06/03/2026
.ets .ets Title: Effects of Riboflavin-UVA Corneal Collagen Cross-Linking on Corneal Sensitivity and Ocular Surface Parameters
Purpose:
To review the effects of riboflavin-UVA corneal collagen cross-linking (CXL) on corneal sensitivity, corneal nerve regeneration, and dry eye parameters.
Methods:
A review of the current literature evaluating changes in corneal sensitivity, subbasal nerve plexus morphology, and ocular surface parameters after CXL performed for keratoconus and corneal ectasia.
Results:
Several studies have demonstrated a transient reduction in corneal sensitivity during the early postoperative period following epithelium-off CXL, mainly related to epithelial removal and temporary damage to the subbasal nerve plexus. Sensitivity typically begins to recover within 3–6 months and may return to baseline levels within the first postoperative year. In vivo confocal microscopy studies have shown a reduction in subbasal nerve density immediately after treatment, followed by gradual nerve regeneration over time. Some recent reports have also described improvements in ocular surface parameters, including reduced Ocular Surface Disease Index (OSDI) scores, increased tear break-up time (TBUT), and decreased inflammatory markers such as MMP-9 in the tear film during follow-up.
Conclusions:
Although corneal collagen cross-linking is primarily indicated for the treatment of keratoconus, available evidence suggests that corneal sensitivity generally recovers after an initial postoperative reduction, and some patients may experience secondary improvements in ocular surface parameters. However, further studies are needed to clarify the relationship between CXL, corneal nerve regeneration, and dry eye disease.
Luigi Marino MD PhD
Medico Chirurgo
Specialista Clinica Oculistica