摘要
背景眼前后房间是否构成血一眼屏障的一部分一直存有争议，传统的检测方法由于不能测量后房房水的情况而无法提供更好的证据。目的使用对比增强磁共振成像（MRI）研究兔眼虹膜周边切除术后造影剂在前后房的分布，证实眼前后房之间的屏障作用。方法8只清洁级新西兰白兔单眼接受虹膜周边切除术，对侧眼为对照眼。MRI的造影剂钆喷酸葡胺（Gd—DTPA）作为示踪剂，在活体兔耳缘静脉注射0．5mol／L造影剂0．2ml／kg，MRI连续扫描，观察造影剂的渗透性及眼内分布，通过感兴趣区时间相关的信号增强率分析影像。结果兔耳缘静脉注射0．2ml／kgGd—DTPA后，双眼睫状体信号在10min内快速增强，且手术眼的荧光强度强于对照眼。Gd—DTPA注射后30～40min睫状体信号最强，此后逐渐下降，前房信号逐渐增强，手术眼后房信号增强，而对照眼后房呈低信号，Gd—DTPA注射后感兴趣区分别为睫状体、前房和后房，手术眼后房信号增强与前房同步，对照眼后房未发现信号增强。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，眼前后房之间存在着屏障，是血一眼屏障的组成部分。
Background Whether ocular anterior and posterior chamber exist a blood-aqueous barrier is in controversy. Conventional method can not offer a good evidence because it is unable to detect the aqueous component in the posterior chamber. Objective This study was to investigate the distribution of Gadolinium-diethylene triaminc pentaacetic acids （Gd-DTPA） after peripheral iridectomy with magnetic resonance imaging（MRI） in rabbit. Methods Monocular peripheral iridectomy was performed on the right eyes in 8 clean New Zealand white rabbits and the fellow eyes were as controls. 0. 2 ml/kg（0. 5 mol/L）Gd-DTPA, a tracer of MRI, was injected into ear vein in vivo to scan the eyes with MRI for the observation of the permeability and distribution. The signal enhanced ratio of interest region associated with time were analyzed. Results The signal in ciliary body of both eyes showed an immediately sharp enhancement within 10 minutes following the injection of Gd-DTPA with a peak intensity at 30-40 minutes,and then the intensity was gradually weaken over time. The signal was stronger in the operative eyes than that in the fellow eyes. The signal in the posterior chamber was gradually increased after operation, however, that in posterior chamber of the control eyes was lower. The interest regions of Gd-DTPA were ciliary, anterior chamber and posterior chamber,and the enhanced signal intensities were consisted in the posterior chamber after operation. However, the increase of the signal was not seen in the posterior chamber in the control eyes. Conclusions The pathway of plasma protein entering into the anterior chamber is very different from that of aqueous secretion. There exists a barrier between the anterior and posterior chamber which might be an integral part of the blood-ocular barrier.
出处
《中华实验眼科杂志》
CAS
CSCD
北大核心
2012年第7期617-620,共4页
Chinese Journal Of Experimental Ophthalmology
关键词
磁共振成像
钆喷酸葡胺
虹膜周边切除术
血一眼屏障
Magnetic resonance imaging
Gadolinium-diethylene triamine pentaacetic acids
Peripheral iridectomy
Blood-ocular barrier
