I had a DAT scan in 2011 which confirmed my diagnosis as far as I was concerned. I seen the images that were produced from my scan and the depletion in cells was completely evident and left no doubt in my mind, nor that of my neurologist.
you have nothing to lose in having the scan, and do ask to see the images produced.
It seems standard fair too have the blood tests, the mri , and the nerve conduction testing, I had them all and many others have too to discount other illness's to arrive at where we are saying they are normal and a diagnosis we receive, the dat scan is the next tool to aid that diagnosis, 30% don't have a tremor.
Would you still have Questions in your mind un-answered if you don't have a dat scan? the scan itself is quite a simple affair a simple injection of an isotope, some waiting around away from pregnant mothers, and the scan not the same as a noisy MRI, I fell asleep during mine almost, the result will show the dopamine uptake into the brain, a lack of dopamine is what we suffer from and the result will be normal or abnormal.
I Saw mine briefly too Ali it looked abnormal to the eye and that was enough for me as well.
I don't know about meds affecting the datscan. I phoned the helpline before mine because I had some questions I needed answering about it and they were very patient and helpful. So please don't be hesitant about phoning the helpline, they are very good.
My datscan seemed normal but the movementent disorder specialist hasn't given up on me, my symptoms have been steadily growing worse and there is something clearly wrong so they are going to admit me into hospital for a few days (at some time still to be determined) to see if they can work it out. So try not to panic about results, you won't be cast aside if they are not as expected.
If your meds are helping your symptoms, then the neurologist must be on the right track. You will find a lot of people will advise worry and stress will make symptoms worse, so try not to worry too much, easier said than done, I know.
All the best