Welcome to HealingWell.
There is no definitive test for Parkinson's. It's a matter of eliminating certain things, then meeting certain criteria. I should preface all this by saying that no two people with Parkinson's are the same. We each have different combination of symptoms. We each respond differently to medications. We each progress at a different rate. I recently heard a neurologist say he thinks Parkinson's is really 20 different diseases - not one.
An MRI eliminates a brain tumor. A CT Scan eliminates stroke. Blood tests eliminate multiple things. An eye exam can eliminate certain things. Once those are eliminated, it's a matter of observation - meeting 4 or more items such as arm swing (do both arms swing equally or does one arm swing less than the other), gait (is your stride/step equal or do you tend to 'drag' one leg/foot), etc. If you display 4+ of the items, then the diagnosis is often Parkinson's.
There is something called a PET scan that can be used when diagnosing PD. It's expensive and not really considered a feasible tool for diagnosis.
Sometimes doctors will have a patient take a PD medication called Sinemet for a few days or weeks.. If the patient responds favorably to Sinemet, it's often an indication of Parkinson's. (Sinemet is the gold standard - works the best. However, there are potential side effects that continue to worsen with time so read up on t0hem before making a decision to take Sinemet long term.)
I hope this helps. Keep us informed of your progress. Best of luck!
Parkinson's Disease Moderator
Diagnosed with Parkinson's disease 2001. Meds: Requip XL 24mg, Amantadine 200 mg
Life is a dance. Don't sit it out. ---- Jackson H. Brown