Clinical and Topographical Corneal Changes after Keraring Implantation in Keratoconus Patients

Mirzaei Mohamad, Najafi Amin, Shahraki Kurosh, Taheri Nazli, Mirzaei Samira


Introduction: Keratoconus is a progressive, non-inflammatory, bilateral, ecstatic disease of the cornea that is characterized by corneal steepening which progresses to irregular conical shape, with subsequent irregular astigmatism and decreased visual acuity. In early stages of disease, spectacles or RGP lenses are the main treatment. At advanced stages, when these treatment options fail to correct visual acuity, surgical procedures such as penetrating keratoplasty or lamellar keratoplasty are required.

METHODS: Keraring segments were placed in 30 eyes of 21 keratoconus patients. The mean follow-up time was 6.2 months. All patients underwent a complete ocular examination and corneal topography which was obtained by Pentacam (Oculus Pentacam®, USA). Improvement in uncorrected visual acuity (UCVA), best spectacle corrected visual acuity, refraction and topographic changes including keratometry, maximum anterior and posterior elevation, central corneal thickness and thinnest point thickness and location were evaluated.

RESULTS: No intraoperative or postoperative complications occurred in any of the patients. ICRS implantation significantly improved UCVA (P=0.005) and BSCVA (P=0.000). Mean Spherical equivalent significantly reduced from -6.66±3.52 to -4.42±3.20 (p=0.000). A clinically significant reduction in mean keratometry (p=0.000), Max Ant Elevation (P=0.024) and Max Post Elevation (P=0.002) were recorded. No clinically significant changes in central corneal thickness, thinnest point thickness and thinnest point location were observed.

Conclusion: With mean follow-up of 6.2 months, Keraring segments implantation caused significant clinical improvement in UCVA, BCVA Refractive Error and Keratometric findings of the most keratoconic patients.


Keywords: keratoconus; ICRS; Keraring

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