Chen Jennifer C, Brown Brian, Schmid Katrina L
School of Optometry and Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia.
Vision Res. 2006 Oct;46(20):3413-21. doi: 10.1016/j.visres.2006.03.013. Epub 2006 May 2.
There is evidence that the inner retina is involved in eye growth control processes and the development of myopia. We sought to investigate the response dynamics of the inner retina of adult emmetropes and myopes using the global flash multifocal electroretinogram (mfERG) paradigm.
Fourteen myopes and 10 emmetropic subjects (mean age: 21.0+/-2.8 years) underwent mfERG testing using VERIS 5.1.5X. The global flash stimulus array consisted of 103-scaled hexagons which flickered according to a pseudorandom binary m-sequence (2(13)-1). The stimulation sequence was modified by inserting three frames, a dark frame, a global (full screen) flash, and another dark frame. The amplitude and implicit time of the two distinct waveform features, an early direct component (DC) and a later induced component (IC) of the first-order kernel were analyzed. Retinal responses were averaged over rings of increasing eccentricity, or into nasal and temporal hemifields.
There was a significant correlation between the DC and IC response amplitude and myopic refractive error, i.e., the greater the myopic error, the greater the response amplitude. However, when comparing between the two refractive error groups, DC and IC response amplitudes of emmetropes and myopes were similar, even after compensating for the effect of axial length. There were no significant differences in implicit times of the DC and IC in emmetropes and myopes.
Global flash mfERG responses of emmetropes and myopes were not found to be significantly different. The measured retinal adaptation response however varied according to the degree of myopia. We hypothesize that dopamine, a neurotransmitter that plays a key role in retinal adaptation and is known to be reduced in myopic eyes, may be involved in the retinal adaptation effect observed.
有证据表明，视网膜内层参与眼球生长控制过程以及近视的发展。我们试图使用全视野闪光多焦视网膜电图（mfERG）范式来研究正视和近视成人视网膜内层的反应动力学。
14名近视者和10名正视者（平均年龄：21.0±2.8岁）使用VERIS 5.1.5X进行mfERG测试。全视野闪光刺激阵列由103个缩放的六边形组成，这些六边形根据伪随机二进制m序列（2¹³ - 1）闪烁。刺激序列通过插入三个帧进行修改，一个暗帧、一个全视野（全屏）闪光和另一个暗帧。分析了一阶核的两个不同波形特征，即早期直接成分（DC）和后期诱发成分（IC）的振幅和隐含时间。视网膜反应在偏心度增加的环上或鼻侧和颞侧半视野中进行平均。
DC和IC反应振幅与近视屈光不正之间存在显著相关性，即近视度数越大，反应振幅越大。然而，在比较两个屈光不正组时，即使在补偿眼轴长度的影响后，正视者和近视者的DC和IC反应振幅仍相似。正视者和近视者的DC和IC隐含时间没有显著差异。
未发现正视者和近视者的全视野闪光mfERG反应有显著差异。然而，所测量的视网膜适应反应根据近视程度而变化。我们假设多巴胺，一种在视网膜适应中起关键作用且已知在近视眼中减少的神经递质，可能参与了所观察到的视网膜适应效应。
