SLC6A3 and Parkinson disease: Distribution volume ratio (DVR) and binding ratio (BR), measures of DAT uptake capacity, were measured by analyzing clinical 123I-FP-CIT SPECT images of 29 patients with dNDD, including dementia with Lewy bodies and Parkinson’s disease, and 18 patients with non-dNDD, using Montreal Neurological Institute space-based anatomical standardization and an atlas template, which utilizes statistical parametric mapping.