Infographic: Lurking danger: Abnormal blood vessels in the brain

Lurking danger: Abnormal blood vessels in the brain

Brain vascular malformations are rare but potentially serious conditions.

  • Blood vessels are tangled, misshapen or misrouted.
  • Risk of bleeding (hemorrhage), which can lead to mild symptoms or can result in severe disability or even death.
  • Often there are no symptoms until bleeding occurs. May be discovered during a scan performed for other conditions or after serious symptoms related to the vascular malformation have occurred, such as seizure, weakness or change in vision.

Healthy blood vessels deliver blood throughout the brain.

Normal vascular structure

  • Artery
  • Vein
  • Capillaries
  • Oxygenated blood (red) travels in arteries to a network of blood vessels and capillaries.
  • Oxygen and nutrients are delivered to tissue while the blood is in the capillaries.
  • Oxygen-depleted blood (blue) exits the vessels to a vein, which returns it to the heart.

A vascular malformation alters the blood vessels.

Brain arteriovenous malformation

  • Vessels are tangled, enlarged and weakened.
  • Symptoms may appear in youth or early childhood.

Cavernous malformation

  • One or several areas of mulberry-shaped abnormal blood vessels
  • May be hereditary

Dural arteriovenous fistula

  • Blood vessels are connected incorrectly, with arterial blood from within the covering of the brain (dura) routed directly into veins.
  • Often acquired later in life.

Know the signs.

  • Seizures
  • Weakness or numbness in one part of the body
  • Confusion, difficulty speaking or understanding
  • Vision problems
  • Pulsing noise in the ears (for some types of malformations)
  • Headaches, especially localized

Early treatment is key to success.


  • Remove the malformation.
  • Reroute or repair blood vessels.


  • Block or reduce blood flow to the malformation.
  • Uses minimally invasive surgery to deliver an embolizing agent (particles or glue-like substance).

Stereotactic radiosurgery

  • Also known as Gamma Knife surgery
  • Uses focused, high-power radiation to destroy a malformation without a surgical incision

Conservative treatment

  • Some brain vascular malformations can be safely left alone, and intermittent repeat imaging may be recommended.