Pathological Evaluation of Two Techniques of Amniotic Membrane Patching on Experimentally Induced Corneal Lesions in Dogs

Objective- This study was performed to evaluate and compare grossly and pathologically two surgical techniques of amniotic membrane patching on experimental corneal alkali burn in dogs.   Design- Experimental study.   Animals- Fifteen healthy dogs   Procedures- The central corneas of the dogs were inflicted by applying a round filter paper, 6.0 mm in diameter, soaked in 1 N NaOH for 60 sec. A corneal alkali burn was made unilaterally in each dog's eye. A total of fifteen dogs were divided into three groups of five each: (A) uncovered as a control group; (B) covered by amniotic membrane (AM) patching with the amnion cell side down sutured around the corneal wound area with 10/0 nylon as AM+suture group; (C) covered by sutureless amniotic membrane patch adhered by 2-Octyl cyanoacrylate (Dermabond®) as AM+glue group. Time of surgery and AM persistence were recorded. After 3 weeks eyes enucleated and Samples were monitored by evaluating of most important pathological features. Results- The mean time of surgery in group B was significantly longer than group C. AM persistence in group C was significantly more than group B. Corneal thickness measurements and numbers of epithelial rows showed no significant statistical differences between different groups. Group C has had significant lower degree of corneal vascularization than group A. Stromal edema was most prominent in group A, but statistical analysis revealed no significant statistical differences between groups. Stromal collagen arrangement showed no significant differences. AM patched corneas (group B, C) show lower inflammation, compared with the uncovered one (group A). Among the AM patching groups, the group C revealed the best result. Conclusion and Clinical Relevance- use of the sutureless amniotic membrane patching with 2-Octyl cyanoacrylate as a dressing on a corneal alkali burn could induce rapid epithelial healing with less inflammatory response as well as reduce the time of operation in dogs.