PET Radioligands Reveal the Basis of Dementia in Parkinson's Disease and Dementia with Lewy Bodies.

PET Radioligands Reveal the Basis of Dementia in Parkinson's Disease and Dementia with Lewy Bodies. Neurodegener Dis. 2016;16(1-2):118-124 Authors: Gomperts SN, Marquie M, Locascio JJ, Bayer S, Johnson KA, Growdon JH Abstract BACKGROUND: Effective therapies for dementia with Lewy bodies (DLB) and Parkinson's disease (PD) dementia will require accurate diagnosis and an understanding of the contribution of distinct molecular pathologies to these diseases. We seek to use imaging biomarkers to improve diagnostic accuracy and to clarify the contribution of molecular species to cognitive impairment in DLB and PD. SUMMARY: We have performed cross-sectional and prospective cohort studies in subjects with DLB, PD with normal cognition, PD with mild cognitive impairment and PD with dementia, contrasted with Alzheimer's disease (AD) and healthy control subjects (HCS). Subjects underwent formal neurological examination, detailed neuropsychological assessments, MRI and PET scans with the radioligands altropane (a dopamine transporter, DAT) and Pittsburgh compound B (PiB; β-amyloid). Putamen DAT concentrations were similar in DLB and PD and differentiated them from HCS and AD. Decreased caudate DAT concentration related to functional impairment in DLB but not PD. PiB uptake was greatest in DLB. However, cortical PiB retention was common in PD and predicted cognitive decline. PET imaging of tau aggregates holds promise both to clarify the ...
Source: Neuro-Degenerative Diseases - Category: Neurology Authors: Tags: Neurodegener Dis Source Type: research