微型角膜刀联合纤维蛋白黏合剂行无缝线光学板层角膜移植术的实验研究

Sutureless lamellar keratoplasty by microkeratome combined with fibrin tissue adhesive in rabbits

目的 探讨微型角膜刀联合纤维蛋白黏合剂行无缝线光学板层角膜移植术的可行性和安全性。方法 2 4只健康纯种新西兰白兔随机均分为两组 ,用微型角膜刀制作植片和植床 ,Ⅰ组应用市售纤维蛋白生物黏合剂Tisseel,Ⅱ组不用纤维蛋白生物黏合剂。术后 3d、2周、1个月、3个月裂隙灯显微镜观察角膜透明度和排斥反应情况 ,自动验光角膜曲率仪检测角膜屈光状态的改变 ,共焦显微镜活体观察术后角膜的创伤愈合反应。同期取角膜标本进行常规苏木素 伊红 (HE)观察 ,并用荧光显微镜观察层间新生胶原纤维的情况。结果 Tisseel组 11只眼 (92 % )的植片在位 ,未用纤维蛋白生物黏合剂组所有植片均脱落。Tisseel组术后 1个月角膜完全透明 ;共焦显微镜发现术后植片植床层间附近的基质细胞数量减少 ,而后基质细胞、内皮细胞数量和形态均无变化。HE染色显示 ,术后 3d层间出现无固定形态的嗜曙红染色带 ,1个月时消失 ,荧光显微镜观察DTAF组织染色未见术后明显新生胶原纤维。结论 微型角膜刀联合纤维蛋白黏合剂行无缝线光学板层角膜移植术简便、安全 ,术后角膜的创伤愈合反应轻微 ,纤维蛋白黏合剂不影响角膜的光学性能。

Objective To evaluate the feasibility and safety of sutureless lamellar keratoplasty by microkeratome combined with fibrin tissue adhesive. Methods Twenty-four New Zealand white rabbits were divided into two groups,the donor grafts and recipient beds were made by the microkeratome,the grafts were glued over the stoma bed using the commercial product Tisseel in one group; and grafts without tissue adhesive were used as the control group. Corneal refractive power was measured by automated keratometer preoperatively and in 3 days,2 weeks,1 and 3 months postoperatively. Rejection and cornea transparency were observed. Confocal microscopy was used to observe corneal wound healing response and to measure the keratocyte and endothelium densities in vivo. Corneal wound healing was also evaluated using light and fluorescence microscopy. Results Ninety-two percent (11/12 eyes) of the glued grafts were retained in the Tisseel group,whereas all grafts were lost in the control group. All survived grafts were clear 1 month after surgery. However,in the control group,severe haze in the grafts occurred 2 weeks postoperatively. Confocal microscopy showed that there was a significant decrease of the keratocyte density surrounding the lenticule-host interface,and no changes occurred in the posterior keratocyte and endothelium. Histopathologic observations demonstrated the presence of a line of amorphous eosinophilic substance in the lenticule-host interface at 3 days after surgery,but the line disappeared after 1 month. Fluorescence microscopy showed no detectable regenerated stromal tissue. Conclusions This initial study demonstrates sutureless optical lamellar keratoplasty performed by microkeratome combined with fibrin tissue adhesive is a simple and safe technique. Stromal wound healing response to this surgery is minimal. Fibrin tissue adhesive has no influence on the cornea optical property.