Assessment of visual impairment in patients with Alzheimer's disease.

We examined five patients with Alzheimer's disease who complained of poor vision. Two patients had mild Alzheimer's disease; they complained of problems with reading and of "bumping into things," yet both had normal visual acuities. One patient with moderate Alzheimer's disease had abnormal eye movements, visual-evoked potentials, and contrast sensitivity. The other two patients had severe Alzheimer's disease. Despite difficulties in performing the examination, we were able to see moderate impairments in visual acuity and visual fields, as well as marked dyschromatopsia, severe deficits in contrast sensitivity, and markedly abnormal eye movements and visual-evoked potentials.