Your doctor will diagnose a stroke based on your symptoms, your medical history, a physical exam, and test results. Your doctor will want to find out the type of stroke you’ve had, its cause, the part of the brain that is affected, and whether you have bleeding in the brain. If your doctor thinks you’ve had a transient ischemic attack (TIA), he or she will look for its cause to help prevent a future stroke.
Your doctor will order tests to help rule out other health problems with similar signs or symptoms.
Your doctor will order an imaging test to look at the blood vessels in your brain. This will help determine what type of stroke you have and where exactly it happened. The quicker these tests can be done, the better your doctor can treat you. Tests to diagnose stroke include the following:
- Computed tomography (CT) uses X-rays to take clear, detailed pictures of your brain. It is often done right after a stroke is suspected. A brain CT scan can show if there is bleeding in the brain or damage to the brain cells from a stroke.
- Magnetic resonance imaging (MRI) uses magnets and radio waves to create pictures of your brain. An MRI may be used instead of—or in addition to—a CT scan to diagnose a stroke. This test can detect changes in brain tissue and damage to brain cells.
- Other imaging tests to look for narrowed blood vessels in the neck or an aneurysm or tangled blood vessels in the brain.
Your doctor may also order the following blood or heart tests.
- Blood tests. Your doctor may test the blood and platelet count and glucose (sugar) levels in your blood to make sure they are stable and to see if a certain medicine can treat your stroke. Your doctor may also do blood tests to see how well your blood is clotting and to look for muscle damage.
- Electrocardiogram (EKG). An EKG can help detect heart problems that may have led to a stroke. For example, this test can help diagnose atrial fibrillation or a previous heart attack.
- Lumbar puncture (also called a spinal tap), if the imaging scan does not detect any bleeding in the brain but your doctor still thinks you may have had a hemorrhagic stroke. The doctor will use a needle to collect fluid from around your spine. The fluid will be tested for substances from broken-down blood cells.
Medical history and physical exam
Your doctor will ask you or a family member about your risk factors for stroke. Tell your doctor if you or someone in your family has had a stroke. Your doctor will also ask about your signs and symptoms and when they began.
During the physical exam, your doctor will check you for:
- Coordination and balance
- Mental alertness
- Numbness or weakness in your face, arms, and legs
- Trouble speaking or seeing clearly
- The exam will help your doctor determine how severe your stroke was and plan your treatment.
Your doctor will look for signs of carotid artery disease, a common cause of ischemic stroke. He or she will listen to your carotid arteries with a stethoscope. A whooshing sound called a bruit may suggest changed or reduced blood flow due to plaque buildup in the carotid arteries.