Parkinson's Disease - Diagnosis

Highlights	Diagnosis	Lifestyle Changes
Introduction	Treatment	Resources
Symptoms	Levadopa (L-dopa)	References
Risk Factors	Medications
Complications	Surgery

Diagnosis

It is difficult to diagnose Parkinson's in early stages. At this time the disease is diagnosed almost primarily by its symptoms, and studies indicate that physicians make an incorrect initial diagnosis of Parkinson's disease in between 8% and 35% of cases. Even general neurologists have difficulties in correctly identifying the disease. Researchers are hopeful that objective and simple blood or imaging tests will be available in the near future to identify the disease early in its development.

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Medical and Personal History

A medical and personal history should include any relevant symptoms as well as any medications being taken, and exposure to environmental toxins is very important.

Diagnosing by Symptoms

Early Symptoms. Early treatment may help slow progression, so an early diagnosis of Parkinson's is highly desirable. Early symptoms are often mild however, so Parkinson's disease can be missed, particularly in young adults. Repeated assessment of symptoms over time is important to improving the accuracy of diagnosis. Too often, for example, a younger person with Parkinson's may be diagnosed with mental illness, because even the physician may suspect the disease only in older people.

Parkinson's may be suspected in patients with the following symptoms:

Slowness and difficulty of movement. These are usually the first symptoms, so the patient will be asked to walk and probably to get out of a chair, preferably a deep one. (Early gait disturbance, however, often indicates a disease other than Parkinson's disease.)
A tremor when their limb is relaxed. (As many as 25% of Parkinson's patients, however, will not have a tremor.)
Symptoms on one side of the body.
A powerful early response to the drug levodopa (the primary treatment for Parkinson's). It should be noted that some patients with a very similar condition called multiple system atrophy will have a good initial response to levodopa, but it is not usually sustained.

Later Symptoms. In later stages of Parkinson's disease, the symptoms are usually unmistakable, and the problem can often be diagnosed using simple physical tests and a medical and personal history.

Imaging Techniques

Imaging techniques, such as computerized tomography (CT), magnetic resonance imaging (MRI), or positron-emission tomographic (PET) may be very useful in ruling out disorders with similar symptoms, such as progressive supranuclear palsy. They are not usually necessary when physical symptoms of Parkinson's disease are obvious.

CT stands for computerized tomography. In this procedure, a thin X-ray beam is rotated around the area of the body to be visualized. Using very complicated mathematical processes called algorithms, the computer is able to generate a 3-D image of a section through the body. CT scans are very detailed and provide excellent information for the physician.