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Brain Aneurysm Risk Factors & Symptoms

Risk Factors for Brain Aneurysm

Brain aneurysms can be caused by a number of factors, but some people are at a higher risk for brain aneurysm. You may be at increased risk if you have any of the following factors or medical conditions:

  • A strong family history (more than one immediate family member with a brain
    aneurysm)
  • Previous history of brain aneurysm
  • Finnish ancestry
  • Polycystic Kidney Disease
  • Collagen Vascular Disease, such as Ehlers Danlos Syndrome or Marfan Syndrome
  • Female gender
  • Fibromuscular Dysplasia (FMD)
  • Arteriovenous Malformations (AVM)

Risk factors for developing or having bleeding from an aneurysm also include high blood pressure, smoking, and excessive alcohol use. 

If you have any risk factors for developing an aneurysm, it's important discuss screening tests and treatment options with your healthcare provider.

Most unruptured aneurysms are  small and don't cause obvious symptoms. At times, unruptured aneurysms are found when they grow and press on nerves in the area, causing symptoms like blurred or double vision. Symptoms of a ruptured aneurysm occur when the aneurysm bursts (causing bleeding into the brain) triggering a severe headache or loss of consciousness.

Symptoms of an Unruptured Brain Aneurysm

Most small unruptured aneurysms cause no symptoms at all. Unruptured aneurysms may be found by chance when a person is having tests for other reasons, such as chronic headaches or carotid artery disease. People with an unruptured aneurysm may experience symptoms:

  • Blurred or double vision
  • Pain above or behind the eye
  • Dilated pupil
  • Drooping eyelid
  • Eye movement problems
  • Weakness, numbness, or difficulty speaking
  • Chronic headache

Symptoms of a Ruptured Aneurysm

Most aneurysms will have no symptoms until they've ruptured. When this happens, blood from the burst aneurysm goes into the spinal fluid in the space around the brain; this type of bleeding also is called a subarachnoid hemorrhage. Symptoms of a ruptured aneurysm come on rapidly and can include:

  • Sudden and severe headache, often described as the worst ever felt
  • Stiff neck
  • Nausea and vomiting
  • Sudden change in mental status (drowsiness or loss of consciousness)
  • Sudden pain above or behind the eye
  • Sudden blurred or double vision
  • Trouble walking or dizziness
  • Sudden weakness and numbness
  • Eye sensitivity to light
  • Seizure

Bleeding into the brain can cause damage to brain cells, increased pressure in the brain, and the narrowing of blood vessels in the brain (vasospasm).

If you or someone you know is having symptoms of an aneurysm, it's important to call 911 and quickly seek emergency medical attention for diagnosis and treatment.