Visual and refractive outcomes of combined excimer laser ablation with accelerated corneal collagen cross-linking in subclinical keratoconus

Abstract

Purpose: The purpose of the study was to evaluate efficacy, safety, and stability of visual and refractive outcomes of combined photorefractive keratectomy (PRK) with accelerated corneal collagen cross-linking (CXL) in subclinical keratoconus. Materials and Methods: This retrospective study included 140 eyes (75 patients) with subclinical keratoconus which underwent simultaneous topography-guided PRK with acceleratedCXL (2.7 J/cm2). Outcome measures were pre- and postoperative uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), manifest refraction, and keratometry. Results: Refractive and keratometric parameters demonstrated statistically significant improvement from baseline to postoperative 12 months. UDVA of ≥20/20 was achieved in 90.7% (127/140) eyes and ≥20/40 in 96.4% (135/140) eyes at last follow-up. Regarding refractive outcomes, 94.3% (132/140) eyes were within ± 1.00 D of attempted refractive correction and 82.9% (116/140) eyes had astigmatism of ≤0.25D postoperatively as compared to 22.9% (32/140) eyes at preoperative levels. Regarding safety, 90.7% (127/140) eyes maintained their preoperative CDVA and 7.2% (10/140) eyes lost ≥2 lines of CDVA. Complications included corneal haze in 7.14% (10/140) and corneal ectasia in 0.7% (1/140) eyes. Conclusion: During the 12-month follow-up, combined topography-guided PRK and accelerated CXL provided good visual and refractive outcomes offering spectacle independence in subclinical keratoconus eyes; however, development of one case of ectasia (0.7%) indicates compromised safety and seems to suggest that utilizing 2.7 J/cm2 energy for CXL procedure may not be adequate.