cavernous malformation
Vascular anomaly consisting of enlarged capillary spaces without normal brain tissue, showing characteristic popcorn appearance.
Full Definition
Cavernous malformations, also known as cavernomas or cavernous hemangiomas, are low-flow vascular anomalies composed of enlarged, thin-walled capillary spaces lined by endothelium without intervening normal brain tissue. On MRI, they classically demonstrate a 'popcorn' appearance with a reticulated core of mixed signal intensity surrounded by a hemosiderin rim appearing dark on gradient echo sequences. These lesions have a propensity to bleed, causing seizures, focal neurological deficits, or headaches. They can be sporadic or familial, with multiple lesions suggesting a genetic etiology. Unlike arteriovenous malformations, they do not show flow voids on conventional MRI.
Usage
Usage note: Specify presence of hemosiderin rim and absence of flow voids.
In Context
- "A 2cm cavernous malformation was identified in the left temporal lobe with surrounding hemosiderin." — MRI report
- "Multiple cavernous malformations suggested familial cavernomatosis." — Genetic counseling report