A cavernoma is an abnormal group of blood vessels in the brain, brain covering, spinal cord or nerves of the brain, according to the American Association of Neurological Surgeons. A cavernoma contains a cluster of many small blood vessels and larger blood vessels with abnormally thin walls.
Cavernomas are typically between 1/4 inch and 4 inches wide, notes the American Association of Neurological Surgeons. In some cases, they grow over time. They cause problems when the blood vessels leak blood. Possible symptoms include seizures, limb weakness, vision and balance problems, and headaches. Treatment options, which vary depending on the severity of symptoms and the exact location of the cavernoma, include medications and surgical interventions.