Cavernous malformations are well demarcated mulberry-like lesions composed of thin-walled sinusoidal channels. Thanks to introduction of magnetic resonance imaging (MRI), vascular malformations are being diagnosed with increasing frequency. Cavernous malformations constitute about 10% of all cerebrovascular malformations and are present in about 0.5% of the population. There is no sex predominance, with the highest incidence occuring in fourth decade. The most common symptom is seizure, followed by focal neurological deficits, headache and hemorrhage. The annualized bleeding rate is 0.7%, with the significantly greater risk of overt hemorrhage in females. The lesion is asymptomatic in about 16% of patients. Cavernous malformations usually are sporadic but multiple lesions are common in the familial form (50% to 73%). Symptom presentation is strongly related to the size of lesion greater than 1 cm in diameter.