Role of dopamine transporter imaging in routine clinical practice.
Functional imaging of the dopamine transporter (DAT) defines integrity of the dopaminergic system and has its main clinical application in patients with mild, incomplete, or uncertain parkinsonism.
Imaging with specific single positron emission computerized tomography ligands for DAT is a marker for presynaptic neuronal degeneration.
Uptake correlates with disease severity, in particular bradykinesia and rigidity.
Helps monitor progression of disease.
Imaging is abnormal in idiopathic Parkinson’s disease, multiple system atrophy and progressive supranuclear palsy but does not distinguish between these disorders.
Dopamine loss is seen in the earliest clinical presentations of true parkinsonism.
A normal dopamine transporter scan suggests an alternative diagnosis such as essential tremor, vascular parkinsonism, drug-induced parkinsonism, or psychogenic parkinsonism.