Intrastromal Corneal Ring Segments (KeraRing(R)) Implantation for the Correction of Keratoconus

ABSTRACT

PURPOSE: To report the outcomes after the implantation of intrastromal corneal ring segments (KeraRing(R)) by manual tunnel creation for the correction of keratoconus. METHODS: The present retrospective case series was comprised of 12 eyes of 11 consecutive keratoconic patients. Intrastromal corneal ring segments (KeraRing(R)) were implanted for keratoconus correction after manual tunnel creation. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refractive outcome, and complete ophthalmologic examinations were performed before and after surgery at 1 day, 1 week, 3 months, and 6 months. Corneal topography was measured before surgery, 6 months after surgery and during any necessary follow-up visits. RESULTS: Intrastromal corneal ring segments (KeraRing(R)) implantation significantly increased BCVA from logMAR 0.47 +/- 0.19 to logMAR 0.28 +/- 0.17 (P < 0.05) and decreased the spherical equivalent from -6.03 +/- 3.24 D to -2.24 +/- 1.96 D. The simulated keratometric value in the Orbscan IIz significantly decreased in K maximum from 50.7 +/- 2.93D to 47.65 +/- 3.15 D and in K minimum from 47.65 +/- 3.15 D to 44.92 +/- 2.80 D. CONCLUSIONS: Intrastromal corneal ring segments implantation (KeraRing(R)) by manual tunnel creation appears to be effective in improving BCVA and reducing corneal astigmatism and keratometric value in keratoconic patients. KeraRing(R) may delay or prevent the need for a corneal graft, and reduce the contact lens intolerance.