Combined laser refractory surgery and corneal crosslinking protocols in at-risk patients: current approaches and clinical results

Purpose: to systematize, based on the available scientific literature, the clinical and tomographic criteria for selecting patients at increased risk of corneal ectasia and to summarize the refractive, visual, and topographic outcomes of combined laser vision correction protocols (PRK-Xtra and LASIK-Xtra) performed in conjunction with corneal collagen cross-linking. Materials and methods. A search and analysis of publications was performed in the PubMed and PMC (NCBI) databases, as well as in specialized ophthalmological journals, using the keywords «PRK-Xtra,» «LASIK-Xtra,» «combined corneal cross-linking and refractive surgery,» «prophylactic corneal cross-linking,» «keratoconus suspect PRK,» and «simultaneous topography-guided PRK and CXL». The analysis included retrospective and prospective cohort studies, a randomized controlled trial, and clinical case series. Results. Combined protocols demonstrated stable refractive, visual, and topographic outcomes over 12 months to 5 years of follow-up. No clinically significant increase in intraocular pressure or progression of ectasia was observed in the studied groups. Several studies reported a small hyperopic shift in refraction compared with isolated laser ablation. Conclusion. PRK-Xtra and LASIK-Xtra may be considered in carefully selected patients at increased risk of corneal ectasia. However, the limited number of prospective studies, heterogeneous patient selection criteria, and variations in cross-linking parameters preclude definitive conclusions regarding the advantages of combined protocols over isolated laser vision correction.

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