My diagnosis came as a series of elimination I was diagnosed in 97. no MRI no CT scan just urine, blood and observations. My neurologist watched me walk, I did not swing my arms, I was so stiff especially my legs when walked it was very ridged, my knees didn't bend I walked like Frankinstien. After I was put in C/L 25/100 was like night and day. That has-been 25 yes ago, I am still on rhe same dosage that I started out on. Except I now take it every 3 hrs now instead of every 4 hrs. Plus I'm on the Neupro patches so now I only take a half of a C/L 25b/100. Other wise I will have dyskinesia.
Friends Susan

A DATscan is a MRI with a special dye. The shows how much dopamine is in your brain. A nice large tear drop is good= no Parkinson’s. Mine were small irregular circles = diagnosis = Parkinson’s. My movement specialist is a neurologist who specializes in movement disorders such as Parkinson’s, Essential Tremors, MS, Dystonia, etc. He tests my coordination, walking, reflexes and balance.

My husband was diagnosed 2 years ago based on his symptoms and then his response to carbidopa-levodopa. In his case, the symptoms were pretty classic: tremors, shuffling, hunched posture, balance issues, festinating. There was no need for a DaT scan. People whose symptoms are not clearly Parkinson's or who don't respond at all to c/l are more likely to have other tests to see if something else is going on like a stroke. His neurologist tests his strength and reflexes and balance every time we go in, but that is the only testing she has done. I have read that the accuracy of symptom based diagnosis is as good or better than the accuracy of a DaT scan. There are several people here who had DaT scans and their doctor's still weren't sure what was going on.

I have had PD for 8 years now and the only scans ive had were MRI’ S when I had the DBS operation.

My husband was diagnosed in 2014 with the same ridiculous test. He never had a tremor, ever. Sinemet led to muscle spasms in his thighs which they then labeled restless leg syndrome and said that was part of the progressive symptoms of PD. I call BS but no one listens. Each new drug causes new symptoms in his case. They just did a DATscan after 8 years! I don’t know if that is even valid after taking Carbidopa Levadopa for 8 years. No wonder that according to the Michael J Fox foundation at least 20%, or 1 in 5 people diagnosed with PD don’t have it.
Healthcare systems seem to create patients for life.