A cavernous malformation, also called a cavernoma, is a cluster of abnormally dilated blood vessels that form a sponge-like lesion within the brain or spinal cord.
Unlike AVMs, cavernomas have slow blood flow and no direct connection between arteries and veins. However, their fragile vessel walls can leak or bleed over time, leading to neurological symptoms or seizures.
Modern imaging and microsurgical techniques now allow precise diagnosis and safe removal when necessary.
Symptoms
Cavernomas may remain silent for years or cause symptoms depending on their location and bleeding history.
Typical symptoms include:
- Seizures (most common presentation)
- Headaches or localized pressure pain
- Sudden weakness, numbness, or balance problems
- Speech or vision disturbances (if near eloquent brain areas)
- Repeated small hemorrhages, which can cause stepwise neurological decline
- In rare cases, acute intracerebral hemorrhage with severe headache or vomiting
Cavernomas in the brainstem or spinal cord tend to produce more noticeable deficits even after small bleeds.
Diagnosis
MRI with susceptibility-weighted or gradient-echo sequences is the best imaging method.
A cavernoma typically appears as a “popcorn-like” lesion with a mixed signal core (representing blood at different ages) surrounded by a dark rim of hemosiderin. CT scan may detect bleeding, but small lesions can be missed.
Digital subtraction angiography (DSA) usually appears normal, since cavernomas are low-flow lesions.
Treatment Options
1. Observation and MRI Surveillance
Small, asymptomatic cavernomas are often managed conservatively with regular MRI follow-up (typically every 6–12 months).
This approach is safe if there is no history of bleeding or seizure activity.
2. Microsurgical Removal
Surgery is recommended for cavernomas that cause repeated hemorrhage, drug-resistant epilepsy, or progressive neurological symptoms.
Using microsurgical and neuronavigation techniques, the lesion can often be completely removed with minimal damage to healthy brain tissue.
In epilepsy-related cases, resection of both the lesion and surrounding hemosiderin zone improves seizure control.
3. Radiosurgery
Stereotactic radiosurgery (Gamma Knife / CyberKnife) may be considered for deep or inoperable cavernomas, particularly in the brainstem.
It can reduce the risk of future bleeding, although the protective effect develops gradually over time.
Recovery & Follow-Up
Most patients recover within a few days after microsurgery.
Neurological symptoms from prior bleeding often improve with rehabilitation and physiotherapy.
Follow-up MRI scans are typically performed at 6 months and then annually to ensure no recurrence or new bleeding.
Patients with seizures usually continue antiepileptic medication for a period after surgery.