Abstract
Purpose:
To analyse the impact of corneal crosslinking, using riboflavin and UVA-light illumination on existing blood and lymphatic vessels in the cornea.
Methods:
We used the established murine model of suture-induced inflammatory corneal neovascularisation assay. 14 days after suture placement we removed the sutures.<br /> The mice underwent corneal abrasion and received cross-linking treatment using 0.1% riboflavin-5-phosphat solution (Mediocross H) (1x riboflavin-5-phosphat drop in 15 minutes) and subsequent UVA-light-illumination (370 nm; irradiance, 3 mW/cm2; dose, 5.4 J/cm2, 1x riboflavin-5-phosphat drop) for 15 minutes.<br /> After four days, corneal blood and lymphatic vessels were stained ex vivo using LYVE-1 and CD31 antibodies. Depth of cross linking was assessed by measuring the nucleus free area between Bowmann's layer and corneal endothelium using Dapi staining and an ApoTome2 microscope.
Results:
The cross linked corneas showed an enhanced rigidity as a sign of successful cross linking and were not perforated. The corneal stroma was cross linked to a mean depth of 23.96% (SD 18.5%) of total corneal stromal thickness. Furthermore we found a significant negative correlation between the depth of cross linking and the area covered by blood vessels (p=0.018; r2= 0.881). Epithelial healing was delayed in the crosslinked animals.
Conclusions:
We demonstrate a novel murine model of corneal crosslinkink. Crosslinking in murine corneas is a new way to analyse the effect of this clinically often used method on corneal cells. This pilot study shows that crosslinking can regress pathological corneal blood vessel in a depth dependent manner. Therefore this is a promising model to develop a new strategy to regress preexisting corneal vessels prior to keratoplasty.