Cavernous malformations occur in 0.3-0.5% of the population and in 1/200 people between the ages of 30-50. Pathologically, a cavernoma contains vascular channels without the typical architecture of normal blood vessels. Headache, bleeding and seizures are the most common presenting events although a proportion of lesions are discovered incidentally. Hemorrhage rates range from 0.5% to 6% annually; bleeeding rates are higher in brainstem cavernomas or in those that had bled previously. Apart from surveillance of asymptomatic lesions, treatment is limited to surgery and is indicated in patients with hemorrhagic lesions, in those with intractable seizures or who have suffered from a neurological disability.

The video below illustrates techniques necessary to safely remove a cavernous malformation deep to the primary motor cortex.