It’s critical to diagnose a stroke in progress because the treatment for stroke depends on the type of stroke, and, in some cases, the location of the injury to the brain. Other conditions with similar symptoms to stroke and transient ischemic attack (TIA) will need to be ruled out to diagnose stroke. Some of these include seizures, fainting, migraine headaches, heart problems or other general medical conditions.
Diagnostic tests examine how the brain looks, works and gets its blood supply. Most are safe and painless.
These tests fall into two categories: 1) imaging tests and 2) blood flow tests.
- CT (computed tomography) or CAT scan. It uses radiation to create a picture (like an X-ray) of the brain. It’s usually one of the first tests given to a patient with stroke symptoms. CT test results give valuable information about the cause of stroke and the location and extent of brain injury.
- MRI (magnetic resonance imaging). This test uses a large magnetic field to produce an image of the brain. Like the CT scan, it shows the location and extent of brain injury. The image produced by MRI is sharper and more detailed than a CT scan, so it’s often used to diagnose small, deep injuries.
- CTA (computed tomographic angiography). In CTA, a special contrast material (dye) is injected into a vein and images are taken of the blood vessels to look for abnormalities such as an aneurysm.
- MRA (magnetic resonance angiography). In this test, the blood vessels are imaged through a magnetic resonance scanner to locate a cerebral aneurysm.
Blood Flow Tests
These tests give information about the condition of arteries in your head and neck that supply blood to your brain.
- Cerebral angiography (or cerebral arteriography). Special substances are injected into the blood vessels and an X-ray is taken. This test gives a picture of the blood flow through the vessels. This allows the size and location of blockages to be reviewed. This test is very valuable in diagnosing aneurysms and malformed blood vessels.