Relation of 18-F-Dopa PET with hypokinesia-rigidity, tremor and freezing in Parkinson’s disease

• Main Authors: Angelina R.A. Pikstra, Anouk van der Hoorn, Klaus L. Leenders, Bauke M. de Jong
• Format: Article
• Language: English
• Published: Elsevier 2016-01-01
• Series: NeuroImage: Clinical
• Subjects: Parkinson's disease; F-Dopa PET; Hypokinesia; Rigidity; Tremor
• Online Access: http://www.sciencedirect.com/science/article/pii/S2213158216300092

Introduction: In this retrospective study concerning patients with Parkinson's disease (PD) scanned with 18-F-Dopa PET (N = 129), we looked for an association between reduced 18-F-Dopa uptake and the key PD symptoms tremor and hypokinesia-rigidity. We hypothesized to find a stronger correlation between dopaminergic depletion in the striatum and hypokinesia-rigidity compared to tremor. Methods: The onset side of symptoms (documented for 102 patients) as well as the first registered UPDRS (available for 79 patients) was used to correlate with F-Dopa uptake values in the caudate nucleus and putamen in this large retrospective sample. Results: Reduced F-Dopa uptake was contralateral to hypokinesia-rigidity symptoms and correlated with its severity (quantified by UPDRS). For tremor severity, no correlation was seen with F-Dopa reduction. Furthermore, freezing of gait correlated with reduced F-Dopa uptake in the putamen of the right hemisphere. Conclusion and discussion: Our results, obtained in a large patient group, provides support for the concept that tremor in PD is not only based on a dopamine related pathway but may rely on a different pathway.