Tests and diagnosis

By Mayo Clinic Staff

Doctors can nearly always determine that you have dementia, but there's no specific test that confirms you have vascular dementia. Your doctor will make a judgment about whether vascular dementia is the most likely cause of your symptoms based on the information you provide, your medical history for stroke or disorders of the heart and blood vessels, and results of tests that may help clarify your diagnosis.

Lab tests

If your medical record doesn't include recent values for key indicators of the health of your heart and blood vessels, your doctor will test your:

  • Blood pressure
  • Cholesterol
  • Blood sugar

He or she may also order tests to rule out other potential causes of memory loss and confusion, such as:

  • Thyroid disorders
  • Vitamin deficiencies

Neurological exam

Your doctor is likely to check your overall neurological health by testing your:

  • Reflexes
  • Muscle tone and strength, and how strength on one side of your body compares with the other side
  • Ability to get up from a chair and walk across the room
  • Sense of touch and sight
  • Coordination
  • Balance

Brain imaging

Images of your brain can pinpoint visible abnormalities caused by strokes, blood vessel diseases, tumors or trauma that may cause changes in thinking and reasoning. A brain-imaging study can help your doctor zero in on more likely causes for your symptoms and rule out other causes.

Brain-imaging procedures your doctor may recommend to help diagnose vascular dementia include:

  • Computerized tomography (CT). For a CT scan, you'll lie on a narrow table that slides into a small chamber. X-rays pass through your body from various angles, and a computer uses this information to create detailed cross-sectional images (slices) of your brain. This test is painless and takes about 20 minutes. A CT scan can provide information about your brain's structure; tell whether any regions show shrinkage; and detect evidence of strokes, mini strokes (transient ischemic attacks, blood vessel changes or tumors. Sometimes you'll receive an intravenous (IV) injection of a contrast agent that will help highlight certain brain tissues.
  • Magnetic resonance imaging (MRI). An MRI uses radio waves and a strong magnetic field to produce detailed images of your brain. You lie on a narrow table that slides into a tube-shaped MRI machine, which makes loud banging noises while it produces images. The entire procedure can take an hour or more. MRIs are painless, but some people feel claustrophobic inside the machine and are disturbed by the noise. MRIs can provide even more detail than CTs about strokes, mini strokes and blood vessel abnormalities.

Carotid ultrasound

This procedure uses high-frequency sound waves to determine whether your carotid arteries — which run up through either side of your neck to supply blood to brain — show signs of narrowing as a result of plaque deposits or structural problems. Your test may include a Doppler ultrasound, which shows the movement of blood through your arteries in addition to structural features.

Neuropsychological tests

This type of exam assesses your ability to:

  • Speak, write and understand language
  • Work with numbers
  • Learn and remember information
  • Develop a plan of attack and solve a problem
  • Respond effectively to hypothetical situations

Neurospychological tests sometimes show characteristic results for people with different types of dementia. People with vascular dementia may have an exceptionally hard time analyzing a problem and developing an effective solution. They may be less likely to have trouble learning new information and remembering than are people with Alzheimer's unless their blood vessel problems affect specific brain regions important for memory. However, there's often a lot of overlap in exam results for people with vascular dementia and people who have Alzheimer's disease.

Apr. 30, 2011