123I-Ioflupane SPECT in the diagnosis of suspected psychogenic Parkinsonism.

Psychogenic Parkinsonism (PsyP) can be clinically difficult to differentiate from Parkinson's disease (PD). Striatal dopamine transporter (DAT) imaging could be helpful in differentiating them. We performed (123)I-Ioflupane single-photon emission computed tomography (SPECT) in 9 patients with suspected PsyP. In 1 patient, (123)I-Ioflupane SPECT disclosed bilateral decrease of striatal tracer uptake that indicated nigrostriatal degeneration. In this patient, a parkin gene mutation was detected. In the other 8 patients, (123)I-Ioflupane SPECT was normal and supported the initial suspicion of PsyP. Normal DAT imaging supports the diagnosis of PsyP, whereas reduced striatal tracer uptake suggests an underlying neurodegenerative Parkinsonism and should encourage the search for additional causes for the syndrome.