Brain aneurysm (intracranial aneurysm) FAQs answered by a specialist

Brain aneurysms are swollen blood vessels in the brain, which can often be at risk of rupturing and causing a brain haemorrhage. Most often, symptoms become noticeable only once the aneurysm has ruptured, leading to life-threatening conditions. Mr Christos Tolias has spent many years treating people with brain aneurysms and in this article, he answers the most frequently asked questions.

What is a brain aneurysm?

Aneurysms can occur anywhere in your body, including the brain. Brain aneurysms, however, have a different aetiology. Between 2-5% of the UK population may have an aneurysm in the brain arteries (cerebral arteries) at some point in their lives. When a person experiences an aneurysm, it means that somewhere in their body, there is a weak blood vessel that has become swollen and filled with blood. An aneurysm in the brain can be referred to simply as a brain aneurysm, or medically as an intracranial aneurysm.

When this occurs in the brain, the brain tissue and nerves can be affected. If the aneurysm bursts, blood can spill into the brain tissue – this is known as a brain haemorrhage . Often however the blood spills around the brain - this is known as subarachnoid haemorrhage

When a brain or subarachnoid haemorrhage occurs, the patient is at risk of various serious health complications:

• Stroke and severe disability
• Brain damage
• Coma
• and , unfortunately, in many cases, death

Fortunately, not all brain aneurysms result in major health complications . Small aneurysms have less risk of haemorrhaging and there are treatments to lessen and even prevent the damage from unruptured and ruptured aneurysms.

Causes and risk factors

In short, aneurysms are caused by weak blood vessels in the brain. The precise reason why this occurs is unclear, but there are a variety of known potential causes – some of these risk factors we have the power to influence:

• Smoking
• High blood pressure (hypertension)
• Recreational drug use, particularly cocaine

Other factors are unavoidable, largely those that result from an inherited predisposition of weak blood vessels, which can ultimately lead to a brain aneurysm. These are:

• A family history of aneurysms
• Being over 40 years old
• Your gender – more women experience brain aneurysms than men
• Polycystic kidney disease (PKD). 1 in 20 people with PKD develop a brain aneurysm

· Having a condition known as connective tissue disease, such as, Ehlers-Danlos syndrome or Marfan syndrome .

· Having a congenital heart disease that results in the main artery in the body becoming narrow

· Some rare infections, especially of the heart valves.

What are the symptoms of a brain aneurysm?

Usually, brain aneurysms only cause symptoms once they have already ruptured. Having said that, very rarely unruptured aneurysms can sometimes show symptoms:

• A slight loss of vision or double vision
• Pain around your eye or above it
• Numbness on one side of your face
• Difficulty speaking
• Headaches
• Loss of balance
• Difficulty concentrating

If you notice any of these symptoms, you should visit a doctor as soon as possible.

If a brain aneurysm does rupture, there are a number of sudden symptoms that can be experienced:

• An sudden severe headache (worst ever)
• The feeling of nausea and/or the need to vomit
• Neck stiffness/neck pain
• Light sensitivity
• Blurred vision (or double vision)
• Confusion
• Loss of consciousness
• Weakness on one side of the body

In cases with these sudden symptoms, there is a medical emergency and no hesitation should be taken. Call 999 immediately so that an ambulance can arrive as soon as possible.

How is a brain aneurysm diagnosed?

Unless the aneurysm ruptures, it will likely go unnoticed. However, they can be identified during imaging tests that were intended to test for other conditions.

There are a few tests available which can diagnose brain aneurysms and assist in choosing the best treatment method:

• A brain MRI (magnetic resonance imaging) scan - this is usually used to detect brain aneurysms that have not ruptured. Also, it can allow your medical specialist to look at the arteries in detail.
• A CT scan . If your presentation suggest that you’re experiencing a brain haemorrhage, a CT scan will likely be used to detect any bleeding. CT head scans are so efficient that they can detect blood within a few hours of bleeding
• An angiography . A dye is administered into the brain arteries via a catheter (narrow tube). An x-ray is then taken to show how well blood is flowing through the vessels.

How is a brain aneurysm treated?

Not every brain aneurysm will need to be treated. If an aneurysm is very small, unruptured and not accompanied by serious factors that could signal a high risk of rupture, then it can be left alone and sometimes regularly monitored with MRI scans.

In cases where there is a high risk of rupture, your specialist will insist on treatment. There are two types of treatment-neurosurgical clipping and endovascular coiling. Both aim to stop blood from continuing to flow into the aneurysm, therefore preventing a rupture.

In emergency situations in which the brain aneurysm has already ruptured, you’ll will need to be admitted to a highly specialised unit, receive intensive medical treatment and then have the ruptured aneurysm repaired via neurosurgical clipping or endovascular coiling. Even after that patients need to remain in hospital for a considerable period of time in order to treat all the potential problems that often follow the original bleed.

Mr Christos Tolias is a neurosurgeon with over 30 years of experience. Visit Mr Tolias’ Top Doctors profile to book a consultation and discover how he can assist you in looking after your health.