METHODS: We retrospectively evaluated the records of 13 patients operated at the Cerrahpasa Medical Faculty Neurosurgery Clinic between 1991 and 2005 for vestibular schwannoma who had postoperative facial nerve palsy and in whom hypoglossal-facial nerve anastomosis was done. There were 9 female and 4 male patients with a mean age of 44.5 (Range 29-59) The preoperative facial nerve function of all patients was evaluated with the House-Brackmann (HB) grading for the facial nerve. Loss of integrity of CN VII was detected intraoperatively during the first operation for tumor resection by the operating surgeons in all cases and postoperatively all patients had complete facial palsies with HB grades of VI. All the patients were re-operated within 6 months following tumor resection. The mean time interval between the operations was found to be 2.2 months. The postoperative facial function was analysed at 3 months intervals by using HB grading.

RESULTS: In the majority of the cases ( 9 cases ) the first signs of reinnervation were detected between 3 and 6 months after surgery. The recovery HB grades were III in 7 patients, IV in 3 patients and V in 2 patients. In one patient, the operative result was a failure with a recovery HB grade of VI. Among all patients, eight had severe hemitongue atrophy and hemiglossal functional loss in the postoperative follow up period. In the remaining patients the hemitongue atrophy was found to be moderate.

CONCLUSION: Facial nerve reanimation should be performed in every patient suffering from facial nerve paralysis as a complication of VS surgery. Despite some of its disadvantages, the hypoglossal nerve transposition and end-to-end anastomosis directly to the facial nerve appears to be an effective and reliable technique with constant and satisfying results. Keywords : Facial nerve, Facial paralysis, Hypoglossal nerve, Nerve anastomosis, Vestibular schwannoma