Brain Aneurysm – Causes, Symptoms, Diagnosis, and Treatment
A brain aneurysm is a potentially life-threatening condition where a blood vessel in the brain can rupture. You may not know you have a brain aneurysm until it is large and causing symptoms, or detected upon routine investigation. Although serious, it is a manageable medical conditions when identified and treated early. It is important to seek medical care as early as possible and follow medical professional’s advice on the best options for treatment and management.
What is a Brain Aneurysm?
A brain aneurysm, also known as a cerebral aneurysm, is a weak or thin spot in the wall of a blood vessel in the brain that balloons out and fills with blood. Over time, this bulging area can become fragile and there is the risk of it rupturing. This can result in bleeding in the brain, a condition known as a subarachnoid haemorrhage, which may be fatal. While some aneurysms remain small and asymptomatic, others can grow and exert pressure on surrounding brain tissue or nerves.
Is a brain aneurysm the same as a stroke?
A brain aneurysm is not a stroke but can result in a stroke. An aneurysm is a ballooning or bulging of a blood vessel, which can occur anywhere in the body. As long as the blood vessel remains intact and there is no disturbance in the blood flow, it will not reduce oxygen supply to the affected body part like the brain. However, when a brain aneurysm ruptures then it can cause a stroke.
A rupture (“bleeding aneurysm”) can interrupt oxygen supply to the brain tissue. This reduced oxygen supply can lead to death of brain tissue, which is commonly known as a stroke (cerebrovascular accident or CVA). Most strokes are due to a blockage, like an artery narrowing (atherosclerosis) and a blood clot, blocking blood flow (ischaemic stroke) while a ruptured aneurysm can result in the less common haemorrhagic stroke.
Causes of Brain Aneurysms
The exact cause of brain aneurysms is not always clear, but several factors contribute to their development:
- Genetics: A family history of aneurysms can increase the likelihood of developing one.
- High Blood Pressure (Hypertension): Elevated blood pressure can weaken blood vessel walls.
- Smoking: Tobacco use is a significant risk factor for aneurysm formation and rupture.
- Head Injury: Trauma to the head may lead to aneurysm development.
- Infections: Certain infections can damage blood vessels and lead to aneurysms.
- Other Conditions: Disorders such as polycystic kidney disease and connective tissue disorders can increase susceptibility.
Symptoms of a Brain Aneurysm
Many brain aneurysms are asymptomatic until they grow large or rupture. Symptoms depend on the aneurysm’s size, location, and whether it has ruptured:
Unruptured Aneurysms
An intact (unruptured) aneurysm does not usually cause any symptoms when small. As it grows larger, the following symptoms may arise:
- Headaches
- Vision problems (such as blurred or double vision)
- Pain above or around the eye
- Difficulty speaking or swallowing
Ruptured Aneurysms
A rupture aneurysm is a medical emergency. It can lead to death within a short period of time and needs immediate medical attention.
- Sudden and severe headache
- Nausea and vomiting
- Loss of consciousness
- Seizures
- Stiff neck
- Sensitivity to light
- Weakness or numbness in limbs
Diagnosis and Treatment
Detecting a brain aneurysm often requires advanced imaging techniques:
- CT Scan: A computed tomography scan can quickly identify bleeding in the brain.
- MRI: Magnetic resonance imaging provides detailed images of the brain and blood vessels.
- CT Angiography (CTA): Combines CT imaging with contrast dye to visualize blood vessels.
- Cerebral Angiography: An invasive test that uses a catheter to inject dye directly into brain blood vessels for detailed imaging.
Treatment options depend on the size, location, and risk of rupture of the aneurysm. Options include:
- Observation: Small, unruptured aneurysms may be monitored with regular imaging, particularly if the risk of rupture is low.
- Endovascular Coiling: A minimally invasive procedure where coils are inserted into the aneurysm to block blood flow and prevent rupture.
- Surgical Clipping: A neurosurgical procedure where a clip is placed at the base of the aneurysm to cut off blood supply.
- Medications: Drugs to manage high blood pressure or pain may be prescribed.
Prevention and Prognosis
It is not always possible to prevent brain aneurysms but addressing risk factors significantly lower the risk of an aneurysm growing or rupturing. Quitting smoking, controlling blood pressure, and maintaining a healthy lifestyle are some of the ways to reduce risk of complications. The prognosis for individuals with a brain aneurysm depends on the size, location, and whether it has ruptured. Early diagnosis, intervention and regular monitoring are crucial to improving the outcome.