Cerebral cavernous malformation (CCM) is a collection of small blood vessels in the central nervous system that are enlarged and irregular in structure. CCMs are also known as cerebral cavernous angiomas or cavernomas. They can occur in the brain, spinal cord, or other parts of the body, and are filled with slow-moving or clotted blood. CCMs can cause a wide range of neurological symptoms, including seizures, severe headaches, weakness in the arms or legs, numbness, difficulty speaking, problems with memory and attention, problems with balance and walking, vision changes, and paralysis. CCMs are rare, with an incidence in the general population of roughly 0.5%, and clinical symptoms typically appear between 20 and 30 years of age.

Most CCMs occur as a single formation or lesion, with no specific cause, and may be present at birth or develop later in life. However, approximately 25% of those diagnosed with CCM have the hereditary form of the condition, which is often associated with multiple blood vessel formations. The inherited form of CCM is caused by mutations in one of three CCM genes: CCM1, CCM2, and CCM3. These genes produce proteins that are found in the junctions connecting neighboring blood vessel cells, and the proteins interact with each other as part of a complex that strengthens the interactions between cells and limits leakage from the blood vessels.

Diagnosis of CCMs is typically done via MRI when an individual becomes symptomatic, and for some patients with high-risk lesions, regular MRIs are recommended to assess changes in size, recent bleeding, or the appearance of new lesions. Treatment of symptomatic CCM is only via surgery, depending on the location of the lesions, and there are no pharmaceuticals currently available to treat CCM.