高度近视眼黄斑部视网膜厚度及多焦视网膜电图的测定分析

目的检测高度近视眼屈光度数、眼轴长度、黄斑中心凹视网膜神经上皮层厚度及多焦视网膜电图（multifocal electroretinography,mfERG）各波的反应密度与潜伏期,并与正常人比较,评价其差异。方法选择高度近视患者30例（30眼）和正常对照组30例（30眼）,用A超测量眼轴长度,光学相干断层扫描仪（optical coherence tomography,OCT）测量黄斑中心凹神经上皮层厚度,mfERG检测黄斑部视网膜电图各波反应密度及潜伏期,分析高度近视眼屈光度数、眼轴长度、中心凹部神经上皮层厚度及mfERG各波的反应密度、潜伏期。结果高度近视眼平均眼轴长为（28.10±2.67）mm,与对照组比较,差异有统计学意义;黄斑中心凹平均神经上皮层厚度为（163.67±4.93）μm,与对照组比较,差异无统计学意义;黄斑部mfERG反应密度N1波为（18.26±4.95）nV/deg2,P1波为（30.97±10.58）nV/deg2,N2波为（23.66±9.03）nV/deg2,同正常值相比,各波反应密度显著下降,潜伏期差异无统计学意义。结论高度近视眼与正常眼相比,眼轴增长,但黄斑区神经上皮层厚度尚未有明显改变。黄斑部mERG各波反应密度皆降低,提示视网膜感光细胞功能下降。

Measurement and analysis of retinal thickness and multifocal electroretinography of the macula in high myopia subjects

Objective To measure refractive power, axial length, thickness of the neuroepithelial layer of the fovea and analyze multifocal electroretinograms （mfERG） in high myopia patients and compare these measurements with those of normal people. Methods Thirty high myopic eyes were selected. Axial length was measured by A scan ultrasonograpy, and optical coherence tomography （OCT） was used to measure the thickness of the neuroepithelial layer. The mfERG responses from 103 retinal locations were recorded and analyzed. Results The average axial length in high myopia was （28.10 ±2.67）mm and the average thickness of the neuroepithelial layer was （163.67±4.93）μm, having no significant difference com- pared to normal eyes. The response density of the N1 wave of the macula declined to （18.26±4.95）nV/deg2, the P1 wave to （30.97± 10.58）nV/deg2 and the N2 wave to （23.66±9.03）nV/deg2. The latent period of these waves showed no significant difference for myopic eyes compared to normal eyes. Conclusion Compared to normal eyes, axial length is longer in high myopia while the thickness of the neuroepithelial layer do not change and the response density decrease which imply that the function of photoreceptor cells has declined.