Comparison of facial nerve function results after translabyrinthine and retrosigmoid approach in medium-sized tumors

Objective: To compare postoperative facial nerve function results according to surgical approach. Study Design: Retrospective case review study, Setting: All surgical procedures were conducted in collaboration with a neurosurgery team in teaching hospitals with an academic affiliation. Patients: Patients with medium to large vestibular schwannomas, with the tumor size ranging from 2 to 3 cm. Ninety-eight patients were identified from an Acoustic Neuroma. Database (date range of search, 1983-2000). Main Outcome Measures: The House-Brackmann scale was used for grading facial function in the immediate postoperative period and 1 year after. Guidelines of the American Academy of Otolaryngology-Head and Neck Surgery were used for classification of hearing preservation. Results: Of the 98 patients, 17 were operated on through a retrosigmoid approach and 81 through the translabyrinthine route. The mean +/- SD ages of these 2 groups of patients were 46 +/- 13 and 51 +/- 14 years, respectively; mean SD tumor sizes were 2.5 +/- 0.27 and 2.6 +/- 0.28 cm, respectively. One year after tumor removal via retrosigmoid approach, 10 (59%) of the 17 patients had good (grade I-II) facial functions and 2 (12%) had poor (grade V-VI) function. In the translabyrinthine group, 54 (68%) of 79 patients (2 patients had subtotal total tumor removal) had good facial nerve function at the end of the 1-year follow-up, and 13 (17%) continued to have poor facial function. The difference between these groups was not statistically significant (P>.05). Hearing was preserved in 4 (24%) of the 17 patients in the retrosigmoid group. Conclusion: Although the translabyrinthine approach may offer better long-term facial function compared with the retrosigmoid approach in patients with medium-sized tumors, the difference between these 2 groups was not significant enough to favor one approach over the other.