Endoscopic microvascular decompression of the hemifacial spasm

BackgroundWe performed endoscope-assisted MVD or fully endoscopic MVD for minimizing the risks of brain retraction and extensive dissection and got good results. In addition, we highlighted the value of endoscopy in the diagnosis and therapy for cranial nerve pathologic condition in the posterior fossa.MethodsAmong 300 consecutive patients with microsurgically treated HFS, 32 patients underwent endoscope-assisted MVD or fully endoscopic MVD through the retromastoid approach between July 1998 and December 2002, at the Department of Neurosurgery, Taichung Veterans General Hospital, Taichung, Taiwan, ROC. The use of endoscopes is indicated for patients who had difficulty in identifying the nerve-vessel conflicts.ResultsThe procedure was successful in 96.9% of patients and improved in 3.1%. No failure or recurrence was noted. The postoperative complications were found in 2 patients who were treated by endoscope-assisted MVD. One patient (3.1%) showed delayed facial palsy on the seventh day but was fully recovered 2 months later. Hearing impairment was noticed in one patient (3.1%). There was no perioperative mortality.ConclusionFrom our experience, we conclude that the endoscope's superior visualization more accurately identifies neurovascular conflicts and provides a comprehensive evaluation of the completeness of the decompression. In addition, this method minimizes the risks of brain retraction and extensive dissection often required for microscopic exposure. Endoscopes are good as an adjunctive imaging modality to confirm nerve-vessel conflicts identified by the microscope and to reveal others that escaped from microscopic survey.