What Is An Aneurysm

A brain aneurysm, also called a cerebral aneurysm, is an abnormal bulge or ballooning in a blood vessel supplying your brain (cerebrum). The weakened area forms a sac or small balloon that fills with blood. Usually brain aneurysms occur at branching points of arteries.

Brain aneurysms can rupture and cause bleeding into your brain. Usually this occurs in the area between your brain and the surrounding membrane (the arachnoid), called the subarachnoid space, causing a subarachnoid hemorrhage. Many small brain aneurysms, especially those located on the arteries in the front part of your brain, have a low risk of rupture. However, ruptured brain aneurysms can lead to stroke and death.

Your doctor will evaluate you and discuss your symptoms. Your doctor may use tests to diagnose a ruptured or unruptured brain aneurysm and determine its size, location and other characteristics, and assess the aneurysm’s risk of rupture. Radiologists who specialize in brain imaging conduct imaging tests.

Tests May Include

  • Cerebral arteriogram. In a cerebral arteriogram (also called cerebral angiogram), a doctor inserts a long thin tube (catheter) into an artery in your leg and guides it through your blood vessels to the arteries in your neck that lead to your brain. A specialist injects dye into the arteries, which creates a map of your arteries and the aneurysm on X-rays.
  • Cerebrospinal fluid examination. If your doctor suspects a subarachnoid hemorrhage, but the hemorrhage doesn’t appear on a CT scan, your doctor may examine fluid from your spinal column (cerebrospinal fluid) for the presence of blood. A doctor will insert a needle into your lower back to withdraw a small amount of spinal fluid in a procedure called a spinal tap or lumbar puncture.
  • Computed tomography (CT) scan. A CT scan uses a series of X-rays to create a detailed, three-dimensional image of your brain. CT scans can help detect bleeding in your brain. CT scans reveal blood flow in your brain and show the aneurysm’s location. Sometimes a doctor may inject a dye into a vein to highlight blood flow in your arteries and veins (CT angiogram) and provide additional detail regarding the appearance of the brain aneurysm.
  • Magnetic resonance imaging (MRI). An MRI uses powerful magnets and radio waves to create detailed images of your brain and show the aneurysm’s location. Sometimes your doctor may inject a dye into a blood vessel to view the arteries and veins, highlight blood circulation and locate an unruptured or ruptured brain aneurysm (magnetic resonance angiogram).

Screening for Brain Aneurysms

If you have a significant family history of brain aneurysms or if you have autosomal dominant polycystic kidney disease, you’re considered to be at high risk for an aneurysm, and your doctor may recommend screening. Common screening tests include magnetic resonance angiography or computed tomography angiography.

Your treatment team will work closely with you to develop an individualized treatment plan to prevent a brain hemorrhage based on your brain aneurysm’s location, the aneurysm’s risk of rupture and your medical condition. We treat brain aneurysms in many ways, including procedures using minimally invasive techniques.

Treatment Options

  • Monitoring. If doctors determine your brain aneurysm has a low risk of rupture, they may recommend monitoring your condition with regular follow-up appointments.   The size and location of a brain aneurysm affects the risk of a brain hemorrhage.  As a result, we will consider these and other factors in determining your risk of rupture, and review options for long-term management.
  • Endovascular embolization. In endovascular embolization, a doctor inserts a long thin tube (catheter) into an artery in your groin and guides it to your brain using X-ray imaging. Your surgeon then guides detachable platinum coils through the catheter, placing the coils in the aneurysm (aneurysm coiling). The coils fill the aneurysm, which reduces blood flow into the aneurysm sac and causes the blood to clot. Your surgeon also may insert a balloon or tube (stent) in the artery to keep it open and then perform the aneurysm coiling.Doctors often use endovascular therapy to treat ruptured and unruptured aneurysms and may offer it as an alternative to surgery. Endovascular procedures sometimes need to be performed again. You’ll have regular follow-up appointments with your doctor to monitor for any changes.
  • Surgery. During the surgery, done under general anesthesia, your surgeon makes an incision in your scalp, creates a window in your skull, locates the brain aneurysm and places a metal clip across its neck to prevent rupture and stop the blood flow to the aneurysm. If the aneurysm is large, your surgeon may use a piece of an artery from another part of your body to connect your blood vessels and bypass the aneurysm.Surgical techniques have greatly reduced the risks of this surgery. Your risk depends on the size, location, and other characteristics of your brain a

Learn more from the Brain Aneurysm Foundation