The Effect of Gamma Knife in the Size and Rate of Bleeding in Cavernous Malformation

Abstract

Background: Cerebral cavernous malformations (CCMs) are vascular lesions that may cause recurrent intracranial hemorrhage and neurological deficits. Gamma Knife radiosurgery (GKRS) is a minimally invasive treatment option for lesions located in deep or eloquent brain regions where microsurgical resection is associated with substantial risk.

Aim: To evaluate the effect of GKRS on lesion size, hemorrhage rate, safety, and clinical outcomes in patients with cerebral cavernous malformations.

Patients and Methods: This retrospective, single-center, longitudinal study included 20 patients with CCMs who underwent GKRS at the Department of Neurosurgery, Faculty of Medicine, Al-Azhar University, Damietta. Clinical, radiological, and treatment-related data were reviewed from the time of GKRS until the last follow-up. Radiological response, hemorrhage rate, clinical outcome, seizure control, and treatment-related adverse effects were assessed.

Results: Effective volumetric control (≥20% reduction) was achieved in 75% of patients. The recurrent hemorrhage rate decreased from 16.33 to 3.72 events per 100 patient-years, representing a 77.2% relative reduction (p=0.069). Clinical improvement or stabilization occurred in 90% of patients, while favorable seizure control (Engel class I–II) was achieved in 87.5% of patients with seizures. Symptomatic adverse radiation effects occurred in 10% of patients without persistent neurological deficits. Brainstem lesions showed significantly poorer volumetric control and higher post-treatment hemorrhage rates than non-brainstem lesions.

Conclusion: GKRS is a safe and effective treatment for selected patients with cerebral cavernous malformations, providing significant long-term lesion volume reduction, decreased hemorrhage risk, and favorable clinical outcomes, particularly for surgically challenging lesions.