Cerebrovascular Neurosurgery - Cavernous Malformation
Also known as:  Cavernoma / Agiographically occult vascular malformation / Cavernous angioma

What is a cavernous angioma?

A cavernous angioma is a vascular (blood vessel) abnormality, characterized by the presence of large, sinusoid-like capillary vessels. These capillaries are adjacent to one another, with little or no intervening brain. The blood-flow through these vessels is slow.

Where do these lesions occur?

Cavernous angiomas can occur anywhere in the central nervous system. Multiple lesions are common.

How common are cavernous angiomas?

The incidence of these lesions is 0.15 percent of the population. Up to 50% of these patients have multiple lesions.

What are the symptoms of cavernous angiomas?

Symptomatic lesions can present with seizures, headache, hemorrhage, or mass effect (compression of surrounding brain). Mass effect can cause focal neurological signs, such as weakness, numbness, double vision, visual disturbance, or language difficulties. A large number of cavernomas are not symptomatic and are found incidentally.

How are cavernous angiomas diagnosed?

Magnetic resonance imaging (MRI) is the most sensitive test to identify these lesions, which are represented as well-defined and usually rounded lesions. MRI scans often show small areas of new or old hemorrhages as a rim around the cavernous angioma. Cavernous angioma lesions are not seen on cerebral angiography.

What is the risk of hemorrhage?

The annual risk of symptomatic hemorrhage is between 0 and 10 percent, depending on the location of the cavrnous angioma. Cavernomas in the cerebral hemispheres have very low symptomatic hemorrhage rates. Cavernomas in the brain stem have symptomatic hemorrhage rates approaching 10 percent per year.

How are cavernous angiomas treated?

The optimal treatment option for symptomatic lesions is surgical removal. Before a decision is made on operative treatment, the risks of hemorrhage, age of the patient, presence of previous hemorrhages, and symptoms need to be weighed along with the risks of surgery. The consequences of a hemorrhage from a cavernous angioma are rarely catastrophic, in contrast to AVMs or aneurysms. Patients who present with seizures may have their seizures controlled medically. If seizures are persistent or the patient suffers side effects of the anti-seizure medication, surgery may be considered for relief of the seizures.

Radiosurgery (gamma knife surgery or GKS) is neither accepted nor recommended as a treatment option for cavernous malformations. Despite the lack of evidence to support its use, however, GKS is considered in cases where lesions repeatedly hemorrhage but are not surgically resectable.