Experimental Research Of Porcine Small Intestinal Submucosa (SIS) To Become Material Of Lamellar Keratoplasty

Thirty-six healthy white rabbits without any ocular disease and weighing 2.0 to 2.5 kg were used in this experiment.Twenty-one of them were divided equally at random into three experimental group,namely A, B and C, numbering every white rabbit in respective experimental group.The corneal thickness of five white rabbits of remnant were measured and seven white rabbits of remnant were control group(the white rabbits without any ocular disease and taking lamellar keratoplasty under same breeding condition and same time) ,in addition three white rabbits were pre-emergency.According to the corneal thickness measured, a 7.0mm Hessburg-Barron corneal trephine was used to incise cornea into different deep defect in respective experimental group and placed 7.75mm SIS implant over the corneal defect.The implant was continuous sutured over the defect.The reaction of white rabbit corneal was observed and recorded everyday within postoperative observation period constituted 105 days.These reaction include conjunctival hyperemia and oedema,iritis,corneal neovascularization and oedema of the peripheral cornea and contraction generated during the corneal stroma remodeling. To make a dynamic state observation,one white rabbit of every experimental group was sacrified respectively at 15 days and 45 days postoperative.The remnant of every experimental group was sacrified at 105 days postoperative.After enucleation.the corneas were dissected from the globes and mounted in paraffin. Paraffin sections were stained with haematoxylin and eosin to be examinated by light microscopy. I will find whether there was difference in prognosis when place SIS implant over different deep corneal defect. The results were as follows:1. The small intestine submucosa(SIS) home-maded was placed over the defect of different depth.After 105 days experimental observation,the restore of corneal transparency was satisfied on the whole.2.The restore of recipient corneal transparency had nothing to do with the depth of corneal defect, conjunctival hyperemia and oedema,iritis,corneal neovascularization and the contraction during the course of remolding.3.Being corneal surrogate,SIS implant can be applied to lamellar keratoplasty of different corneal defect.Though the operation had somewhat difficulty,the results were ideal and it had considerable value of clinic generalization.