An unusual coexistence of iris mammillations and optic disc pit with keratoconus: A case report and literature review

Abstract

Iris mammillations are distinctive uniform nipple-like elevations that cover the anterior surface of the iris partially or totally. It is a rare finding and may coexist with other ocular and extraocular manifestations. Optic nerve pit (ONP), also known as optic disc pit (ODP) or optic hole, is a congenital defect resulting from the failure of fetal fissure closure during the embryonic development. It belongs to the congenital cavitary anomalies spectrum. This case presents a 19-year-old female patient who complained of a gradual decrease in visual acuity in both eyes for 4 years. Slit-lamp and fundus examinations revealed iris mammillations and ODP in the left eye. Corneal topography revealed bilateral keratoconus, which was managed with cross-linking. Iris mammillations and ODP are poorly understood ocular anomalies that are not reported frequently and have never been reported previously both combined with keratoconus. Thus, ophthalmologists should be aware of these conditions, their differential diagnosis, and their possible association with other disorders. This is the first reported case of the combined coexistence of iris mammillations and ODP with keratoconus.