Anterograde Degeneration of the Nigrostriatal Pathway Visualized by 123I-FP-CIT SPECT in a Patient With Artery of Percheron Infarction.

I-FP-CIT SPECT is widely used for diagnosis in patients with parkinsonism. Vascular parkinsonism usually has nonspecific findings from normal uptake to radiotracer decrease in the infarcted region. Infarction of the substantia nigra has been reported as a rare cause of vascular parkinsonism. We present a case of artery of Percheron infarction involving the substantia nigra unilaterally with ipsilateral reduction of striatal uptake on I-FP-CIT SPECT, suggesting anterograde degeneration of the nigrostriatal pathway. Infarction of the substantia nigra should be considered in cases of decreased striatal uptake with marked laterality on I-FP-CIT SPECT.