Ishikawa M, Miyake Y, Shiroyama N
Department of Ophthalmology, Nagoya University School of Medicine, Japan.
Nippon Ganka Gakkai Zasshi. 1990 Nov;94(11):1040-7.
To investigate early changes of the macula in eyes with myopia, we compared 66 eyes with high myopia with 76 normal eyes by recording focal macular electroretinogram (ERG). The eyes with high myopia were divided into two groups; eyes showing only tigroid fundus (group 1) and those associated with posterior staphyloma involving the macula (group 2). The visual acuity of groups 1 and 2 was 1, 0 or better and 0.8 or better, respectively. The amplitude of the a-wave, b-wave in group 1 was significantly smaller than that of normal eyes, however the peak latency was within the normal range. The amplitude of a-wave, b-wave and oscillatory potentials in group 2 was significantly smaller and the peak latency was significantly longer than those in group 1. The abnormal amplitude with normal peak latency in group 1 suggests some reduction of numbers of cones, which is considered to be an early pathologic change in the macula with high myopia. The more reduced amplitude with delayed peak latency in group 2 suggests that, in the advanced stage, the macular pathologic finding includes some quantitative damage as well as further reduction of macular cones.
为研究近视眼中黄斑的早期变化，我们通过记录黄斑局部视网膜电图（ERG），对66只高度近视眼和76只正常眼进行了比较。高度近视眼被分为两组：仅表现为豹纹状眼底的眼（第1组）和伴有累及黄斑的后巩膜葡萄肿的眼（第2组）。第1组和第2组的视力分别为1.0或更好以及0.8或更好。第1组的a波、b波振幅明显小于正常眼，但峰潜伏期在正常范围内。第2组的a波、b波和振荡电位的振幅明显更小，且峰潜伏期明显长于第1组。第1组中峰潜伏期正常但振幅异常提示视锥细胞数量有所减少，这被认为是高度近视眼黄斑的早期病理变化。第2组中振幅进一步降低且峰潜伏期延迟提示，在疾病晚期，黄斑的病理表现包括一些定量损伤以及黄斑视锥细胞的进一步减少。
