Gamma knife radiosurgery of brain cavernomas

Area of Science:

• Neurosurgery
• Radiation Oncology
• Neurology

Background:

• Cavernomas (cerebral cavernous malformations) pose risks of rebleeding, growth, and neurological decline.
• Current methods for assessing radiosurgery effectiveness rely on clinical observation and MRI over extended follow-up periods.
• Lack of direct diagnostic tools necessitates robust outcome analysis for radiosurgery in cavernoma treatment.

Purpose of the Study:

• To evaluate the efficacy and safety of Gamma Knife radiosurgery for treating brain cavernomas.
• To assess the impact of radiosurgery on rebleeding rates, lesion size, and clinical symptoms.
• To determine the long-term outcomes and risks associated with radiosurgery for cavernomas.

Main Methods:

• A cohort of 112 patients with brain cavernomas underwent Gamma Knife radiosurgery between 1992 and 2000.
• Patients were stratified based on prior bleeding history (59 with, 53 without).
• Median patient age was 42 years, median cavernoma volume 0.9 cm³, and median marginal dose 16 Gy, with a median follow-up of 84 months.

Main Results:

• Following a 2-year latent period, the annual rebleeding risk decreased from 3.7% to 0.2% in previously bleeding cavernomas.
• The annual rebleeding risk for non-bleeding cavernomas was 0.8%.
• Cavernoma size reduction occurred in 53.0% of cases; epilepsy symptoms improved in 45% of affected patients. Temporary and permanent morbidity rates were 14.6% and 0.9%, respectively.

Conclusions:

• Gamma Knife radiosurgery demonstrates a low risk of permanent morbidity for brain cavernoma treatment.
• The study confirmed a significant reduction in rebleeding risk after a 2-year post-treatment interval.
• Radiosurgery for cavernomas without a history of bleeding was discontinued due to observed outcomes.