Intrastromal corneal ring segments: effect of depth of implantation in visual, refractive, and topographic outcomes in patients with keratoconus.

Purpose: To evaluate visual, refractive, and topographic outcomes of intracorneal ring segment implantation in relation to the achieved segment depth, using the manual technique.

Setting: Ophthalmology Department, Hospital de Braga, Braga, Portugal.

Design: Retrospective cohort study.