增强MRI评价抗青光眼药物对血-房水屏障的影响  

Feasibility of contrast-enhanced MRI for evaluating the effects of anti-glaucoma drugs on blood-ocular barrier

作　　者：陈辉[1] 毛晓春[2] 査云飞[1] 曹丰[3] 樊建中[3] 

机构地区：[1]武汉大学人民医院放射科,武汉430060 [2]襄阳市中心医院眼科,湖北441000 [3]襄阳市中心医院放射科,湖北441000

出　　处：《放射学实践》2016年第4期355-358,共4页Radiologic Practice

摘　　要：目的：探讨增强MRI评估抗青光眼药物滴眼后对血-房水屏障影响的可行性。方法：将12只健康洁净新西兰白兔分为两组,A组采用单眼滴注1%盐酸匹鲁卡品滴眼液,B组采用单眼滴注0.25%噻吗心安滴眼液,以对侧眼作为对照。静脉注射Gd-DTPA 0.2mL后行MR动态增强扫描,共扫描10次（1h内每间隔10min行1次MRI,1h以后间隔15min行1次MRI）。测量各时间点前房、睫状体和后房的平均信号强度,绘制时间-信号增强率曲线,观察对比剂在眼内的分布情况。结果：在注射对比剂后2组中实验眼睫状体信号迅速增高,15min后达到最高峰,信号增强率为109.0%±5.8%,此后信号强度逐渐下降;前房信号呈缓慢增高,50~60min到达峰值,信号增强率为98.0%±6.3%,高于对照眼（59.0%±4.6%）,差异有统计学意义（P〈0.05）;双眼后房均未见信号增强,始终为低信号。结论：血浆蛋白进入前房途径与房水分泌途径是分别独立的通道,眼的前后房之间存在着屏障,使用抗青光眼药物后并没有破坏血-房水屏障;增强MRI可用于评估眼的房水循环情况。Objective：To investigate the Feasibility of contrast-enhanced MRI for evaluating the effects of anti-glaucoma drugs on blood-ocular barrier.Methods：Twelve purebred New Zealand white rabbits were divided into group A and group B.Rabbits from group A were given eye drips of 1% pilocarpine while rabiits from group B were treated with eye drips of 0.25%timolol in right eyes.The left eyes of all rabbits were left untreated for control.Gadolinium-diethylenetriaminepentaacetic acids（Gd-DTPA）enhanced MRI were performed to both eyes of these rabbits,once per 10 min within the first hour and once per 15 min post one hour after injection of Gd-DTPA with a dose of 0.2mL/kg（0.5mol/L）through the ear vein.The signal enhanced ratios（SER）of anterior chamber,ciliary body and the posterior chamber were measured as signal intensity of right eyes divided by signal intensity of corresponding areas of left eyes.The SER-to-time curves were drawn,in order to assess the permeabilityand distribution of the contrast agent.Results：The SER-to-time curves showed that SER in ciliary body increased dramatically and reached peaks at 15 min after injection,The signal enhanced ratios（SER）was 1.09±0.058,followed by a slow decline.The SER in anterior chamber rose up a bit slowly to peaks at about 50~60min after injection,The SER was 0.98±0.063 in the anterior chamber of the right eyes,The SER was 0.59±0.046 in the anterior chamber of the left eyes,Signal enhancement of the anterior chamber were obvious in the right eyes of all rabbits,but none signal enhancement were observed in posterior chamber.Conclusion：The path way of plasma protein entering into the anterior chamber is different from that of aqueous secretion.A barrier between the anterior and posterior chamber may exist and may be a component of blood-ocular barrier.Anti-glaucoma drugs will not damagethis barrier.

关 键 词：磁共振成像 钆喷酸葡胺 青光眼 血-房水屏障 

分 类 号：R445.2[医药卫生—影像医学与核医学] R775.3[医药卫生—诊断学]