Brain Aneurysm

A brain aneurysm is a weak or thin spot on a blood vessel in the brain that balloons and fills with blood. It is usually located along main arteries on the underside of the brain and the base of the skull.

Brain aneurysms may rupture and bleed, causing serious complications like stroke, coma and death. After an initial rupture, brain aneurysms may rupture and bleed again.

Complications arising from a rupture could include:

Hydrocephalus
Blood from a ruptured brain aneurysm blocks the fluid circulation in the brain. This causes an excessive build-up of fluid within the brain cavity (ventricles) and increases brain pressure. A temporary external drain may be inserted to relieve the brain pressure and permanent shunt (catheter) may be needed if it cannot be removed.

Cerebral Vasospasm
About a week after the rupture, blood vessels in the brain may contract spontaneously and limit blood flow to other areas of the brain, resulting in a stroke (Figure 1).

To prevent vasospasm, a drug called Nimodipine is usually given orally or through the veins for 21 days or lesser. The patient is also kept well-hydrated and the blood pressure slightly higher.

In certain cases, Nimodipine can also be given directly to the cerebral arteries via the endovascular method to relieve vasospasm.

Figure 1
Normal and constricted blood vessel

Brain Swelling
Brain swelling increases pressure in the skull and prevents blood flow to the brain. Further surgery may be needed to remove parts of the skull to release pressure.

Seizure
Brain injury following a rupture results in the formation of scar tissue. This may cause a seizure. A seizure is a sudden, uncontrolled electrical disturbance in the brain leading to changes in behaviour, movements, feelings and consciousness. Medication to prevent or control seizures may be needed.