Intraestromal Corneal Ring in Mild Keratoconus

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.