后极部巩膜层间铁异物植入对兔眼生理生化的影响

目的 通过兔眼电生理检查及房水、玻璃体铁离子浓度的检测,评估后极部巩膜层间铁异物植入对兔眼生理生化的影响.方法 选取健康成年日本大耳白兔12只,随机分成两组.以右眼为对照眼,左眼为实验眼.制备2.0mm×1.0 mm×0.2mm中碳铁片,经眶路植入兔左眼后极部巩膜板层内.第一组植入无锈中碳铁片,第二组植入有锈中碳铁片.分别在植入前1周及术后1周、2周、1个月、3个月,对双眼进行闪光视网膜电流图(F-ERG)和闪光视觉诱发电位(F-VEP)检查.在实验结束处死前,抽取兔眼房水和玻璃体并设置空白对照,检测其中的铁离子浓度.运用统计软件SPSS 16.0,采用方差分析,对检测结果 进行统计分析.结果 暗视F-ERG混合反应a波振幅不同时间点之间比较差异无统计学意义(F=1.885,P=0.129),不同处理组之间比较差异也无统计学意义(F＝1.188,p=0.340);b波振幅差异无统计学意义(时间因素F=2.73,P=0.064;处理因素F＝1.114.P=0.367);F-VEP NI波潜时(时间因素F=1.605,P＝0.263;处理因素F=1.556,P=0.314)、PI波潜时(时间因素F=2.329,P＝0092;处理因素F＝2.186,P＝0.103)差异均无统计学意义.房水铁离子浓度各组差异有统计学意义(F＝3.791,P=0.022),其中有锈铁片组与空白对照组比较差异有统计学意义(t=3.32,P=0.004).玻璃体铁离子浓度各组差异有统计学意义(F=3.694,P=0.023),其中有锈铁片组与空白对照组(t＝2.84,P=001)、无锈铁片组与空白对照组(t=3.23,P＝0.005)比较差异有统计学意义.结论 在3个月实验期内,兔眼后极部巩膜层间细小铁异物无论氧化与否,均没有对视网膜视神经造成明确的电生理改变,但房水、玻璃体铁离子浓度较铁异物植入前有明显升高.

Impact of posterior intrascleral iron foreign body on rabbit eyes'physiological and biochemical functions

Objective To evaluate the effect of posterior intrascleral iron foreign body on rabbit eyes＇ physiological and biochemical functions by electrophysiologic examination as well as ferri ion concentration measurement in aqueous humor and vitreous body. Methods Twelve healthy adult Japan flap-eared white rabbits were randomly divided into two groups, the left eye was used as the experimental eye and the fellow eye as control. The medium carbon iron with the size of 2.0 mm × 1.0 mm× 0.2 mm was implanted into the posterior sclera of the rabbit＇ s left eye through the orbit. The first group was implanted with medium carbon iron without rust, and the second group with medium carbon iron with rust. Flash electroretinogram （F-ERG） and flash visual evoked potential （F-VEP） were examined for both eyes 1 week earlier before iron implantation and 1 week, 2 weeks, 1 month and 3 months after the implantation. Furthermore, the aqueous and vitreous ferri ion concentration in each eye was measured before sacrifice at the end of the experiment, and the blank control group was set simultaneously. SPSS 16.0 software package was used for statistic analysis by variance anova. Re- suits There were no statistical difference for the a-wave amplitude of F-ERG scotopic response compared each other at different time points （F = 1. 885 ,P = 0. 129） and different treatment groups （ F = 1. 188, P = 0. 340）. So did the ERG b-wave amplitude （Time Factor F = 2. 73,P = 0.064 ;Treatment Factor F = 1.114,P = 0.367）. There weren＇ t statistical difference for F-VEP Nl-wave latent period （Time Factor F = 1. 605 ,P =0.263 ;Treatment Factor F = 1. 556 ,P =0. 314） and Pl-wave latent period （ Time Factor F = 2. 329, P = 0. 092 ; Treatment Factor F = 2. 186, P = 0. 103 ）. The aqueous ferri ion concentration was statistically significant among groups （F = 3. 791,P = 0.022）, and there was statistical difference between iron with rust group and blank control group （ t = 3.32, P = 0. 004 ）. So did the vitreous ferri ion concentration （ F = 3. 694, P = 0. 023 ）. There was statistical difference between iron with rust group and blank control group （ t = 2. 84,P = 0.01 ） and between iron without rust group and blank control group （ t = 3.23, P = 0. 005）. ConclusionsThere was no definite electrophysiological change of the rabbit eyes caused by the posterior intrascleral iron foreign body with or without rust in the experimental period of three months, but ferri ion concentration of aqueous and vitreous was obviously higher than that before iron foreign body implantation.