Cavernous Malformation
A cavernous malformation, also called a cavernoma or cavernous angioma, is a cluster of abnormal thin-walled blood vessels located in the brain or spinal cord. These blood vessels form small, mulberry-like collections that may leak small amounts of blood over time. Many cavernous malformations cause no symptoms and are discovered incidentally on imaging, while others may lead to seizures, headaches, neurological symptoms, or bleeding depending on their size and location.
What is it?
Cavernous malformations develop when small blood vessels form abnormal clusters of dilated, thin-walled vascular channels that may slowly leak blood. On MRI, these lesions often have a characteristic “popcorn” or “mulberry” appearance due to blood products at different stages of breakdown.
Cavernous malformations may occur anywhere within the central nervous system, including the cerebral hemispheres, brainstem, cerebellum, and spinal cord. Most occur sporadically, although inherited forms can cause multiple lesions throughout the brain and spine.
MRI is the preferred imaging test for evaluating cavernous malformations because it provides detailed visualization of the lesion and surrounding blood breakdown products. Specialized MRI techniques such as susceptibility-weighted imaging (SWI) are especially sensitive for detecting very small lesions or additional cavernomas that may not be apparent on standard MRI sequences.
CT imaging may detect bleeding associated with a cavernous malformation, but smaller lesions are often difficult to visualize. Conventional angiography is typically less useful because these malformations have very slow blood flow and may not be visible on angiographic studies.
Important to Know
Many cavernous malformations remain stable for years and never cause symptoms, particularly when they are small or located away from critical neurological structures. When symptoms occur, they may result from bleeding, irritation of nearby brain tissue, or pressure on surrounding structures.
Treatment depends on lesion location, symptoms, and bleeding history. Some patients are monitored with periodic MRI imaging, while others may require medication for seizure control or surgical treatment in selected cases. Stereotactic radiosurgery may occasionally be considered for lesions that are difficult to access surgically.
Follow-up MRI is commonly recommended to monitor for growth, interval bleeding, or new lesions over time.
Red flag symptoms include sudden severe headache, new or worsening weakness, seizures, difficulty speaking, vision changes, or loss of consciousness. These symptoms may indicate bleeding and require immediate medical evaluation.