Pupil responsiveness in diabetes mellitus

The authors compared pupil responsiveness to light, convergence, and the effects of topical cocaine 4%, epinephrine 1%, phenylephrine 1%, homatropine 10%, and pilocarpine 1% in a group of 62 diabetics with a sex- and age-matched group of normal subjects. The duration of disease, metabolic control, and type of diabetes mellitus, the presence and severity of diabetic retinopathy, and evidence of systemic vegetative neuropathy were considered. It was found that sympathetic denervation was related significantly to the duration of disease and to the development of systemic autonomic neuropathy. There were also signs of iris myopathy in the pupil alterations of long-standing diabetics, explaining the poor pupil responsiveness to mydriatics occasionally found in these patients. Pupillary autonomic diabetic neuropathy should be considered an early and major sign of the development of systemic vegetative diabetic disease.