Corneal CXL With Hypo-osmolar Riboflavin Solution Versus Transepithelial CXL for Keratoconus With Thin Corneas
Narrative Responses:
Purpose
To compare efficiency and safety of corneal collagen cross-linking with hypo-osmolar riboflavin solution (HyCXL) versus transepithelial cross-linking (TE-CXL) for progressive keratoconus with thin corneas.
Methods
Patients with progressive keratoconus and a corneal thickness (CT) less than 400µ (without epithelium) were included in this study. Uncorrected distance visual acuities (UDVA) and corrected distance visual acuities (CDVA), biomicroscopic findings, intraocular pressure measurements, fundoscopic findings, pachymetric measurements and corneal topography parameters were recorded for each patient.There are 14 patients,20 eyes(mean age, 17.5±2.4 years) in the HyCXL group and 12 patients,18 eyes(mean age, 17±3.2years) in the TE-CXL group.
Results
In the HyCXL group improvement at month 9 was present for Kmax [-1.21 D, p = 0.01], Kmin (-1.42 D, p = 0.01) and mean K(-1.35D,P=0.01). The difference between preoperative-postoperative UDVA (p=0.24) and preoperative-postoperative CDVA was not significant (p=0.38). In the TE-CXL group improvement at month 9 was present for Kmax (-1.18 D, p = 0.01), Kmin (-1.54 D, p = 0.01) and mean K (-1.33 D, p = 0.01). The difference between preoperative-postoperative UDVA (p=0.22) and preoperative-postoperative CDVA was not significant (p=0.34). Changes at month 9 from baseline were not significantly different between the 2 groups (p= 0.15).
Conclusion
In thin corneas with progressive keratoconus, transepithelial cross-linking was less painful, provided similar effectiveness and fewer complications than cross-linking with hypo-osmolar riboflavin solution at 9-month follow-up.
Key Words: Keratoconus, transepitel collagen cross-linking, hypo-osmolar riboflavin solution