Pupillary response to tropicamide in Japanese patients with alcoholic dementia, Alzheimer's disease, and vascular dementia

The anticholinergic agent tropicamide causes a significantly greater change in the pupil diameter of patients with Alzheimer's disease (AD) than in that of patients with alcoholic or vascular dementia or in normal controls. Although the response increases with the severity of AD, the overlap of response with normal controls in milder cases and the difficulty of obtaining results in severe cases limit its use as a diagnostic tool.