兔视网膜光凝术后组织形态学改变的动态观察  

Histomorphological changes of retina following laser photocoagulation in pigmented rabbits

作　　者：覃冬菊[1] 唐罗生[2] 刘湘平[2] 唐朝珍[2] 

机构地区：[1]中国上海市南汇区中心医院眼科,201300 [2]中南大学湘雅二医院眼科,中国湖南省长沙市410011

出　　处：《国际眼科杂志》2008年第5期909-912,共4页International Eye Science

摘　　要：目的:研究532nm激光TsoⅢ级光斑光凝色素家兔视网膜后光凝斑组织形态改变的病理特征。方法:(1)18只色素家兔按光凝后观察时间1,3,7,14,21d及28d分为6组,每组3只。每只(双眼)用532nm激光TsoⅢ级光斑光凝色素家兔视网膜后极部30点(532nm,450mW,100μm,0.05s)。(2)光凝后不同观察时间点行荧光素眼底血管造影(fluorescence fundus angiography,FFA)观察光凝斑FFA特点;取光凝区眼球壁制作标本,进行光镜和透射电镜观察并定量分析视网膜光凝斑大小、视网膜细胞存活率的动态变化。结果:(1)荧光血管造影:光凝后3d,部分光凝斑为高荧光,荧光渗漏随时间延长逐步减轻,至光凝后14d,荧光渗漏基本消失。(2)组织病理学检查:光凝斑区域视网膜各层组织细胞结构破坏;光凝斑周围光感受器细胞的凋亡或坏死和神经节细胞的损伤;继后色素上皮细胞、M櫣ller细胞和成纤维细胞增生修复破坏区。(3)形态学定量指标:光凝后第1d视网膜光凝斑直径最大为116.4±9.6μm,比参照光斑(75μm)增大了55.2%,随后有下降的趋势,21d后为82.8±5.4μm趋于稳定。视网膜细胞存活率光凝后第1d最小为(29.5±4.2)%,随后有上升的趋势,21d为(48.2±4.4)%趋于稳定。结论:视网膜光凝TsoⅢ级光斑会导致光凝斑周围视网膜感觉神经细胞的非选择性、扩展性损伤。AIM ： To study the histomorphological changes of retina following laser photocoagulation by frequency doubled 532nm laser with laser lesion effect of Tso grade Ⅲ photocoagulated spot in pigmented rabbits. METHODS： 1 ） Eighteen pigmented rabbits were photocoagulated at posterior pole by frequency doubled 532nm laser with laser lesion effect of Tso grade Ⅲ photocoagulated spots （532nm, 450mW, 100μm, 0. 05 second） in both eyes, and then were observed at 1, 3, 7, 14, 21, 28 days after photocoagulation. 2 ） The photocoagulated lesions were evaluated by fundus fluorescein angiography （ FFA ）, light microscopy, transmission electron microscopy at every scheduled timepoint. The photocoagulated spots were evaluated histopathologically and morphometrically by quantitatively detecting the diameter of photocoagulated lesion and retinal cell surviving ratio. RESULTS： 1 ） Fluorescein fundus angiography（FFA） ： at 3 days after photocoagulation some photocoagulated spots were of hyperfluorescence, and fluorescein leakage still existed in some photocoagulated lesions, lightened gradually with time, and disappeared in photocoagulated lesions at 14 days after photocoagulation. 2） Histopathological changes： retinal photocoagulation caused apoptosis or necrosis of photoreceptor cells in normal retina adjacent to the laser lesion and damage to ganglion cells. Subsequently the proliferation of RPE, Muiller cells and fibroblasts repaired the destroyed areas of retina. 3） Morphometric changes： at 1 day after photocoagulation,the diameter of photocoagulated lesions increased by 55.2% compared with that of control photocoagulated spots. Then it decreased with time and maintained stable on 21 days. Retinal cell surviving ratio was lowest （29.5 ± 4.2）% at 1day, and increased to （48.2 ±4.4）% at 21 days and maintained stable. CONCLUSION, Laser photocoagulation （Tso grade Ⅲ photocoagulated spot ） can induce non-selective, expanding retinal injury adjacent to laser lesion.

关 键 词：光凝固术 激光损伤 动物实验 兔 视网膜 

分 类 号：R779.63[医药卫生—眼科] R285.5[医药卫生—临床医学]