Outcome of Keraring Intrastromal Corneal Ring Segment Implantation for the Management of Keratoconus

Objective: To report the outcome of Keraring intrastromal corneal ring segment implantation using mechanical tunnel creation method for the management of keratoconus. Patients and Methods: This study was conducted during the period from July 2009 to November 2011 at Dhahran Eye Specialist Hospital, Dhahran, Saudi Arabia. It included 38 patients (40 eyes) with keratoconus who underwent Keraring implantation using mechanical method for tunnel creation. Patients who had intraoperative or postoperative complications and/or did not complete at least 6 months of follow-up were excluded. All patients underwent complete ophthalmologic examinations that included measurement of the Uncorrected Visual Acuity (UCVA), Best Corrected Visual Acuity (BCVA), and keratometry before and 1 day, 1 week, 1 month, and 6 months after surgery. The ring segments were chosen based on a nomogram from the manufacturer. Results: The mean UCVA significantly improve from 0.9 LogMAR (20/160) to 0.5 LogMAR (20/60) ( p<0.001). The BCVA significantly improved on first postoperative day and remained stable until 6 months follow-up (p<0.001). The decrease in mean keratometry readings and astigmatism postoperatively was statistically significantly ( p<0.001). Conclusions: In the short term, intrastromal implantation of Kerarings significantly increases UCVA and BCVA in patients with keratoconus and significantly decreases keratometric values and astigmatism.