A group of 65 patients with keratoconus who were implanted with an intrastromal corneal ring; the group was composed of 40 males (61.50%) and 25 females (38.50%), with a mean age of 27.88 ± 7.38 years (range, 17-47 years). The patients were fully informed about the study and signed a consent form previously approved by the ethics committee of our institution.

We used the Amsler-Krumeich classification and included only patients classified as grade I or II. The investigators performed the intraestromal corneal ring surgery in the selected group.

The patients underwent surgery to implant the intrastromal corneal ring (Ferrara Ophthalmics, Belo Horizonte, Brazil) using a manual technique. The procedures were performed by a single surgeon with extensive training in corneal surgery. All patients received the same ring, and the number (1 or 2 segments), thickness, and arc size were calculated using the nomogram provided by the manufacturer.

Wave front data

Uncorrected visual acuity

Best corrected visual acuity