What exactly is an aneurysm?

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A cerebral aneurysm (also known as an Intracranial or intracerebral aneurysm) is a weak or thin spot on a blood vessel in the brain that balloons out and fills with blood. The bulging aneurysm can put pressure on a nerve or surrounding brain tissue. It may also leak or rupture, spilling blood into the surrounding tissue (called a hemorrhage). Some cerebral aneurysms, particularly those that are very small, do not bleed or cause other problems. Cerebral aneurysms can occur anywhere in the brain, but most are located along a loop of arteries that run between the underside of the brain and the base of the skull. Brain aneurysms can occur in anyone, at any age. They are more common in adults than in children and slightly more common in women than in men.

Brain aneurysms can also be classified according to their size. The most common ones are “small” in that their diameter is 10 mm or less. “Giant” aneurysms are ones whose diameter is 25 mm or greater. In-between, from 11 to 15 mm and from 20 to 24 mm in diameter are the “large” and “near-giant” aneurysm sizes, respectively. There is a gray area of classification for brain aneurysms between 16 to 19 mm. Of all aneurysms, 95% are less than 25 mm in diameter; only 5% are “giant”.

Interestingly, certain differences exist between brain aneurysms of these different sizes. For most purposes, small and large brain aneurysms (i.e., together, 15 mm or less in diameter) behave in similar ways in that they tend to grow and rupture. In fact, more than 90% of these present following rupture (i.e., following “subarachnoid hemorrhage”). On the other hand, 75% of patients with near-giant and giant brain aneurysms (together, 20 mm or larger in diameter) are admitted to hospital with effects due to compression or irritation of brain structures surrounding these aneurysms (i.e., with “mass effect”, seizures, etc.); the remaining 25% of patients with near-giant and giant brain aneurysms are admitted following aneurysmal rupture. The risks of death and disability associated with bigger brain aneurysms, and particularly those in the back portion of the brain arteries ( “posterior cerebral circulation”), are significantly higher than smaller aneurysms in the front part of the brain arteries (“anterior cerebral circulation”).

Most brain aneurysms cause no symptoms and may only be discovered during tests for another, usually unrelated, condition. In other cases, an unruptured aneurysm will cause problems by pressing on areas within the brain. When this happens, the person may suffer from severe headaches, blurred vision, changes in speech, and neck pain, depending on the areas of the brain that are affected and the severity of the aneurysm.

Symptoms of a ruptured brain aneurysm often come on suddenly. They may include:

  • Sudden, severe headache (sometimes described as a “thunderclap” headache or “the worst headache of my life”)
  • Neck pain
  • Nausea and vomiting
  • Sensitivity to light
  • Blurred or double vision
  • Drooping eyelid
  • Fainting or loss of consciousness
  • Seizures

If you have any of the above symptoms or notice them in someone you know, see a health professional immediately.

And if you don’t have any of these symptoms but have a family history of aneurysms, GET SCANNED!  Aneurysms are treatable, you just need to know that you have one.  This is why The Joe Niekro Foundation has launched our Wanna Get Lucky campaign.  This campaign is designed to educate the public on the importance of early detection.  Help us spread the word by sporting one of these shirts TODAY.  If 1 in 15 people will develop an aneurysm, just think of the people you can reach in just one day when wearing one of these catchy and educational Tees?  Help join us in the fight and get one today.

Men’s and Women’s shirts in various colors and sizes are available for purchase on the website, so get yours today.  The life you save could be your own!

Help spread the importance of early detection as we STRIKEOUT aneurysms.
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