Detection and Treatment Guide Updated 2017 Detection-and-Treatment-2017 | Page 12

DIAGNOSIS
When a ruptured aneurysm is suspected, a head CT (computerized tomography)
scan is performed. This is a painless, non-invasive X-ray exam. A CT scan will show
if there has been bleeding in the brain. However, a basic CT scan does not usually
show the cause of the bleeding. Using a technique called computerized tomography
angiography (CTA), in which a contrast dye is injected into the bloodstream, the
brain’s blood vessels are highlighted and aneurysms can be seen using special
imaging techniques.
Sometimes an angiogram is needed to provide a better view of the aneurysm
and blood vessels. An angiogram may be done on an emergency basis after a
subarachnoid hemorrhage is detected. For someone with an unruptured aneurysm,
the angiogram is often performed as an outpatient procedure in an angiography suite
of a hospital.
During an angiogram, an area of the groin is numbed and the doctor inserts a
catheter into an artery in the groin. The catheter is then advanced to the appropriate
area, and a contrast dye is injected through it. The dye highlights the arteries, and
X-ray images are taken.
Sometimes magnetic resonance imaging (MRI) or magnetic resonance angiography
(MRA) are used to screen patients for aneurysms. MRI and MRA, which use
computer-generated radio waves and a powerful magnetic field, do not expose the
patient to any ionizing radiation (X-rays).
CTA, MRA, or an angiogram may also be used to diagnose unruptured aneurysms.
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