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 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 bleeding 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. Microsurgical clipping may be combined with bypass surgery for better results.
  • Endovascular coiling. In this minimally invasive procedure, a catheter is inserted into an artery in your leg or groin and maneuvered through your network of blood vessels to the aneurysm. Platinum coils are then released into the aneurysm to induce blood clot formation, thereby preventing the bulge from growing further or rupturing.
  • Bypass surgery. This procedure reroutes blood flow away from the bulging aneurysm by placing a small stent (flexible mesh tube) in the artery. It is used for larger brain aneurysms where clipping or coiling may not be as effective.
  • Occlusion. This open surgery blocks off blood flow to the aneurysm and the surrounding part of the weakened artery using tiny coils. It is usually performed together with bypass surgery.
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