应用ERG技术评估玻璃体注射CsA对视网膜功能的影响

Retinal functional evaluation following intravitreal injection of CsA microsphere using ERG technique

目的 应用视网膜电图（ERG）测试技术评估环孢霉素A（CsA）微球玻璃体注射后对视网膜功能的影响。方法 用含有 750μg的 CsA可降解微球5mg分别注入10只有色兔的右眼作为实验眼,每只兔的左眼注入同等剂量的空白微球作为对照眼。于注射前及注射后的第1、2、4、6周分别对每只兔的左右眼进行暗适应闪光ERG记录。实验后摘除眼球光镜下组织学观察视网膜结构改变。结果 暗适应ERG最大反应b波平均振幅在玻璃体注射后的第1～2周明显下降（P<0.05,<0.05）,下降的最大峰值在第1周,4～6周恢复至实验前水平。实验眼与对照眼的b波比率均值在注射后第1～2周明显下降（P<0.05,<0.05）,第4～6周恢复正常。a波振幅及a、b波潜伏值实验前后比较或与对照眼比较无明显差异。光镜下视网膜各层结构在玻璃体注射后无明显变化。结论 含750ug CsA的5mg可降解微球经玻璃体注射后对视网膜内层功能可产生可逆的影响,ERG可作为检测CsA对视网膜功能影响的可靠指标。

Objective To evaluate the retinal toxicity of CsA microsphere after it was injected into vitreal with ERG technique. Methods Ten pigmented rabbits were used in this study. A dose of 5 mg microsphere contained 750 μg CsA was injected intravitreally into the left eye of each rabbit and a same dose of microsphere without CsA into right eye ( conlral eyes). ERG responses were recorded at the 1 st,2 nd,4 th and 6 th week postinjectivelly and the histologic examination for experimental and control eyes were performed to assess retinal functional and structural changes. Results Mean b-wave amplitude ot scotopic ERG were remarkably reduced at the first 2 weeks ( P < 0. 05 , < 0. 05 ). A maxmume depression in b-wave ratio (left: right) was presented at the first week. The b-wave amplitude returned gradually to normal during 4 ~ 6weeks following injection. No significant difference were seen in a-wave amplitude and a b-waves latencies in both experimental and control eyes between before and after experiment. No historic change was fount in both two groups up to 6 weeks. Conclusions The effect of a 5 mg microsphere contained 750 μg CsA on retinal inner layer function is reversible, ERG can monitor retinal functional change after CsA microsphere intravitreal injection.