Congenital aplasia of the iris sphincter and dilator muscles.

Congenital aplasia of the iris sphincter and dilator muscles is rare. We describe a 3-month-old boy with a patent ductus arteriosus who had this anomaly, with no other ocular or systemic abnormalities. The child, whom we followed for over 7 years, had reduced accommodative amplitudes. This anomaly, although it bears some similarity to Gillespie's syndrome, circumpupillary aplasia and aniridia, is an isolated, nonprogressive condition that general physicians need to differentiate from the neurologically dilated pupil so that misdirected, unnecessary investigations can be avoided.