Cardiac I-123-meta-iodobenzylguanidine (MIBG) uptake in dementia with Lewybodies: comparison with Alzheimer's disease

Cardiac I-123-meta-iodobenzylguanidine (MIBG) uptake was measured in 11 pat ients with dementia with Lewy bodies (DLB), 10 patients with Alzheimer's di sease (AD), and 10 age matched control subjects. The severity of cognitive impairment and duration of symptoms in patients with DLB matched that in th e patients with AD. The heart/mediastinum (H/M) ratio of MIBG uptake in the patients with AD was indistinguishable from that in the control subjects. However, the HIM ratio in all patients with DLB was significantly lower tha n that in the patients with AD and control subjects (p <0.001). These findi ngs indicate that local myocardial sympathetic nerves are affected in DLB a nd that cardiac I-123-MIBG scintigraphy may provide a means of differentiat ing DLB from AD.