Clinical outcomes after intracorneal ring segment implantation for keratoconus management in corneas with mild apical haze

Purpose: The implantation of intracorneal ring segments represents an effective and safe therapeutic option for visual improvement in patients with keratoconus. The presence of corneal opacities is considered an exclusion criterion for this operation. Methods: This is a retrospective cohort study of six eyes of six keratoconus patients at Queen Victoria Hospital, East Grinstead, UK, between January 2012 and December 2016. Femtosecond laser-assisted intracorneal ring segment implantation was performed in six eyes with apical corneal haze. Preoperative and postoperative visual acuity, keratometry readings, as well as corneal pachymetry were compared at 6-month follow-up. Results: Uncorrected visual acuity (UCVA) [LogMAR] improved significantly from median 1.05 [95% confidence interval (CI): 0.83-0.13] preoperatively to 0.9 (95% CI: 0.63-1.00) at 6 months postoperatively (p = 0.03). Corrected visual acuity (CDVA) also improved significantly from median 0.75 (95% CI: 0.43-1.00) preoperatively to 0.4 (95% CI: 0.23-0.50) at 6 months postoperatively (p = 0.03). Keratometric readings, K-max (diopters) and K-mean (diopters), decreased significantly from 54.5 and 47.85 preoperatively to 53.45 and 46.42 postoperatively, respectively (p = 0.03). Corneal pachymetry showed no significant changes postoperatively. Conclusion: The results of this study show that the presence of apical haze should not exclude the implantation of intracorneal ring segments in patients with keratoconus.