authors investigated multifused CE-FIESTA scans, in which all 3D vessel models were shown simultaneously, from various angles. The low-intensity areas running along the tumor from brainstem to the internal auditory canal were judged to represent the facial or vestibulocochlear nerve.
  
  
  RESULTS
  For all 22 patients, the rate of fibers depicted by DTT coinciding with the facial nerve was 13.6% (3/22), and that of fibers depicted by DTT coinciding with the cochlear nerve was 63.6% (14/22). The rate of candidates for nerves predicted by multifused CE-FIESTA coinciding with the facial nerve was 59.1% (13/22), and that of candidates for nerves predicted by multifused CE-FIESTA coinciding with the cochlear nerve was 4.5% (1/22). The rate of candidates for nerves predicted by combined DTT and multifused CE-FIESTA coinciding with the facial nerve was 63.6% (14/22), and that of candidates for nerves predicted by combined DTT and multifused CE-FIESTA coinciding with the cochlear nerve was 63.6% (14/22). The rate of candidates predicted by DTT coinciding with both facial and cochlear nerves was 0.0% (0/22), that of candidates predicted by multifused CE-FIESTA coinciding with both facial and cochlear nerves was 4.5% (1/22), and that of candidates predicted by combined DTT and multifused CE-FIESTA coinciding with both the facial and cochlear nerves was 45.5% (10/22).
  
  
  CONCLUSIONS
  By using a combination of DTT and multifused CE-FIESTA, the authors were able to increase the number of vestibular schwannoma patients for whom predicted results corresponded with the courses of both the facial and cochlear nerves, a result that has been considered difficult to achieve by use of a single modality only. Although the 3D image including these prediction results helped with comprehension of the 3D operative anatomy, the reliability of prediction remains to be established.
authors.affiliation: Departments of 1 Neurosurgery.
authors.forename: Masanori
authors.initials: M
authors.lastname: Yoshino
authors.affiliation: Departments of 1 Neurosurgery.
authors.forename: Taichi
authors.initials: T
authors.lastname: Kin
authors.affiliation: Departments of 1 Neurosurgery.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ito
authors.affiliation: Clinical Information Engineering, and.
authors.forename: Toki
authors.initials: T
authors.lastname: Saito
authors.affiliation: Departments of 1 Neurosurgery.
authors.forename: Daichi
authors.initials: D
authors.lastname: Nakagawa
authors.affiliation: Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan; and.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ino
authors.affiliation: Department of Neurosurgery, Asahikawa Medical University, Asahikawa, Japan.
authors.forename: Kyousuke
authors.initials: K
authors.lastname: Kamada
authors.affiliation: Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan; and.
authors.forename: Harushi
authors.initials: H
authors.lastname: Mori
authors.affiliation: Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan; and.
authors.forename: Akira
authors.initials: A
authors.lastname: Kunimatsu
authors.affiliation: Departments of 1 Neurosurgery.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Nakatomi
authors.affiliation: Clinical Information Engineering, and.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Oyama
authors.affiliation: Departments of 1 Neurosurgery.
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Saito
mesh_terms: D000293:Adolescent; D000328:Adult; D003056:Cochlear Nerve; D015331:Cohort Studies; D003287:Contrast Media; D056324:Diffusion Tensor Imaging; D005154:Facial Nerve; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009464:Neuroma, Acoustic / Q000175:diagnosis* / Q000601:surgery; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: 3DRA = 3D rotational angiography; CE = contrast-enhanced; CE-FIESTA; DTT = diffusion tensor tractography; ESE-DNAP = electric stimulielicited dorsal cochlear nucleus action potential; FIESTA = fast imaging employing steady-state acquisition; MRA = MR angiography; TOF = time of flight; TRICKS = time-resolved imaging of contrast kinetics; VS = vestibular schwannoma; cochlear nerve; diagnostic and operative techniques; diffusion tensor tractography; facial nerve; vestibular schwannoma