Abstract
Purpose :
Corneal edema in acute keratoconus is caused by a sudden break of Descemet membrane. This study aims to assess whether pre-treatment with corneal crosslinking (CXL) can ameliorate corneal edema in a subsequent hydrops.
Methods :
Normal or keratoconic human tissue (obtained during penetrating keratoplasty; n=6 each) was incubated with Corneal Culture Medium (CCM) I for hydration for 1 day and then dehydrated with CCM II for 24 hours. Then either CXL with 30-minutes topical application of 0.1% riboflavin followed by a 30-minutes UVA irradiation (3mW/cm2) or riboflavin only (in controls) followed. Afterwards, tissues were incubated with CCM I and central corneal thickness was measured using OCT (before treatment: hydration, dehydration; after treatment: overnight, 1 day, 2 days, 4 days). In the vivo experiment, C57BL/6 mice received CXL or only riboflavin (controls). Fourteen days later, a linear perforating incision was performed as murine model of acute keratoconus. Corneal thickness was measured by OCT after incision at 15 and 30 minutes, 1 and 4 hours, 1, 7 and 14 days (thickness from 5 naïve mice as the baseline).
Results :
In the ex vivo experiments, crosslinked normal and keratoconic tissue had a significantly reduced swelling after rehydration: For normal corneas (normalized to “Dehydration”), the percentage of increase in thickness between Dehydration and 24 hours was 15.87% in the CXL group and 89.3% in controls (P=0.0019). For keratoconus corneas, results were 6.53% in CXL-treated and 38.2% in controls (P=0.0323). In the in vivo experiment, the average corneal thickness was significantly reduced in the treatment group at 15 minutes, 4 hours and 1 day post treatment compared to the controls (P<0.05).
Conclusions :
CXL seems to ameliorate acute swelling of normal and keratoconic human corneas. Also, it can ameliorate the degree of early corneal edema in subsequent acute keratoconus in the murine model.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.