Optic nerve head and nerve fiber layer in Alzheimer's disease

We compared (1) the differences in the retinal nerve fiber layer between 26 patients with Alzheimer's disease and 30 age- and race-matched normal controls with use of blue-light high-resolution photography, (2) the differences in disc pallor between 30 patients with Alzheimer's disease and 32 controls with use of a boundary-tracking program and fundus photographs, and (3) the topographic disc variables between 26 patients with Alzheimer's disease and 36 controls with use of an optic nerve head analyzer. A higher proportion of patients with Alzheimer's disease had detectable nerve fiber damage as seen by red-free photography compared with controls. Although the pallor area-to-disc area ratio was not significantly different between patients with Alzheimer's disease and controls, the patients with higher pallor area-to-disc area ratios had higher Alzheimer's Disease Assessment Scale (ADAS) scores and longer durations of disease. Patients had an increased cup-to-disc ratio and cup volume and decreased disc rim area compared with controls. These variables also correlated significantly with ADAS scores and the duration of disease. The correlation among the optic nerve head changes and the ADAS scores in patients with Alzheimer's disease suggests a potential role for optic nerve head analysis in monitoring the progression of Alzheimer's disease and in assessing the effectiveness of any treatments developed.