Radiosurgery of Benign Lesions

The use of stereotactic radiosurgery is increasing at an accelerated rate throughout the United States and the rest of the world. The greatest success for radiosurgery has been in the treatment of benign intracranial mass lesions and arteriovenous malformations (AVM) in particular. The majority of large radiosurgery series report that AVM obliteration rates exceed 74% and serious complication rates (permanent brain injury) exceed less than 5%. Radiosurgery is being investigated as a treatment for high-risk angiographically occult vascular malformations (cavernous angiomas) with a history of hemorrhages, but is contraindicated in asymptomatic patients. Radiosurgery has been successfully established as an alternative to surgical resection of vestibular schwannomas (acoustic neuromas). Long-term tumor control rates with radiosurgery are above 85%. Radiosurgery offers tumor control comparable to surgery with better preservation of hearing and facial nerve function. Radiosurgery has also been found to be equally effective in controlling nonacoustic schwannomas and meningiomas. Radiosurgery offers the potential of faster and higher response rates in treating functional pituitary adenomas than fractionated radiotherapy with a greater chance of preserving normal pituitary function. Long-term studies with 10 to 15-year follow-up are still needed to fully compare the efficacy of radiosurgery with other modern techniques for treating pituitary adenomas and meningiomas (such as cranial base microsurgery and fractionated large-field radiotherapy). Overall, radiosurgery is a relatively safe and effective alternative to surgical resection of small AVMs and most benign intracranial tumors.