Common Tests or Labs to Diagnose Stroke
Because a stroke is a medical emergency (like a heart attack), it is often diagnosed in a hospital emergency room rather than a doctor’s office.
In addition to lab tests, the doctor will perform a physical exam and ask questions about your symptoms, medical history, and risk factors for stroke (such as smoking, high blood pressure, heart disease, and family history of stroke). The physical exam will include:
- Checking for problems with vision, movement, feeling, reflexes, understanding, and speaking
- Using a stethoscope to listen for sounds of abnormal blood flow in the carotid arteries of the neck
- Checking blood pressure
Below is a list of common tests and labs ordered to diagnose stroke, why you need them, and what they reveal about your condition.
|Test||Why Test?||What Happens?||Normal Result|
|CT scan of the brain||An imaging test done right after a suspected stroke to take clear, detailed pictures of the brain||A patient lies on a table that slides inside a large machine. Dye may be injected by syringe into the veins to help make clearer images.||This test will show if there is bleeding in the brain or damage to the brain cells from a stroke.|
|MRI scan of the brain||An imaging test done right after a suspected stroke to take clear, detailed pictures of the brain||A patient lies on a table that slides inside a large machine. Dye may be injected by syringe into the veins to help make clearer images.||This test can show changes in brain tissue and damage to brain cells from a stroke.|
|Carotid ultrasound (Doppler ultrasound)||An imaging test to take pictures of the insides of the carotid arteries, which supply blood to the brain||A patient lies on a table, and gel is put on the neck where the carotid arteries are located. A hand-held device (called a transducer) is moved back and forth against different spots on the neck.||This test will show whether plaque has narrowed or blocked the carotid arteries, which would reduce blood flow to the brain.|
|Carotid angiography||An imaging test to take pictures of the carotid arteries to confirm problems with blood vessels in the brain||A small tube is inserted into an artery (usually in the upper thigh) and moved up into one of the carotid arteries. Dye is injected into the carotid artery to help make the artery visible on x-ray pictures.||This test will show how blood flows through vessels in the brain and if there are problems with blood flow, such as narrowed blood vessels or blood leaking out of a vessel.|
|Magnetic resonance angiography (MRA) or CT angiography||Imaging tests that may be done to check for abnormal blood vessels in the brain||A patient lies on a table that slides inside a large machine. Dye may be injected by syringe into the veins to help make clearer images.||These tests show the large blood vessels in the brain and may give more information about the site of a blood clot and the flow of blood through the brain.|
|Electrocardiogram (ECG, EKG)||A test that records the heart’s electrical activity||Flat metal disks (called electrodes) connected to wires are attached to the chest with a sticky substance.||This test shows how fast the heart is beating, its rhythm, and the strength and timing of electrical signals passing through the heart. It may be done to help detect heart problems that may have led to a stroke.|
|Echocardiogram (ECHO)||An imaging test done to look at the structures of the heart||A patient lies on a table, and gel is put on the chest. A hand-held device (called a transducer) is moved back and forth over areas of the chest.||This test shows the size and shape of the heart and how well the heart’s chambers and valves are working. It may be done to help detect heart problems that may have led to a stroke.|
|Blood tests(e.g. clotting time, complete blood count, blood sugar, and cholesterol levels)||To measure various substances in the blood and how long it takes for the blood to clot||Blood is drawn with a syringe, typically from the arm.||Blood tests can help determine whether other disorders contributed to a stroke or are causing symptoms similar to a stroke.|