Introduction: Meningiomas are common intracranial benign tumors that can be surgically excised. However, their intimate involvement with critical neurovascular structures often prevent their complete resection. Gamma Knife radiosurgery is a minimally invasive option which provides excellent tumor control as both an adjunct and primary therapy.
Materials and methods: Between September 1987 and December 2004, 964 patients underwent Gamma Knife radiosurgery at the University of Pittsburgh for the diagnosis of meningioma. The majority of patients had tumors located at the skull base. All imaging and clinical follow-up was reviewed.
Results: Overall, Gamma Knife radiosurgery provides 5- and 10-year actuarial tumor control rates of 93% for benign meningiomas. The 5-year actuarial control rate for patients with atypical and malignant meningiomas was 83 +/- 7 and 72 +/- 10%, respectively. The incidence of adverse radiation effect ranged from 5.7 to 16%; however, the incidence was gradually reduced with the advent of magnetic resonance imaging and lower dosing since 1991.
Conclusion: Gamma Knife radiosurgery is an attractive option for patients with intracranial meningiomas. It can be used as both primary treatment based on imaging diagnosis alone, or as an adjunct treatment after craniotomy. It provides long-term tumor control with minimal adverse sequelae.