Peachey N S, Alexander K R, Derlacki D J, Fishman G A
Hines Veterans Affairs Hospital, Ill.
Doc Ophthalmol. 1992;79(4):363-9. doi: 10.1007/BF00160949.
Cone electroretinograms are typically isolated by presenting stimulus flashes against rod-desensitizing adapting fields. To investigate the manner in which adapting-field luminance affects cone electroretinogram response properties, we measured cone electroretinogram luminance-response functions of two normal subjects, with stimuli presented against adapting fields that ranged in luminance from -1.2 to 2.1 log cd/m2. A flicker rate of 31.1 Hz was used to isolate cone electroretinograms under all adaptation conditions. A hyperbolic equation of the form (R/Rmax) = Ln/(Ln + Kn) was fitted to each luminance-response function by a least-squares criterion. As adapting field luminance increased, the best-fit values of the variables K and n increased, which is in general agreement with results of electrophysiologic studies of light adaptation in retinal neurons. However, Rmax values also increased with adapting field luminance. The change in all three of these variables with adapting field luminance must be considered in the interpretation of cone electroretinogram luminance-response functions from patients with retinal disorders.
通常通过在对杆细胞脱敏的适应场中呈现刺激闪光来分离视锥细胞视网膜电图。为了研究适应场亮度对视锥细胞视网膜电图反应特性的影响方式，我们测量了两名正常受试者的视锥细胞视网膜电图亮度反应函数，刺激呈现于亮度范围从 -1.2 到 2.1 log cd/m² 的适应场中。在所有适应条件下，使用 31.1 Hz 的闪烁频率来分离视锥细胞视网膜电图。通过最小二乘法准则，将形式为 (R/Rmax) = Ln/(Ln + Kn) 的双曲线方程拟合到每个亮度反应函数。随着适应场亮度增加，变量 K 和 n 的最佳拟合值增加，这与视网膜神经元光适应的电生理研究结果总体一致。然而，Rmax 值也随适应场亮度增加。在解释视网膜疾病患者的视锥细胞视网膜电图亮度反应函数时，必须考虑这三个变量随适应场亮度的变化。
