原发性视神经萎缩的视网膜电图明视负向反应研究

Photopic Negative Response of Flash Electroretinogram in Primary Ocular Nerve Atrophy

目的:研究原发性视神经萎缩的视网膜电图(ERG)明视负向反应(PhNR)变化特点,并进行PhNR与视网膜神经纤维层厚度(RNFLT)、视野平均缺损值(MD)、杯盘比(C/D)的相关性研究,探索PhNR在原发性视神经萎缩的诊断及视神经节细胞功能评价中的作用。方法:选取正常健康者20例20只眼和原发性视神经萎缩的患者18例20只眼。分别对两组进行ERG、视野、眼底照相和OCT检查,比较两组视网膜电图PhNR振幅,并将原发性视神经萎缩组的PhNR振幅分别与MD、C/D和RNFLT进行相关性分析。结果:原发性视神经萎缩组和对照组的ERG中暗视反应、最大反应、30Hz震荡电位的振幅差异无显著性意义,视神经萎缩组明视反应a波和b波振幅差异也没有显著性意义,但原发性视神经萎缩组的PhNR振幅比对照组明显下降(P<0.01),而且PhNR的振幅与视神经损伤情况如RNFLT(r=0.665)、MD(r=0.564)、杯盘比(r=0.686)等相关(均为P<0.01)。结论:原发性视神经萎缩眼视网膜电图PhNR振幅明显下降甚至消失,PhNR可用于原发性视神经萎缩的诊断和神经节细胞及其轴突功能的评价。

Objective： To study the waveform of the photopic negative response（PhNR）in electroretinogram（ERG）, and the relationship between PhNR and retina nerve libra layer thickness（RNFLT）, visual field mean defect（MD）, or cup/disc ratio（C/D）, and to evaluate PhNR in diagnosis of primary ocular nerve atrophy and evaluation of ocular nerve ganglion cells. Methods： Twenty normal cases （20 eyes） and eighteen primary ocular nerve atrophy cases （18 eyes） were involved in this study. Both groups accepted ERG, visual field, Fundus photographs and optic coherence tomography （OCT） examination. Results： The amplitudes of the rod, maximum, and 30 Hz flicker ERG between two groups were not different（P〉0.05）. The amplitudes of a and b wave in cone ERG between them were not different, but the amplitudes of the PhNR were significantly reduced in group of primary ocular nerve atrophy （P〈0.01）. PhNR amplitude was significantly correlated with RNFLT（r=0. 665, P〈0.01）, MD（r=0. 564, P〈0.01） and C/D （r=0. 686, P 〈0.01）. Conclusion： The amplitudes of the PhNR were significantly reduced or disappeared in primary ocular nerve atrophy eyes, so it can be used to diagnose primary ocular nerve atrophy and evaluate the function of ganglion cells or their axons.