A cavernous malformation or cavernoma is a vascular abnormality characterised by a cluster of abnormally dilated minute blood vessels with thin walls that occasionally rupture and cause blood leakage into surrounding tissues. Cavernomas usually develop in the brain, but may also be seen in the spinal cord, retina of the eye and skin. They may be caused by genetic factors. Cavernomas are dynamic structures that can increase in size from millimetres to centimetres.

It is common for cavernous malformations to not produce any symptoms and to be detected incidentally. Symptoms may occur however depending on their location in the brain and strength of the vessel walls, and may include headaches, seizures, limb weakness, vision abnormalities, and attention, memory and balance deficits. Symptoms may come and go as the cavernoma changes in size.

To diagnose a cavernous malformation your doctor will review your symptoms, perform a physical examination, and order imaging studies such as MRI or CT scans to confirm the diagnosis.

If a cavernous malformation is asymptomatic, your doctor will monitor it with periodic MRI scans. Symptoms of cavernous malformations are usually controlled with medication. Microsurgical resection is suggested when symptoms are progressive, cannot be controlled otherwise, and when the cavernous malformations are easily accessible and can be safely removed without significant damage to brain tissue.