Diagnosing Brain Aneurysms
Neuroscience Institute Swedish Cerebrovascular Center
The aneurysm experts at the Swedish Neuroscience Institute (SNI) use a variety of imaging tests to diagnose a brain aneurysm. You may have one or more of the following imaging exams:
MRI Angiography (MRA)
CT Scan and CT Angiography (CTA): A CT scan of the brain is often the first test your neurosurgeon will request. A CT scanner uses X-rays to create images of very thin sections of your brain that help identify the location and size of an aneurysm. It also helps determine if there is blood leaking from the aneurysm. A CTA is a CT scan taken after a small amount of dye is injected. The CTA produces images of the blood vessels and can show aneurysms.
MRI or MRI Angiography (MRA): An MRI or MRA are additional methods of determining the location, size and condition of an aneurysm, and whether the aneurysm is bleeding into the skull. MRI and MRA use magnets, radio-wave energy and computers to create images. The images can be either 3-D or 2-D. MRI and MRA are very similar, except an MRA uses a small amount of dye to help highlight the aneurysm.
Cerebral Angiogram: The neurosurgeon will use a cerebral (brain) angiogram to see how the blood is flowing through the arteries and veins in your brain. During this X-ray test, a small amount of dye is injected through a tiny tube (catheter) into the blood vessel in the brain to make it easier to see the blood flow. The angiogram can identify defects in a blood vessel, such as a blockage or a weak area that may develop into an aneurysm. It is often used to detect very small aneurysms.
Lumbar Puncture: Your doctor may request a lumbar puncture if he or she suspects your aneurysm is bleeding into your brain. A needle is inserted into the lower-back portion of the spine to withdraw a small amount of spinal fluid. The fluid is examined to determine if there is blood present.