Vestibular schwannoma microsurgery for recurrent tumors after radiation therapy or previous surgical resection.

Objective: The purpose of this study is to compare the outcomes in patients who underwent microsurgical resection for recurrent vestibular schwannoma after microsurgical resection and previous radiation therapy. Study Design: Retrospective study. Setting: University hospital. Patients: Fifteen patients, who underwent microsurgical resection for recurrent vestibular schwannoma after previous surgery (group A), and 5 patients, who underwent microsurgical resection after previous radiation therapy (group B) were included. Intervention: Surgical resection after radiation therapy or previous surgical resection. Main Outcome Measures: Intraoperative findings and postoperative facial nerve function were investigated in groups A and B. Results: Mean tumor volumes were 18.4 +/- 2.44 cm(3) in group A and 19.0 +/- 1.53 cm(3) in group B. Total resection was achieved in 10 patients (67%) of group A and in 3 patients (60.0%) of group B. The tumor was more difficult to resect because of severe adhesions to the facial nerve. Anatomic facial nerve preservation could be achieved in 19 patients. Mean follow-up time was 80 months for group A and 28 months for group B. At last follow-up, 7 patients (53.8%) of group A had a good facial nerve function. In 3 patients (75.0%) of group B, the preoperative facial nerve function was preserved postoperatively. Preexistent facial paresis, large tumor with extrameatal growth and brainstem compression correlated with poor postoperative facial nerve function. Conclusion: Surgical outcome of recurrent vestibular schwannoma is more unsatisfactory than after primary surgery. It remains to be clarified whether previous surgery may implicate a higher risk for postoperative facial nerve function than previous radiation therapy upon surgery for tumor recurrence.