PRESERVATION OF CRANIAL NERVE FUNCTION AFTER RADIOSURGERY FOR NONACOUSTIC SCHWANNOMAS

MICROSURGICAL RESECTION IS the primary management approach for patient s with intracranial schwannomas. Recent studies have demonstrated that stereotactic radiosurgery is an effective therapeutic modality for pa tients with acoustic schwannomas. To define the role of radiosurgery i n the management of patients with nonacoustic schwannomas, we reviewed the results of gamma unit stereotactic radiosurgery in six patients w ith trigeminal and five patients with jugular foramen region schwannom as. No patient with a trigeminal schwannoma demonstrated tumor growth during a mean follow-up of 21 months (range, 7-35 mo), whereas one pat ient with a jugular foramen region schwannoma had an increase in tumor size 7 months after radiosurgery. No new cranial nerve or brain stem deficits were noted in either patient group after radiosurgery. In thi s early experience, radiosurgery proved an effective primary or adjuva nt technique for selected patients with schwannomas of the trigeminal, glossopharyngeal, or vagus nerves. Using our described method, the sa fety of radiosurgery was demonstrated on the brain stem, regional cran ial nerves, and especially those cranial nerves intimately associated with the tumour.