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Cerebral (Brain) Aneurysms


What is a cerebral aneurysm?

A cerebral aneurysm is a bulge or balloon like dilatation/swelling of the wall of a blood vessel in the brain. It is a weakening in the wall with a propencity to rupture.


Types of aneurysms?

Aneurysms develop because of a weakness in the wall of the vessel, usually at branch points. The cause of most aneurysms is unknown. In a small number of patients, aneurysms are inherited with multiple family members affected. Aneurysms can be grouped into the following categories:

  1. Berry or Saccular
  2. Dissecting
  3. Fusiform



Why Aneurysms Develop?

We do not know why aneurysms develop in a majority of cases, however the following may play a role:

  • familial/hereditary
  • vessel wall disorders
  • post infection
  • post trauma


Who gets aneurysms?


  • Peak incidence is between 40-60 years old.
  • Very rare in children.
  • Female predominance in adults


How do I know that I have one?

Most patients who have aneurysms have no symptoms.

Sometimes aneurysms can causes pressure symptoms (like double vision, seizures, numbness). Such incidence in the general population is 5/100,000 persons per year.

If you have two first-degree relatives with cerebral aneurysms, your risk of harboring an aneurysm is four times the general population.

Most aneurysms present with hemorrhage which results in a sudden severe headache or unconsciousness. Aneurysm hemorrhage may result in death.


Who are at risk of a rupture of an aneurysm?

Asymptomatic aneurysms which are larger than 6 mm are more prone to rupture.

There are a few factors which are clearly associated with an increased risk of rupture:

  • Females
  • Hypertension
  • Smoking

NOTE: Pregnancy doesn't increase the risk of rupture.


How are AVMs Diagnosed?

There are few tests which are used in detecting aneurysms:

Computerized Tomography (CT scan): uses X-rays to image different parts of the body. CT scanning is an excellent method of detecting bleeding into the brain or the fluid spaces around the brain. The study of the brain may be done either without or with dye. On the CT scan it may be possible to see an evidence of hemorrhage associated with a brain aneurysm.


CT Angiography: is a noninvasive way of seeing brain blood vessels but often does not give well defined images with which to plan treatment.

Magnetic resonance imaging (MRI) : is a method of producing highly detailed images of the body without the need for x-rays. MR angiography (MRA) utilizes "pulse sequences" specifically designed to show the arteries and veins of the brain as well as the aneurysm. MRI examination shows in detail the aneurysm and it relationship to the brain.



Carotid & Vertebral digital substraction angiography: is the definitive method to detect aneurysms. Using a groin artery, a catheter is placed in the blood vessels leading to the brain and a contrast agent or dye is injected to photograph the blood vessels.


What treatment Choices are there?

Aneurysms are managed in following ways :

  1. No treatment : asymptomatic aneurysms less than 5 mm may require no treatment. A periodic screening may be recommended to check for any enlargement in size.
  2. Endovascular treatment : through the artery in the groin, a platinum coil is introduced into the aneurysm to occlude it.
  3. Surgery : aneurysms are clipped at their neck with clips.