Effect of different biomedical membranes on alkali-burned cornea.

Objective: To evaluate the effects of different biomedical membranes on alkali-burned cornea in vivo.

Methods: 12 New Zealand rabbits were chosen and randomly divided into four groups. The right cornea of each rabbit was made into an alkali-burned model with 1 mmol/l NaOH. Poly-D,L-lactic acid (PDLLA), PDLLA modified with collagen (PDLLA/collagen) and PDLLA modified with chitosan (PDLLA/chitosan) membranes were transplanted onto the alkali-burned corneas for evaluation. Clinical evaluations were performed daily with a slit lamp. On the 12th day after surgery, the progress in wound healing was compared by clinical and histological examination. The reepithelialization of each cornea was evaluated with fluorescein staining and 3 corneas of each group were excised to observe histological changes such as corneal wound healing, inflammation and collagen synthesis.

Results: The wound healing rate of the PDLLA/chitosan group was higher than in the other groups. A more orderly arrangement of collagen and mild inflammation was observed. The control group had the next best performance, while the PDLLA/collagen and PDLLA alone treatment groups showed the worst results.

Conclusion: PDLLA/chitosan promoted wound healing of alkali-burned corneas in vivo and decreased scar tissue formation, while the effect of the PDLLA/collagen and PDLLA membranes was to promote corneal ulcers, which suggests that PDLLA/chitosan membrane transplantation is a potential effective strategy for treatment of alkali-burned cornea.