Facial Nerve Preservation In Vestibular Schwannoma Surgery- Anatomical And Functional Status

Abstract

IntroductionSurgery for vestibular schwannoma taxes the surgeon’s skill to the hilt especially in removing the tumor completely and preserving the facial nerve.Aims To study the anatomical and functional status of the facial nerve in patients after vestibular schwannoma surgery and analyze the factors contributing to the outcome after surgery.Materials and methodsA retrospective analysis of all the case records of patients operated for Vestibular Schwannoma from 1980 to December 2007 in Kasturba Hospital Manipal was done which included their pre operative facial nerve function and post operative anatomical and functional status. The data was analyzed and conclusions drawn.Results210 patients who underwent surgery for vestibular schwannoma were included. In 111 patients(53%) preoperative facial nerve deficit was present and graded by House and Brackman grading. 207 out of 210 patients were operated by suboccipital retromastoid route. In 138 patients anatomical preservation of facial nerve was done, of which 120 patients underwent internal auditory meatus drilling. The rate of anatomical preservation has increased from 10% in the initial part of the study period to 100% in the latter part. Overall, 82.8% of the patients had a good functional outcome and 17.2% had a worse functional state than their preoperative status. We had operative mortality of 2.5%ConclusionsAbility to preserve the facial nerve improves with number of cases. Transmeatal drilling helped in identifying and protecting the facial nerve. Majority of patients in our series have presented as large tumors (69%) inspite of which good functional outcome was achieved.