明视负波反应在青光眼早期诊断中的临床意义

Clinical significance of photopic negative response in early glaucoma

视网膜电图的明视负波反应(PhNR)是在明适应条件下,用亮光刺激时,在正向b波后记录到缓慢的负向电位,但当用色光作背景和色光作为刺激光时,PhNR反应明显增大。动物实验证实PhNR产生于视网膜神经节细胞及其轴突,在实验性青光眼的视野轻度缺失时出现PhNR振幅下降。PhNR可以在开角型青光眼患者中呈特征性的振幅降低,并在可疑开角型青光眼中表现PhNR振幅降低。提示PhNR可以作为早期开角型青光眼损伤或者其青光眼损伤进展的一个视功能评价指标。

The photopic negative response（PhNR） from photopic electroretinogram is a slowly negative potential following positive b wave. It can be recorded using white or color flash stimulation under the color light background. When using color stimuli and color background,the PhNR amplitude is obviously increased. Animal experiments determine that PhNR arise from retinal ganglion cells and their axons. Experimental glaucoma can suppress PhNR amplitude even visual sensitivity loss of perimetry is still mild. PhNR amplitudes are selective reduced in some suspicious or primary open angle glaucoma patients. PhNR has a potential role of evaluating visual function in the early detection and monitoring for the progression of glaucomatous damage.