Surgical study of microvascular decompression for facial spasm

Guo Hongchuan; Zhao Chengxin; Song Gang; Li Mingchu; Zhang Qiuhang

doi:10.11850/j.issn.1009-122X.2016.10.003

Abstract：Objective To study whether patients with facial spasm had intracranial vascular compression to provide evidence for microvascular decompression ( MVD ) . Methods Clinical data of 108 facial spasm patients undergoing MVD were analyzed retrospectively. The preoperative imaging was used to check the existence of offending vessels. The whole process of the facial nerve from the root exit zone (REZ) at the end of the brainstem to the entry of the internal auditory canal was exposed by surgery via suboccipital retrosigmoid sinus approach. And then Teflon was placed on the compression position. Results There were 88 patients with offending vessel compression at facial nerve REZ. Six patients had both offending vessel at the facial nerve REZ and a corner which was formed by pushing or pulling of offending vascular loops in the prepontine cistern segment, 5 had a such corner alone and 9 had thickening arachnoid adhesion between artery and facial nerve but without compression or pushing/pulling of the nerve. The symptoms disappeared immediately after surgery in 92 patients, significantly relieved in 16, who were delay-cured after 3 months. The overall response rate was 100%. Conclusions Vascular compression of facial nerve REZ is a major cause of facial spasm. But vascular loops can directly push/pull prepontine cistern segment of facial nerve or indirectly pull facial nerve trunk through the arachnoid, which could also cause symptoms. Intraoperative identification of the offending vessel and intracranial segment decompression of the facial nerve are important factors for achieving surgical success.