Efficacy and safety of PTK and PRK combined with CXL on post-LASIK keratectasia

Abstract

Objective To evaluate the efficacy and safety of phototherapeutic keratectomy (PTK) and photorefractive keratectomy (PRK) combined with corneal collagen cross-linking (CXL) in preventing the progression of post-laser-assisted in situ keratomileusis (LASIK) keratectasia. Methods In this prospective, self-controlled study, 16 eyes of 14 patients with post-LASIK keratectasia underwent PTK and PRK combined with CXL procedures. None of the 14 patients had keratoconus before LASIK. The main outcomes were measured and recorded at baseline and at months 1, 3, and 6 after LASIK. The measured parameters included logarithm of the minimum angle of resolution (LogMAR) of the uncorrected visual acuity (UCVA), LogMAR of the best-corrected visual acuity (BCVA), central corneal thickness (CCT), maximum front keratometry (Kmax), and endothelial cell density (ECD). Data were analyzed using Wilcoxon rank sum test. Results PTK and PRK combined with CXL appeared to halt the progression of post-LASIK keratectasia without apparent complications. LogMAR UCVA improvements were statistically significant (P<0.01) at 1, 3, and 6 months postoperatively (M=0.10, 0.10, and 0.00, respectively). There was also a significant reduction in Kmax (P<0.05) at postoperative months 1, 3 and 6. At 6 months after surgery, M of CCT was decreased (P<0.01). There were no significant changes in LogMAR BCVA or ECD during 6 months of follow-up. Conclusion PTK+PRK+CXL is effective and safe in treating post-LASIK keratectasia. Without apparent complications, it can improve UCVA and reduce Kmax after surgery. Key words: Corneal collagen cross-linking; Keratectasia; Phototherapeutic keratectomy; Photorefractive keratectomy; Refractive reconstruction