Safety evaluation of rabbit eyes on scleral collagen cross-linking by riboflavin and ultraviolet A

BackgroundTo evaluate the safety of the scleral collagen cross-linking (CXL) transferred from corneal CXL in rabbit eyes using histology and electroretinography (ERG). MethodsStress-strain measurement was performed five rabbits 1 week after scleral CXL. Dark-adapted ERG was repeatedly applied on bilateral eyes of 10 rabbits before, and 1 week, 1 month and 3 months after the CXL operation. Histological analysis, terminal deoxynucleotidyl transferase dUTP nick-end labeling, the measurement of outer nuclear layer thickness and transmission electron microscopy were performed onto 15 rabbits at corresponding time points postoperatively. ResultsThe mechanical and biochemical stability of rabbit scleral tissues was statistically increased after the scleral CXL (P=.00). However, the dark-adapted ERG amplitudes were statistically reduced 1 week, 1 month and 3 months postoperatively (P<0.05). Compared with the control eyes, apoptotic cells and ultrastructural changes can be found in the retinal layers of scleral cross-linked eyes. ConclusionsAccording to the electrophysiological and histopathological results, the current scleral CXL laboratory technique is not safe enough for the postoperative visual function of rabbit eyes.