纤溶酶和透明质酸酶诱导猪玻璃体后脱离的实验研究

Experimental study on plasmin and hyaluronidase inducing posterior vitrous detachment of pigs

目的研究纤溶酶和透明质酸酶诱导猪玻璃体后脱离(PVD)的有效性和安全性,比较两种酶单独应用和联合应用的效果。方法15只小型猪随机分为A、B、C三组,每组5只,随机选取一只眼为实验眼,对侧眼为对照眼,A组实验眼玻璃体腔注射50U/0.1ml透明质酸酶,B组实验眼注射0.5U/0.1ml纤溶酶,C组实验眼注射0.5U/0.05ml纤溶酶和50U/0.05ml透明质酸酶,对照眼均注射平衡盐溶液(BSS)0.1ml。注药后进行裂隙灯、直、间接检眼镜、眼B超、视网膜电图(ERG)等检查,7d后摘除眼球进行光镜、透射电镜、扫描电镜检查。结果B超检查显示A组有一只实验眼、B组有两只实验眼于注药后1d观察到部分性PVD,C组有一只实验眼于注药后1h观察到部分性PVD。B超、光镜和扫描电镜检查显示注药后7dA组和B组实验眼均见部分性PVD,C组实验眼均见完全性PVD,对照眼未见PVD。实验及对照眼注药前、后ERGa波、b波波幅均无显著性差异,光镜及透射电镜检查未见视网膜损害。结论0.5U纤溶酶和50U透明质酸酶单独及联合应用均可快速、安全、有效地诱导猪眼玻璃体后脱离,且联合用药较单独用药诱导PVD更快速、更有效。

Objective To investigate the efficacy and safety of intravitreal injection of plasmin or hyaluronidase or the combination of these two proteases on inducing posterior vitreous detachment （PVD ） and evaluate the efficacy of these three methods. Methods 15 little type pigs were assigned to three groups （ group A, B and C ） ,5 in every group. Any eye of every pig was injected proteases ,the follow eye was control. Group A received a vitreous injection of hyaluronidase 50 U/ 0. 1ml. Group B received plasmin 0.5 U/0. 1ml. Group C received plasmin 0.5 U/0.05ml combined with hyaluronidase 50 U/0.05ml. The fellow eyes were injected 0. lml balanced salt solution（BSS）. All the pigs were examined with slit -lamp biomicroscopy ,direct and indirect ophthalmoscope, B-scan and electroretinography （ERG ）. After 7 days, the animals were killed and the eyes were enucleated and examined with light microscopy,transmission electron microscopy and scanning e- lectron microscopy. Results B-scan examination showed that one eye of group A and two eyes of group B had partial PVD at 1 day after injection and one eye of group C at 1 hour. B-scan,light microscopy and Scanning electron.microscopy examination demonstrated that at 7days after operation , all the eyes of group A and group B were induced partial PVD, all the control eyes no PVD. The b-wave and a-wave amplitudes of ERG showed no significant difference compared with preinjection values in all groups and between the experimental eyes and controls. Light microscopy and transmission electron microscopy inducated no damage to the retinal structure. Conclusion Intravitreal injection of hyaluronidase 50U or plasmin 0. 5U or their combination can produce PVD effectively and fast without toxicity to the histology and function of the retina. The combination of the two proteases was prior to either of them alone.