Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Randomized Controlled Trial
. 2023 Sep;71(9):3210-3218.
doi: 10.4103/IJO.IJO_2557_22.

Ten-year follow-up of corneal cross-linking and refractive surface ablation in patients with asymmetric corneal topography

Bernardo Kaplan Moscovici  1 , Pablo Felipe Rodrigues, Marcos Paulo Suehiro Dantas, Juliana Taemy Okimoto, Obidulho Sakassegawa Naves, Felipe Marques de Carvalho Taguchi, João Baptista Nigro Santiago Malta, Mauro Campos
Affiliations
Randomized Controlled Trial

Ten-year follow-up of corneal cross-linking and refractive surface ablation in patients with asymmetric corneal topography

Bernardo Kaplan Moscovici et al. Indian J Ophthalmol. 2023 Sep.

Abstract

Purpose: Compare the safety and efficacy of wavefront-guided photorefractive keratotomy (PRK) 6 months after cross-linking (CXL) to wavefront-guided PRK alone for refractive correction in patients with bilateral asymmetric corneal topography.

Methods: Prospective randomized clinical trial with 16 patients (32 eyes). CXL with subsequent PRK after 6 months in one eye, and PRK alone was performed in contralateral eyes. The follow-up was 10 years. We analyzed visual outcomes, Scheimpflug topography, and corneal haze evaluation.

Results: Eyes in the PRK group showed better results than in the CXL + PRK group. Mean postoperative CDVA was 0.044 logmar (SD, 0.073) in the PRK group and 0.1 logmar (SD, 0.21) in the CXL + PRK group, the mean sphere was + 0.21 (SD, 0.6) D in the PRK group and 0.87 (SD, 2.3) D in the CXL + PRK group, and mean SE was -0.35 (SD, 0.65) D in the PRK group and 0.62 (SD, 2.32) D in the CXL + PRK group. In one patient, a steepening of 2.5 D and a thinning of 17 μm occurred in PRK alone group. Two patients in the CXL + PRK group presented corneal haze. The overall complication rate was 18,75% (haze and ectasia).

Conclusion: Non-simultaneous CXL and PRK procedures yielded good refractive results, but worse than those obtained with PRK alone. Although one patient in the PRK group developed corneal ectasia, the CXL + PRK group had a higher loss of vision lines, indicating less safety.

Keywords: Cornea; corneal stroma; corneal topography; excimer; lasers; photorefractive keratectomy; refractive surgery.

PubMed Disclaimer

Conflict of interest statement

None

Figures

Figure 1
Figure 1
(A) Refractive results of CXL + PRK group (CXL+ PRK). (B) Refractive results of PRK group (PRK). (a) Uncorrected distance visual acuity. (b) Difference between uncorrected and corrected distance visual acuity. (c) Change in corrected distance visual acuity. (d) Refractive astigmatism. (e) Spherical equivalent refraction accuracy. (f) Spherical equivalent refraction stability
Figure 2
Figure 2
Corneal topography of three patients with postoperative complications. (a) (first row: preoperative; second row: postoperative)—Corneal ectasia. The right eye only performed PRK and the left eye PRK + CXL. (b) (first row: preoperative; second row: postoperative)—Corneal haze, developed only in the PRK + CXL eye (OS). (c) (first row: preoperative; second row: postoperative)—Corneal haze, developed only in the PRK + CXL eye (OD). The third image in the second row shows the postoperative corneal densitometry
Figure 3
Figure 3
(a and b) Preoperative corneal topography of all patients and inferior–superior asymmetry (3 mm zone)—Supplementary material
See this image and copyright information in PMC

References

    1. Dawson DG, Randleman JB, Grossniklaus HE, O'Brien TP, Dubovy SR, Schmack I, et al. Corneal ectasia after excimer laser keratorefractive surgery: Histopathology, ultrastructure, and pathophysiology. Ophthalmology. 2008;115:2181–91.e1. - PubMed
    1. Sorkin N, Kaiserman I, Domniz Y, Sela T, Munzer G, Varssano D. Risk assessment for corneal ectasia following photorefractive keratectomy. J Ophthalmol 2017. 2017:2434830. - PMC - PubMed
    1. Randleman JB, Trattler WB, Stulting RD. Validation of the ectasia risk score system for preoperative laser in situ keratomileusis screening. Am J Ophthalmol. 2008;145:813–8. - PMC - PubMed
    1. Randleman JB, Woodward M, Lynn MJ, Stulting RD. Risk assessment for ectasia after corneal refractive surgery. Ophthalmology. 2008;115:37–50. - PubMed
    1. Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol. 2003;135:620–7. - PubMed

Publication types