Progression of dopamine transporter decline in patients with the Parkinson variant of multiple system atrophy: a voxel-based analysis of [123I]β-CIT SPECT
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We characterized the progression of dopamine transporter (DAT) decline in the striatum and extrastriatal regions including the midbrain and pons of patients with the Parkinson variant of multiple system atrophy (MSA-P) and compared longitudinally collected SPECT results with those in a cohort of patients with Parkinson's disease (PD).
Eight patients with MSA-P (age 60.4 ± 7.7 years, disease duration 2.4 ± 1 years, UPDRS-III motor score 39.7 ± 4.7), and 11 patients with PD (age 61.2 ± 6.4 years, disease duration 2.4 ± 1.1 years, UPDRS-III motor score 18.9 ± 7.6) underwent a baseline and follow-up [123I]β-CIT SPECT investigation within a time period of 1.3 years. Statistical parametric mapping (SPM) and a repetitive ANOVA design were used to objectively localize the decline in DAT availability without having to make an a priori hypothesis as to its location.
SPM localized significant reductions in [123I]β-CIT uptake in the dorsal brainstem of MSA-P patients compared to PD patients (p < 0.001) at baseline. Additional reductions in the DAT signal were localized in the caudate and anterior putamen of patients with MSA-P patients compared to PD patients at the follow-up examination (p < 0.001). Relative decline in tracer binding was evident in the caudate and anterior putamen of MSA-P patients compared to PD patients in the longitudinal analysis (p < 0.05), whereas no significant relative signal alteration was observed in the brainstem.
In contrast to PD, the relatively higher rate of signal reduction in the caudate and anterior putamen is consistent with the faster disease progression reported in MSA-P. At baseline, the tracer uptake in the brainstem was already at very low levels in the MSA-P patients compared to that in healthy control subjects and did not progress any further, suggesting that the degeneration of monoaminergic neurons is almost complete early in the disease course.
KeywordsMultiple system atrophy Parkinson disease Dopamine transporter SPECT Voxel-by-voxel analysis
- 7.Brucke T, Asenbaum S, Pirker W, Djamshidian S, Wenger S, Wober C, et al. Measurement of the dopaminergic degeneration in Parkinson's disease with [123I]beta-CIT and SPECT. Correlation with clinical findings and comparison with multiple system atrophy and progressive supranuclear palsy. J Neural Transm Suppl. 1997;50:9–24.PubMedGoogle Scholar
- 13.Fahn S, Elton R. Unified Parkinson's disease rating scale. In: Fahn S, Marsden CD, Calne DB, Goldstein M, editors. Recent developments in Parkinson's disease. Vol. 2. Florham Park (NJ): Macmillan Health Care Information; 1987. p. 153–164.Google Scholar
- 24.Antonini A, Benti R, De Notaris R, Tesei S, Zecchinelli A, Sacilotto G, et al. 123I-Ioflupane/SPECT binding to striatal dopamine transporter (DAT) uptake in patients with Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy. Neurol Sci. 2003;24:149–50.PubMedCrossRefGoogle Scholar
- 28.Brooks DJ, Salmon EP, Mathias CJ, Quinn N, Leenders KL, Bannister R, et al. The relationship between locomotor disability, autonomic dysfunction, and the integrity of the striatal dopaminergic system in patients with multiple system atrophy, pure autonomic failure, and Parkinson's disease, studied with PET. Brain. 1990;1990:1539–52.CrossRefGoogle Scholar
- 43.Glover G, Pelc N. The nonlinear partial volume artefact. J Comput Assist Tomogr. 1979;25:79–86.Google Scholar
- 44.Hoffman EJ, Huang SC, Phelps ME. Quantification in positron emission tomography. 1. Effect of object size. J Comput Assist Tomogr. 1979;22:324–33.Google Scholar