Cavernous malformations are blood vessels in the brain or spinal cord which have formed abnormally. They take the form of a cluster of small blood vessels that looks a little like a blackcurrant or raspberry and vary in size from 2mm to many centimetres across. If they leak blood in the brain or spinal cord (i.e. haemorrhage) they can cause a range of problems. Generally known as 'cerebral cavernous malformations' (CCMs), they are also known by a number of different names, including 'cavernomas', 'cavernous angiomas', 'cavernous haemangiomas' and 'intercranial vascular malformations'. Occurrence in the general population is understood to be 0.5%-1%.
The precise reason why cavernous malformations occur is unknown - they can occur spontaneously without any obvious cause. In other cases, it may be an inherited condition, in which case genetic testing can determine if a person is likely to be prone to developing them. Around 1 in 5 cases are inherited conditions. Having radiation treatment to the brain is also considered a risk factor.
Most people with CCMs do not have any symptoms at all. Where they do occur, symptoms are very similar indeed to those for brain arteriovenous malformations. Common symptoms include headaches, stroke-like symptoms and seizures. Diagnosis often follows a scan for another issue which reveals the presence of a CCM. Recurrent bleeding episodes from a CCM can cause a range of neurological symptoms, and repeated seizures that worsen over time can also be caused by CCM. Around 1 in 3 people with a cavernous malformation will develop symptoms and these generally appear when people are aged in their twenties or thirties.
Tests / Diagnosis
Standard test required to diagnose cavernous malformations include…
- MRI (magnetic resonance imaging) scan.
- MRI angiography or venography may help more accurately identify the condition by injecting dye into the blood vessels (normally via a vein in the arm).
- Digital Subtraction Angiogram (DSA) or Cerebral angiogram – CCMs generally are invisible on DSA, but this is performed to exclude other conditions such as brain AVMs.
- Genetic testing (three genetic variants have been determined to account for the vast majority of inherited cases).
Treatment for CCMs usually involves observation and controlling seizure symptoms with medications. If repeated bleeding episodes occur causing progressive brain damage, or repeated seizures are beyond medication control, CCMs can be removed with microsurgery. Craniotomy – Basic Facts