Background: This study aimed to investigate the relationship between patterns of reduced cerebral blood flow (CBF) evaluated by means of 123 I-N-isopropyl-p-iodoamphetamine ([ 123 I]IMP) scintigraphy and nonmotor symptoms in new-onset Lewy body disease (Parkinson's disease and dementia with Lewy bodies [DLB]). Material and methods: Twenty-four patients diagnosed with new-onset Parkinson's disease or DLB underwent [ 123 I]IMP CBF scintigraphy at St.