Is there a role for DAT-SPECT imaging in a specialty movement disorders practice?

Abstract

Objective: Analyze indications for ordering DAT-SPECT scans and the clinical impact of scan results on patients evaluated in a movement disorders practice. Background: DAT-SPECT is FDA approved to evaluate cases of suspected presynaptic dopaminergic deficiency. Little data is available on clinical use and impact of these scans among movement disorders neurologists. Methods: DAT-SPECT scans ordered at the Northwestern University Parkinson's disease (PD) and movement disorders center from 2011-2013 were reviewed. Clinic notes were reviewed for information regarding the indication for ordering each scan, and to assess for any changes in clinical impression or management choices that followed the scan. Results: 83 scans were ordered by four specialists. Scans were commonly ordered to differentiate PD from Essential Tremor (21.7%, n = 18) or from drug-induced parkinsonism (21.7%, n = 18). In 59% (n = 49) of cases, a change in clinical diagnosis or medication regimen occurred within one visit after the scan. The strongest impact was seen for the indication of ET vs. PD in which 72.2% (n = 13) had a change in diagnosis, management, or both. Conclusions: Diagnostic uncertainty in cases of parkinsonism exists even in a tertiary referral center. DAT-SPECT has significant impact on clinical diagnosis and management even in the hands of movement disorders specialists.