Aging Change of Pupil Size in Normal and Diabetic Patients

ABSTRACT

It is well recognized that diabetic patients have small pupil. The most likely cause of the abnormally small pupil in diabetics is decreased funcitor of the autonomic nerves. We measured pupil size in 141 control subjects and 53 diabetic patients (29 cases with symptomatic autonomic neuropathy, 24 cases without symptomatic autonomic neuropathy) with portable pupillometry, PUPILSCAN in darkness. Pupils become smaller in healthy and diabetic subjects with advancing age. (log pupil size = 2.05 - 0.066 X age, r -0.47, padult). Although pupil size in diabetic patients without symptomatic autonomic neuropathy is not siginificantly smaller than in normal, pupil size in 28 of 29 diabetic patients with symptomatic neuropathy is beyond normal confidence interval and significantly decreased than in normal, Im 3 of 24 cases without symptomatic autonomic neuropathy, pupil size is decreased beyond normal confidence interval. It is believed that measurement of pupil size may be useful for early diagnosis in the diabetic autonomic neuropathy.