Neuroretinal function is normal in early dementia of the Alzheimer type

We recently demonstrated that retinal ganglion cell function, optic nerve h ead parameters and the retinal nerve fiber layer thickness are not altered in early dementia of the Alzheimer type: (DAT). Our current objective was t o assess whether the function of cells located more distally in the retina is also unaffected by the disease. We evaluated 23 individuals with early t o moderate DAT and 23 healthy age-matched subjects. all displaying clinical ly normal visual function. Scotopic and photopic flash electroretinograms ( fERGs) and oscillatory potentials (OPs) were recorded. The amplitude and la tency of the retinal potentials did not differ between DAT and control subj ects. Our current results showing normal fERGs and OPs in early DAT indicat e that the underlying neurons giving rise to these signals are not impaired by the disease process. These data support and extend our recent findings suggesting that visual deficits in DAT do not stem from neuroretinal dysfun ction. (C) 2001 Elsevier Science inc. All rights reserved.