Cerebrovascular Malformations (CVM): Overview

What are cerebrovascular malformations?

Cerebrovascular malformations (CVMs) are abnormally formed blood vessels in and around the brain and spinal cord.  They may be harmless, but some cause neurological problems because of their size and location, or due to seizures or bleeding.

There are four types of CVM:

  • Arteriovenousmalformations (AVMs) are tangles of abnormal blood vessels.
  • Cavernous hemangiomas (also called cavernomas and cavernous malformations) are clusters of very wide, thin-walled blood vessels.
  • Developmental venous anomalies (DVAs) are abnormally large veins.
  • Aneurysms are weak areas in the walls of arteries that balloon and bulge because of the weakness. 

What causes cerebrovascular malformations? 

No one knows for sure what causes malformations.  Most AVMs, cavernomas, and DVAs probably result from abnormal development of the blood vessels while the brain is growing.  Most aneurysms and some cavernomas probably develop after the brain is already grown.

Who gets cerebrovascular malformations? 

AVMs and DVAs can occur in anyone.

Cavernomas often run in families, especially families withHispanic heritage; however, they also occur when no one else in the family has hada cavernoma. 

Aneurysms occur more often in adults, especially in those who smoke and have high blood pressure, but occasionally they occur in children.

Helpful resources

Children's Hospital Colorado Stroke Program