A brain aneurysm is a weak or thin spot in the wall of a brain artery that bulges or balloons out, filling with blood. If an aneurysm ruptures, it can lead to a life-threatening condition called a subarachnoid hemorrhage. You may be wondering, “What are the types of brain aneurysms?” Understanding the types of brain aneurysms is crucial for diagnosis, treatment, and prevention. This article explores the different types of brain aneurysms, their characteristics, and potential risks.
What Are the Types of Brain Aneurysms?
1. Saccular Aneurysms (Berry Aneurysms)
Saccular aneurysms are the most common type, accounting for about 80-90% of all brain aneurysms. They are often referred to as “berry” aneurysms because of their round, berry-like shape. These aneurysms have a narrow neck with a rounded dome. They typically form at the branching points of arteries in the brain.
Key Features:
- Commonly found in adults
- Higher risk of rupture compared to other types
- Often asymptomatic until they grow large or rupture
Symptoms, if unruptured: Headaches, vision changes, or neurological deficits if pressing on nearby nerves.
2. Fusiform Aneurysms
Fusiform aneurysms are less common and involve the entire circumference of the affected artery, causing it to bulge out in all directions. Unlike saccular aneurysms, they do not have a defined neck. These aneurysms are often associated with atherosclerosis (hardening of the arteries). They can occur in any large blood vessel in the brain.
Key Features:
- More common in people with vascular diseases
- Rarely rupture but can cause symptoms by compressing nearby brain structures
- Often found in the vertebrobasilar system at the back of the brain
Symptoms: Dizziness, vision problems, or difficulty with coordination, depending on the affected area.
3. Dissecting Aneurysms
Dissecting aneurysms occur when there is a tear in the inner lining of a blood vessel, allowing blood to flow between the layers of the artery wall. This can weaken the vessel and lead to an aneurysm or even a rupture. Dissecting aneurysms are more common in younger individuals and can result from trauma, connective tissue disorders, or spontaneous vessel wall degeneration.
Key Features:
- Associated with head or neck trauma
- Can cause stroke-like symptoms
- Higher risk of rupture in some cases
Symptoms: Sudden, severe headache, neck pain, or neurological deficits like weakness or speech difficulties.
4. Mycotic Aneurysms (Infectious Aneurysms)
Mycotic aneurysms are caused by infections that weaken the artery wall, leading to the formation of an aneurysm. These aneurysms are usually caused by bacterial infections, particularly from infective endocarditis (infection of the heart valves).
Key Features:
- Associated with systemic infections
- Higher risk of rupture due to fragile vessel walls
- Often multiple and irregularly shaped
Symptoms: Fever, chills, neurological symptoms depending on the aneurysm’s location, and signs of systemic infection.
5. Traumatic Aneurysms
Traumatic aneurysms develop after a head injury that damages the blood vessels in the brain. This type of aneurysm can form immediately after trauma or develop over time as the damaged vessel wall weakens. They are rare but carry a high risk of rupture.
Key Features:
- Directly linked to head trauma
- Irregular shape and fragile walls
- High likelihood of bleeding
Symptoms: Headache, seizures, or signs of increased intracranial pressure following a head injury.
Brain Aneurysm Risk Factors and Complications
While the types of aneurysms differ, several risk factors increase the likelihood of developing any brain aneurysm:
- Genetic Predisposition: Family history of brain aneurysms
- High Blood Pressure: Weakens artery walls over time
- Smoking: Damages blood vessels and increases rupture risk
- Age and Gender: More common in adults, particularly women
- Substance Abuse: Cocaine and other stimulants elevate blood pressure suddenly
Complications: The most serious complication of a brain aneurysm is rupture, leading to a hemorrhagic stroke, brain damage, or death. Even unruptured aneurysms can cause issues by pressing on nearby nerves or brain tissue.
Diagnosis and Treatment
Brain aneurysms are often diagnosed using imaging techniques such as:
- CT Scan: Detects bleeding in the brain
- MRI: Provides detailed images of brain structures
- Cerebral Angiography: Visualizes blood flow in brain arteries
Treatment Options:
- Monitoring: For small, unruptured aneurysms
- Endovascular Coiling: Inserting coils to block blood flow into the aneurysm
- Surgical Clipping: Placing a clip at the aneurysm’s base to prevent rupture
Neurosurgeon in Los Angeles
Understanding the different types of brain aneurysms is vital for early detection and effective management. While some aneurysms may never cause problems, others can be life-threatening if they rupture. If you have risk factors or symptoms suggestive of a brain aneurysm, promptly seeking medical evaluation can make a significant difference in the outcome. Consult a board-certified neurosurgeon today for treatment.
