The finding of a positive brain SPECT (single photon emission tomography) scan with dopamine transporter marker (DAT-SCAN) does not establish a diagnosis of Parkinson’s disease, which is instead based on the presence of clinical elements that meet the current diagnostic criteria. The test should therefore not be performed to confirm the diagnosis but may be required in selected cases for the differential diagnosis with non-neurodegenerative tremor syndromes where a diagnostic doubt exists. Similarly, myocardial scintigraphy with metaiodobenzylguanidine (MIBG) should not be used at the diagnostic stage but should be reserved in selected cases where there is a diagnostic uncertainty between Parkinson’s disease and another Atypical Parkinsonism (in particular, Multisystem Atrophy). In any case, special care is recommended when interpreting the results of a SPECT examination, considering that concomitant therapies (e.g., antidepressants) or pre-existing conditions (e.g., diabetes) could distort the examination. Positron Emission Tomography of the brain (PET) with various radionuclides (FDG, F-DOPA) is also not indicated for the diagnostic confirmation of Parkinson’s disease and should only be used if there is a diagnostic doubt to other diseases. None of the above tests is considered useful in assessing the progression of Parkinson’s disease to date. In general, the indication and interpretation of instrumental tests must therefore be considered in the context of each individual patient’s clinical history.

Download