Cryopreserved Amniotic Membrane Transplantation to Cicatrisation of Cornea with Limbal Stem-Cell Deficiency.
D.N. Cremonini; J.J.T Ranzani; M.E.A. Marques; G.N. Rodrigues; C.V.S. Brandão; T.P. Peixoto
Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista, UNESP, Campus Botucatu-Brasil
Introduction: The following research was conducted with the intent of evaluating changes related to limbal stem-cell deficiency in corneal epithelium in rabbits, as well as analyzing the results that amniotic membrane transplant had over this cicatrisation.
Materials and Methods: The corneal ulcer was induced by putting n-heptanal associated to 360° conjunctival peritomy in rabbits; the following step was to cover the surface with canine amniotic membrane, secured to perilimbal episclera, cryopreserved in embryo holding solution (Group II) or amniotic membrane medium (Group III), both with 50% glycerol and stored at -80°C, except the control group (Group I), which was not treated with membrane. Each group was composed with five animals, which were examined daily at clinical exam and morphologically at seven, 15 and 30 days, by hematoxylin-eosin and periodic acid-Schiff stains. The results obtained where evaluated by nonparametric tests seeking a comparison of effect of the moments in each group, by the test of Friedman and the effect in the groups in each moment by the test of Kruskal-Wallis. The significance level adopted, for each of the variables, was 5% of probability.
Results: All of them, including the treated groups, developed signs of limbal stem-cell deficiency, entitled conjunctivalization, due to the occurrence of neovascularization, chronic inflammation and recurrent epithelial defects; during corneal histopathology it was observed the occurrence of neovascularization, edema, leukocytes and goblet cells. The amniotic membrane was present up to the eleventh day in Group II and ninth day in Group III. There was no statistical difference between the groups, however, biologically the Group II had less corneal inflammation than Groups I and III.
Conclusion: The amniotic membrane transplant was not efficient in the treatment of limbal stem-cell deficiency, however it did help in the process of cicatrisation, demonstrating to be more efficient when preserved in embryo solution.