Experimental Study Of Fresh Amniotic Membrane Transplantation For Corneal Alkali Burns In The Early Stage

Purpose. To investigate the effect of fresh amniotic transplantation onthe treatment of early Gorneal alkali bums (CAB). We understood thecurative mechanism of fresh amniotic membrane transplantation onthe effect of polymorphonuclear leukocyte (PMN) in the comeas,corneal neovascularization, corneal epithelial healing and relation offree radical. We observed the epithelial morphological aPpearanceand connection between Gomeal epithelial cells by using the scanningelectron microscopy (SEM) and transmission electron microscopy(TEM).Metbod8. 48 New Zealand rabbits (48 eyes) were used to makecorneal alkali bum models. 24hrs after burns, the rabbits weredivided into fresh amniotic membrane transplantation groups (f AMT),preserved amniotic membrane transplantation groups (pAMT), andcontrol groups (C). l4 and 30 days after operation, we measured theGontents of polymorphonuclear leukocyte in cornea by usingcomputer image analysis, measured the vitality of superoxidedismutase (SOD) and the contents of malondialdehyde (MDA) incornea and aqueous, analysed Gorneal neovascularization and cornealepithelial healing, and did a ultrastructure morphologiGal observation.ResuIts. By measuring the contents of PMN in cornea, we found2that PMNs in fAMT were lower than that in pAMT. PMNs in fAMTand in pAMT were lower than that in C. By observing of clinicalaPpearance, we discovered that fAMT had stronger effect on reducing- neovascularization and prompting epithelial healings, which was. identical with infiltration of PMN. Through measuring of free radicalindex, we found the vitality of SOD in cornea and aqueous was higherthan that in pAMT both were higher than in C, and the result of MDAwas reverse. By using scanning electron microscopy (SEM) andtransmission elcctron microscopy (TEM), we observed that cornealepithelia in fAMT grew well, having abundant microvillus on itssurface, arranging more regular, and the number of desmosomebetween cells in fAMT was most of three, those in pAMT were thesecond. Epithelia in C grew slowly, and their shape was irregular,edema in evidence, loosen between cells connection, and manyinflammatory cells infiltrated in corneal stroma.Conclu8ion8. The result of our study revealed that AMT couldeffectively reduce inflammatory infiltration, neovascularization, freeradical's production, and improve epithelial healings. On the above- side, we fOund that fAMT has more effective than pAMT which both, are more effective than C.