How Is Parkinson’s Disease Diagnosed?

There is no ‘test’ that can give a definite diagnosis of Parkinson’s disease. Usually, your regular doctor will refer you to a neurologist if your symptoms suggest Parkinson’s disease. A neurologist can evaluate your symptoms and their severity and make a tentative diagnosis. One of the most common tests for Parkinson’s is to prescribe anti-Parkinson’s drugs for you to take and see if you respond to the medication. Most doctors consider a positive improvement of symptoms when you take medication to combat the symptoms to be positive proof that you have Parkinson’s disease.

Some doctors may order brain scans to help diagnose Parkinson’s disease. The brain scans can pick up abnormal brain patterns, but there are no visible markers to determine if they’re due to Parkinson’s or some other disorder. As in Alzheimer’s disease, the only proof positive of Parkinson’s disease is one that can only be found during an autopsy – the presence of microscopic brain structures called Lewy bodies. Interestingly, forensics doctors have found Lewy bodies in many older adults without diagnosed Parkinson’s disease, leading some to believe that everyone would develop Parkinson’s if they lived long enough.

Evaluating Parkinson’s Disease

A neurologist typically will evaluate you for the five major symptoms of Parkinson’s disease – tremors, rigidity, bradykinesia, freezing and postural instability. Bradykinesia is slow movements, and postural instability suggests a loss of balance. Generally, if you have two of the five symptoms and one of them is either tremors or rigidity, the neurologist will make a diagnosis of Parkinsonism. If you have either tremors or rigidity alone, he’ll usually diagnose probable parkinsonism, and if you have either freezing, slow movements or bradykinesia, the diagnosis will be possible parkinsonism.

Eliminating Other Causes

One of the first things the doctor should do is rule out other possible causes. Medically induced parkinsonism isn’t uncommon, and since it was first discovered that some medications can cause symptoms similar to Parkinson’s disease, the list of those medications has continued to grow. If you’re under 50, he may want to run tests to be sure that you don’t have a metabolic disorder called Wilson’s disease which causes similar symptoms, but is caused by a problem in using copper in your body. He may decide to do an MRI, which can eliminate further possible causes for your symptoms before he makes a final diagnosis.

The ‘Stages’ of Parkinson’s Disease

Staging diseases is a concept borrowed from cancer terminology. It refers to how far the disease has advanced, and usually determines the best options for treatment. In Parkinson’s disease, there are five stages. Your doctor will discuss with you the various treatment options that make the most sense for the stage of Parkinson’s disease that you are diagnosed with.