老年黄斑变性的局部视网膜电图研究

目的:观察老年黄斑变性(AMD)对视网膜黄斑部电活动影响特征,并对局部视网膜电图(LERG)的敏感性作出评价。方法:对80例AMD患者99只眼进行了黄斑区三个范围局部视网膜电图(LERG)测定,并与患者的视力及相应检测范围病损面积进行了对比研究。结果:黄斑区2.5°、5°、7.5°范围内,干性AMD组LERG平均振幅降低,但与正常对照组间无显著性差异(P>0.05),湿性AMD组LERG平均振幅显著降低(P<0.01)。湿性AMD LERG b波振幅与病人视力呈正相关性,与相应范围病灶面积呈负相关。干性AMD玻璃膜疣数量对LERG尚无影响。结论:不同类型AMD对于黄斑功能损害程度不同,湿性型损害大于干性型;中心凹功能损害大于旁中心凹。LERG在AMD的黄斑功能测定方面是较敏感的电生理方法。眼科学报 1996;12:93—97。

The Study of Local Electroretinogram in Age-related Macular Degeneration

Purpose: Observing the features of electro-activities at macular region in age-related macular degeneration (AMD), and evaluating the sensitivities of local electroretinogram (LERG).Methods:The LERG of 2. 5.5,7. 5 degrees at macula had been recorded in 99 eyes (68 dry form,31 wet form)of 80 AMD patients. The contrast study had also been carried out with visual acuities and lesion areas at the corresponding region. Results :The results showed that there were no significant differences between the decreased amplitudes of a and b waves of LERG in dry form AMD with normal controls (P>0. 05). While significant differences existed in wet form AMD (P< 0. 01). The changes of LERG at 2. 5 degrees were greater than those of the other two regions. The correlation study on b wave amplitude and visual acuity of AMD patients showed that there was a positive correlation existed between them only in wet form AMD at 2. 5 degrees region (r = 0. 516, P < 0. 05). The negative correlations were observed between amplitudes of b wave and lesion areas in wet form AMD at the three macular regions. Drusen of dry form AMD had no effects on the amplitudes of LERG.Conclusions: The impairments on macular function from two types of AMD are different. This study reveals that the LERG is a sensitive method of visual electrophysiology for measuring macular function. The smaller the testing area, the higher the sensitity. Eye Science 1996; 12: 93- 97.