Diagnosis
Neuroimaging
Often MRI or CT scans show only non–specific mild to moderate cerebral atrophy, but they may show specific abnormalities in Huntington’s disease (caudate atrophy) OPCA (atrophy of the Pons and cerebellum), increased signal intensity in the putamen on T2 weighted images, (multiple system atrophy). MRI and CT scan are particularly useful in suggesting non degenerative secondary causes of movement disorders, like cerebrovascular accidents abscesses and tumors as well as calcium deposition, carbon monoxide intoxication. SPECT scanning is useful in corticobasal gangalionic degeneration, where focal parietal lobe hypoactivity can sometimes be detected.

EEG
May show epileptiform discharges in paroxysmal dyskinesias and myoclonic disorders, tremors can be characterized with tremorometer recording while EMG may help in dystonias especially with botulinum injection therapy.

Fluid and tissue analysis
Apart form basic electrolytes, CBC, LFT and TFTs, copper and serum ceruloplasmin levels are useful, as are fresh blood smears for neuroacabtgicttisus.

Neuropsychological tests
Are useful in making diagnoses of Huntingtion’s disease and Tourette syndrome, and also in guiding potential decisions regarding medication therapies.