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Diagnosing Alzheimer's Disease – The Medical Tests

A doctor diagnosing Alzheimer's has to eliminate any other cause for the symptoms, and that can take a long time and a lot of tests. There is only way to be 100% sure someone has AD and that is to examine the brain, which can only be done at a post mortem examination.

With an examination the doctor can tell the nature of the illness, whether it's possible the illness can be treated or reversed, and the areas in which the person can still function successfully. The doctor also needs to establish if there are any other health problems, the need for treatment for these other problems, and whether the treatment may make the mental problems worse.

Methods and procedures can vary from doctor to doctor, but a thorough evaluation of the symptoms should include a neurological and medical examination, consideration of the person's support system and an assessment of their remaining abilities, so that they can still be as independent as possible.

Evaluation can begin with questioning a close relative or friend of the person. They'll be asked questions such as what symptoms were observed, when were they first noticed, how has the person changed, and if they have other medical conditions.

Physical Examinations

The person will also have a physical examination to check for other health problems. Dementia can arise from other causes than AD, and the tests are to confirm or rule out other diseases with similar symptoms.

Problems with the thyroid gland can cause dementia, so that must be checked along with blood tests for problems such as anemia. Tests for evidence of infections, problems with liver and kidney function and diabetes will be performed too.

EEG, CT, MRI, PET, and SPECT Tests

If a physical examination doesn't show what is causing the symptoms an EEG (electroencephalogram) could be performed. The EEG measures the electrical activity of the brain and is to diagnose any abnormal brain functioning. Other high tech tests can also be used to help with diagnosing Alzheimers.

CT (computerized tomography) uses x-rays to examine the brain tissue. It is used to find evidence of tumors, strokes, blood clots etc. MRI (magnetic resonance imaging) can detect anomalies deep in the brain.

Other new procedures are PET scans (positron emission tomography) which displays areas of brain activity and SPECT scans (single photon emission computed tomography) which displays how the blood circulates through the brain. Recently Medicare even decided to pay for PET scans for patients who are difficult to diagnose.

Neurological, Mental and Psychiatric Tests

The doctor might also have a neurological examination done to show any changes in the functioning of the nerve cells of the spine or brain. This can involve the person balancing with their eyes closed and checking reflexes in the ankles and knees.

There should be a mental status test which involves asking the person about the current time, date and place. The examination will test the persons concentration, memory, ability to do simple calculations and do abstract reasoning.

A psychiatric exam can involve interviews with the person and their family as well as written tests. It can rule out depression which can give a memory loss similar to AD. Other exams evaluate the persons reasoning, writing and the ability to express ideas, vision-motor coordination and so on. It is more in-depth than the mental status test.

Ultimately all the results will be evaluated and a diagnosis will be made.

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