When it comes to brain health, terms like "stroke" and "aneurysm" can be confusing. Both are serious medical conditions affecting blood vessels in the brain, but they have important differences in how they develop and what happens in the body. Neurologist Pierre Fayad, MD, helps break down these differences.

The key difference

An aneurysm is a bulging spot in a brain blood vessel. A stroke, on the other hand, is a loss of brain function from brain damage that happens in one of two ways:

1. From loss of blood flow to the brain from a vessel blockage.
2. From blood leakage from a broken vessel with bleeding in the brain. 

A stroke is an emergency that requires immediate medical attention, as every minute counts in restoring blood flow to the brain and preventing irreversible damage. In contrast, while an aneurysm poses serious risks, it may not present immediate symptoms – until a rupture occurs.

Understanding aneurysms

"A brain aneurysm is an abnormal pocket that forms in the wall of the arteries or blood vessels inside the brain," explains Dr. Fayad. These weak spots usually develop where blood vessels divide or branch off. While this might sound scary, they're more common than you might think – about 3% to 5% of people have them.

Many people don't know they have an aneurysm until it's found during brain imaging done for other reasons. Thanks to better scanning technology, doctors are finding more unruptured aneurysms early. While an unruptured aneurysm can exist without causing problems, if it bursts, it causes a specific and severe type of stroke called subarachnoid hemorrhage.

Warning signs of a ruptured aneurysm

When an aneurysm bursts, the warning signs are dramatic. "The typical presentation is the worst headache someone has ever experienced," Dr. Fayad says. "It's what we call a ‘thunderclap headache’ because of the speed and intensity with which it presents. Some people may even lose consciousness immediately.”

Warning signs include:

• Sudden, severe headache (especially if different from usual headaches).
• Stiff neck.
• Nausea and vomiting.
• Loss of consciousness.
• Vision problems, or double vision.
• Weakness.

What happens when an aneurysm ruptures?

A ruptured brain aneurysm is one of the most dangerous types of stroke. "About 20% to 25% of people with a ruptured aneurysm will die even before getting medical care," Dr. Fayad notes. "And even after they get medical care, the risk of death in the hospital still approaches 20%."

When an aneurysm bursts, it releases blood mostly around the brain or in the brain itself. This type of bleeding, known as a subarachnoid hemorrhage, makes up about 7% of all strokes.

Treatment options

Not all unruptured aneurysms need immediate treatment. Small, stable aneurysms in low-risk areas might just need monitoring for growth in size. However, doctors may recommend intervention if they grow or show other concerning changes.

There are two main ways to treat brain aneurysms:

1. Open surgery (craniotomy): Surgeons place a clip at the base of the aneurysm.
2. Coiling: Doctors thread a catheter through blood vessels to place tiny coils in the aneurysm, causing it to clot. This stops blood flow and prevents the vessels from further rupturing.

"About 80% of aneurysms are now treated through coiling, which is minimally invasive," says Dr. Fayad. The choice between open surgery and coiling depends on the patient's condition and the aneurysm's location and size.

Lowering your risk

Several factors can increase your risk of developing or rupturing a brain aneurysm. Dr. Fayad emphasizes these key prevention steps:

• Stop smoking – it's a major risk factor.
• Control blood pressure – your systolic, or upper, blood pressure should be below 130.
• Avoid illegal drugs, especially cocaine and methamphetamines.
• Know your family history – genetic factors can increase your stroke risk.
• Eat a healthy diet.

Be aware that women, especially after menopause, face a higher risk of aneurysm rupture. Pregnancy can also be a concerning time for women with aneurysms, requiring careful monitoring.

When to seek help

"Having the worst headache you've ever had, especially if it's different than your usual headache or migraine, should prompt you to go immediately to the emergency room," Dr. Fayad says. This is particularly important if you have risk factors or additional symptoms.

As the region's leading Joint Commission Certified Comprehensive Stroke Center, Nebraska Medical Center handles 40 to 50 ruptured aneurysm cases yearly, well above the recommended minimum of 10 to 20 cases. "Experience and training of the multidisciplinary health professionals has a lot to do with outcomes," Dr. Fayad says.

Patients with ruptured aneurysms receive care in Nebraska Medical Center’s dedicated Neuroscience Intensive Care Unit. This specialized unit is crucial for monitoring and treating potential common complications that can occur in the days and weeks after a rupture, including a serious condition called delayed vasospasm that can cause additional brain damage and disability.

Act fast

Remember, a ruptured brain aneurysm is a serious emergency. If you think you or someone near you may be having a stroke, call 911. Knowing the warning signs and risk factors – and acting fast if symptoms appear – could save your life.