Brain Aneurysm - Diagnosis & Treatment

How is a brain aneurysm diagnosed?

Brain aneurysms often remain undetected until they are picked up during tests for other conditions.

If you experience symptoms related to a ruptured brain aneurysm, your doctor may recommend imaging tests to diagnose and locate the bleeding. These include:

• Angiogram, a type of X-ray used to find blockages in arteries and identify weak spots in the vessel walls. This is the most common diagnostic test for brain aneurysms.
• Computerised tomography (CT) scan and angiogram uses specialised X-rays to produce 2D images of the brain and skull. It is helpful in locating the aneurysm and seeing if blood has leaked into the brain.
• Magnetic resonance imaging (MRI) produces detailed images of the brain using radio waves and a magnetic field. It can help to identify the size, location and extent of the bleeding.
• Cerebrospinal fluid (CSF) analysis may be recommended if your symptoms strongly suggest you have a ruptured aneurysm, but the CT scan comes back negative. Your doctor will carry out a lumbar puncture to extract a sample of CSF from your spine and analyse it for signs of bleeding.

Screening is rarely done for brain aneurysms. It is only recommended for people at high risk of developing a brain aneurysm due to family history or certain medical conditions.

How is a brain aneurysm treated?

For small unruptured brain aneurysms, you may have to undergo a period of active observation. Your doctor will conduct a risk assessment and discuss with you to see if the benefits of treatment outweigh the potential risks.

However, if the aneurysm has ruptured, or is at high risk of rupturing, it must be treated immediately to avoid potential death. The aim of treatment in this case would be to stop the aneurysm from bursting, or to prevent rebleeding if the aneurysm has already burst.

Treatment for brain aneurysms involves surgical procedures such as:

• Microsurgical clipping. The surgeon will make a small opening in your skull and place a metal clip around the neck of the aneurysm to clamp blood supply and prevent further bleeding. For selected cases, microsurgical clipping may be combined with bypass surgery for better results.

• Cerebral bypass surgery and occlusion. The procedure begins with a bypass, where blood flow is rerouted away from the aneurysm to prevent the aneurysm from rupturing. This is done by connecting a bypass vessel before and after the aneurysm so blood supply is maintained in the other parts of the brain. This is followed by occlusion of the aneurysm with clips or coils.

• Endovascular embolisation. This is a minimally invasive procedure to block blood flow to the aneurysm. This can involve several techniques:

  • Endovascular coiling. Inserting small coils into the aneurysm to promote clotting and prevent rupture. For selected cases, additional devices such as intrasaccular devices, balloons, stents or support devices may be used.

  • Flow diversion. A finely meshed stent device is placed in the artery to divert blood flow away from the aneurysm, allowing it to close off over time.