Author response: Autopsy validation of 123 I-FP-CIT dopaminergic neuroimaging for the diagnosis of DLB

Professor Abe raises the important issue of the involvement of Lewy body disease in the substantia nigra (SN) when making the diagnosis of dementia with Lewy bodies (DLB). It has long been known that, even later on in their illness, about 25% of patients with DLB do not show features of parkinsonism. This is recognized in the consensus criteria for DLB, which do not require parkinsonism for diagnosis. Patients with DLB can have normal dopaminergic imaging because, as with our 3 patients who also had no parkinsonism,1 there is no significant involvement of the SN by Lewy body disease.