An FP-CIT PET comparison of the difference in dopaminergic neuronal loss in subtypes of early Parkinson's disease. (April 2014)

• Record Type: Journal Article
• Authors: Song, In-Uk; Chung, Yong-An; Oh, Jin-Kyoung; Chung, Sung-Woo
• Is Part Of: Acta radiologica. Volume 55:Number 3(2014:Apr.)
• Page Start: 366
• Page End: 371
• Publication Date: 2014-04
• Subjects: Parkinson's disease -- tremor -- FP-CIT PET -- nigrostriatal dopaminergic system; Radiology, Medical -- Periodicals; Radiography, Medical -- Periodicals; Radiotherapy -- Periodicals; 616.0757
• DOI: 10.1177/0284185113498075
• Languages: English
• ISSNs: 0284-1851

Abstract

Background: Patients with tremor-dominant Parkinson's disease (PD) have slower disease progression, show less cognitive decline, and have more favorable outcomes than patients with non-tremor PD. However, the pathophysiology of PD tremor remains unclear. Whether there are differences in nigrostriatal dopaminergic dysfunction between the two PD subtypes is unknown. Purpose: To evaluate the differences in regional dopamine transporter (DAT) density in the brain between different subtypes of early PD using FP-CIT PET/CT. Material and Methods: We recruited 43 patients with PD (21 tremor-dominant PD [TP] and 22 non-tremor-dominant PD [NTP]) and 18 age-matched healthy controls. All patients with PD underwent FP-CIT PET/CT imaging and evaluated Parkinsonian motor severity by using the Hoehn and Yahr stage and Part III of the Unified Parkinson's Disease Rating Scale (UPDRS). We also compared tremor and non-tremor symptoms with motor phenotype scores between two subtypes of PD. Results: All patients with PD demonstrated a significantly decreased FP-CIT uptake in the putamen compared to healthy controls. Differences in putamen FP-CIT uptake versus caudate nucleus FP-CIT uptake in PD showed putamen uptake was significantly more impaired than that in the caudate nucleus. However, there was no significant difference in FP-CIT uptake in the striatum between both PD groups at the same early stage of disease. Conclusion: We suggest that differential of DAT uptake in the striatum did not allow for a reliable separation of subtypes into tremor-dominant and non-tremor-dominant, especially in the early stages of PD. Therefore, we assumed that many systems besides the nigrostriatal dopaminergic system are involved in the generation of tremors in PD.