Jugular Foramen Schwannomas

ABSTRACT

The cases of ten patients with schwannomas of the jugular foramen who underwent surgery in our department between 1983 and 1996 are described. Seven were women and three were men(mean age 40 years) and the duration of their symptoms, the most predominant of which were hearing loss and tinnitus, ranged from 1 months to 20 years(median 8.5 months). Computerized tomography was performed in all cases, magnetic resonance imaging in eight, and angiography in three. Depending on their radiological and surgical features, the tumors were classified as follows Type A, a tumor primarily at the cerebellopontine angle, with minimal enlargement of the jugular foramen(n=5) ; Type B, a tumor primarily at the jugular foramen, with or without intracranial extension(n=4) ; Type C, a primarily extracranial tumor with extension into the jugular foramen(n=0) ; Type D, a dumbbell-shaped tumor with both intra- and extracranial components(n=1). A retromastoid suboccipital craniectomy(RM-SOC) was performed for type A tumors, and the RM-SOC or staged infratemporal fossa approach/RM-SOC was used for type B and D. Total removal was achieved in six cases, and no patient died. Postoperative complications were detected in six cases, with low cranial nerve dysfunction most common(n=5). The follow-up period ranged from 14 to 173(mean 48) months. In one patient, a subtotally-resected tumor recurred ; this was again resected and LINAC radiosurgery was successful. In the remaining nine patients, tumors did not recur. It is suggested that jugular foramen schwannomas could be totally resected by RMSOC/ITFA ; to reduce postoperative complications, cases showing adhesion to critical structures could be managed with sub- or near-total resection.