• Iris Zachenhofer, Stefan Wolfsberger, Martin Aichholzer, Alexander Bertalanffy, Karl Roessler, Klaus Kitz, and Engelbert Knosp.
• Department of Neurosurgery, Medical University of Vienna, Vienna, Austria. iris.zachenhofer@meduniwien.ac.at
• Neurosurgery. 2006 Jan 1; 58 (1): 28-36; discussion 28-36.

ObjectiveSurgical resection of cranial base meningiomas is often limited owing to involvement of crucial neural structures. Within the last 2 decades Gamma Knife radiosurgery (GKRS) has gained increasing importance as an adjunct treatment after incomplete resection and as an alternative treatment to open surgery. However, reports of long-term results are still sparse. We therefore performed this study to analyze the long-term results of GKRS treatment of cranial base meningiomas, following our previously published early follow-up experience.MethodsA retrospective analysis of the medical files for Gamma Knife and surgical treatments, clinicoradiological findings, and outcome was carried out focusing on tumor control, clinical course, and morbidity.ResultsBetween 1992 and 1995, we treated 36 patients with cranial base meningiomas using GKRS (male:female ratio, 1:5; mean age, 59 yr; range, 44-89 yr). Twenty-five patients were treated with GKRS after open surgery, and 11 patients received GKRS alone. Tumor control, neurological outcomes, and adverse effects were analyzed after a long-term follow-up period (mean, 103 mo; range, 70-133 mo) and compared with our previous results after an early follow-up period (mean, 48 mo; range, 36-76 mo). Control of tumor growth was achieved in 94% of patients. Compared with the early follow-up period, the late neuroradiological effects of GKRS on cranial base meningiomas were continuing tumor shrinkage in 11 patients (33%), stable tumor size in 20 patients (64%) and tumor progression in two meningiomas (6%). The neurological status improved in 16 patients (44%), remained stable in 19 patients (52%), and deteriorated in one patient (4%). Adverse side effects of GKRS were found only during the early follow-up period.ConclusionOur data confirm that GKRS is not only a safe and effective treatment modality for cranial base meningiomas in short-term observation, but also in a mean long-term follow-up period of more than 8 years. Tumor shrinkage and clinical improvement also continued during the longer follow-up period.

18 keywords...

hide…