title: Stereotactic radiosurgery of skull base meningiomas.
abstract: Between April 1992 and March 1994, 48 patients with skull base meningiomas were treated at our department. The age of these patients ranged from 10 to 76 years. The male:female ratio was 1:3. Thirty-seven of these patients had primary open surgery for partial removal and subsequent radiosurgical treatment. In 1 patient a recurrent meningioma after so-called total microsurgical removal was treated radiosurgically. Radiosurgery was performed as a primary treatment in 11 patients. The mean tumor volume was 13.7 cm3 (range: 0.8-82 cm3). These tumor volumes could be covered by mean isodose volumes of 44% (range: 30-70%) and were treated by a mean dose of 15 Gy (range: 8-25 Gy) at the tumor border. One patient underwent radiosurgery with a staged treatment protocol with a 4.6-month interval. In 37 patients, a total of 102 follow-up scans were available. The remaining 11 patients have not been included in the postradiosurgical evaluation, since the observation time was either too short or the patients were lost to follow-up. The mean interval between Gamma Knife treatment and the last follow-up scan was 12 months, with a range from 2.3 to 22.7 months. Follow-up imaging (CT, MRI or both) revealed a decreased volume of the tumor in 9 cases (24%). In 25 cases (68%), tumor progression was stopped, and in 3 cases (8%) increased tumor volumes could be observed (2 patients with malignant meningiomas). In 3 cases marked central tumor necrosis was seen. Neurological follow-up examinations (n = 38 patients) showed a stable neurological status in 74%, ameliorated status in 13% and worsening in 13% of the patients.
authors.affiliation: Department of Neurosurgery, University Medical School, Graz, Austria.
authors.forename: G
authors.initials: G
authors.lastname: Pendl
authors.forename: O
authors.initials: O
authors.lastname: Schröttner
authors.forename: G M
authors.initials: GM
authors.lastname: Friehs
authors.forename: H
authors.initials: H
authors.lastname: Feichtinger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008579:Meningioma / Q000000981:diagnostic imaging / Q000601:surgery*; D008875:Middle Aged; D016634:Radiosurgery / Q000379:methods*; D012189:Retrospective Studies; D012888:Skull Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome