Medical Tests Used in Stroke Evaluation

A stroke can affect so many of your abilities - from vision to speech to arm and leg movements to sensation to coordination. A stroke, unlike most other neurological problems, usually occurs relatively suddenly and quickly. One of the most important skills a neurologist or another member of the stroke care team uses is the ability to promptly and accurately distinguish the difference between a stroke and other less urgent neurological problems.

In fact, before sophisticated imaging tests were developed, medical doctors could precisely determine if a patient was having a stroke within minutes. Even with the advancement of imaging studies and medical tests, modern day medical students are taught how to methodically identify the specific location of a stroke in the brain.

In addition to imaging studies, there are also various medical tests that are used in stroke evaluation. Some of these tests can help determine whether there are other health issues that need to be taken care of in addition to a stroke. Some are used to help guide safe medical treatment after a stroke, especially treatment with blood thinners. Some are used to assess for stroke risk factors. And some of these tests are used to help figure out whether there is another medical problem besides a stroke that may be mimicking a stroke. Not every stroke patient needs every single one of these tests- most patients only need a few.

Here is a list of some of the medical tests that you may need if you have had a stroke or need to be evaluated for a possible stroke.

Blood Tests

Blood tests can evaluate certain risk factors or consequences of a stroke.

  • CBC/ Complete Blood Count: A CBC can help gauge whether there is a problem with the blood cells, with the electrolytes of the body, or whether there is inflammation or an infection.
  • PT/PTT Prothrombin Time/ Partial Thromboplastin Time: These blood tests measure the time it takes for blood to clot. This is very important in closely monitoring the emergency blood thinning treatments that are sometimes used for stroke treatment. 
  • Cholesterol/Lipid Panel: A careful analysis of fat and cholesterol levels can help assess the risk of vascular disease.
  • Special Blood Tests: Sometimes specific tests such as homocysteine, lupus anticoagulant, rheumatoid factor, anti-nuclear antibody and others are requested when there is a suspicion of an autoimmune disease or another uncommon disease.
  • Blood sugar: This can determine whether a person has untreated diabetes, which is a stroke risk factor.
  • Hemoglobin a1c: Can reveal whether the stroke patient has had high blood sugar over the past few months.
  • Arterial Blood Gas: Measures oxygen and carbon dioxide in the blood, which can help assess heart and lung function

Urine Analysis

  • Glucose: Glucose in the urine is a sign of diabetes.
  • Drug toxicity: Many recreation/illegal drugs can cause a stroke- especially cocaine and methamphetamine. Some drugs and medications do not necessarily cause a stroke, but can temporarily impair judgment and thinking, making a patient behave as if he is having a stroke.

    Specialized Tests

    • EKG: Evaluates heart function and can reveal whether there is a heart attack or a heart rhythm abnormality.
    • Cerebrospinal fluid: Can determine whether there is an infection of the fluid that surrounds the brain and spinal cord -which may cause a stroke or manifest similarly to a stroke. Can also show characteristics of multiple sclerosis, which may mimic a stroke.
    • Evoked potentials: Measures electrical activity in the brain and is often a helpful clue in the diagnosis of multiple sclerosis.
    • EEG: This is a brain wave test that evaluates electrical activity. Can show whether there are seizures, which may initially be confused with a stroke. There are often characteristic EEG changes that accompany a stroke.
    • EMG: A nerve and muscle test used to evaluate neuropathy, which may be confused with a stroke.

    Sources

    Ropper, Allan, Samuels, Martin, Klein, Joshua, Principles of Neurology, 10th Edition, McGraw-Hill, 2014

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