OBJECTIVE: To determine whether technetium-99m-labeled tropane derivative single-photon emission computed tomography (^99mTc-TRODAT-1 SPECT) provides results comparable to those of the less widely available, less accessible tool fluorine-18-labeled fluorodopa positron-emission tomography (¹⁸F-FDOPA PET) in the setting of a movement disorders clinic. MATERIALS AND METHODS: In this prospective pilot study, eight subjects with a clinical diagnosis of Parkinson’s disease were randomly selected from among patients under treatment at a movement disorders clinic and submitted to ^99mTc-TRODAT-1 SPECT and ¹⁸F-FDOPA PET. The results were read by two experienced observers, and a semiquantitative analysis was performed. RESULTS: The visual and semiquantitative analyses were concordant for all studies, showing that radiotracer uptake in the contralateral striatum on the most affected side was lower when ^99mTc-TRODAT-1 SPECT was employed. The semiquantitative analysis demonstrated a significant correlation between ¹⁸F-FDOPA PET and ^99mTc-TRODAT-1 SPECT (r = 0.73; p < 0.01). CONCLUSION: It appears that ^99mTc-TRODAT-1 SPECT is a valid option for the study of dopaminergic function in a clinical setting.

Keywords: Parkinson disease/diagnostic imaging; Parkinsonian disorders/diagnostic imaging; Tomography, emission-computed, single-photon/methods; Positron-emission tomography/methods; Tropanes/pharmacokinetics; Dihydroxyphenylalanine/analogs & derivatives.