Department of Ophthalmology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Centre, UPMC Eye Centre, Pittsburgh, PA, 15201, USA.
School of Medicine, University of Pittsburgh, Pittsburgh, PA, 15201, USA.
Doc Ophthalmol. 2021 Apr;142(2):185-193. doi: 10.1007/s10633-020-09793-w. Epub 2020 Sep 21.
This study evaluated a new light-emitting diode (LED-S) photic stimulator and compared skin electroretinogram (ERG) responses obtained to those evoked by the Grass Instrument stimulator (GP-S).
Two sub-studies were combined to evaluate the difference in responses resulting from the LED-S and GP-S stimuli. The first was a photometry study that matched the LED-S stimuli to the GP-S. In the second study, electroretinograms (ERGs) were recorded under scotopic and photopic conditions using stimuli each stimulator. The stimuli were matched photometrically to measurements obtained from the photometer located 30 cm in front of the stimulators. In addition, the ERG responses were recorded from the LED stimulator when photometrically matched to the GP-S blue stimulus presented through a ganzfeld. The amplitudes and time peaks of the resulting ERG a- and b-waves were then measured and compared using paired T-tests.
Study 1: The LED-S was matched to the GP-S at various intensity settings measured 30 cm away from the stimulator. Measurement through a ganzfeld full-field stimulator (GFFS) demonstrated that the GP-S had a significant hot spot centrally. Study 2: Photometrically matched ERGs evoked by both stimulators while employing the direct head-on measurements demonstrated multiple similarities. Similarities included component morphology, amplitude and implicit time across the two stimulators, excluding the rod-driven stimulus (GP-S setting employing a blue filter). Differences between the rod-driven ERGs evoked by the GP-S and LED-S while employing head-on photometric measurements were due to the significant difference in intensities between the two stimulators. The GP-S and LED-S evoked similar rod-driven ERG responses when they were matched using the GFFS photometrically matched intensities protocol.
A hand-held stimulator is essential when recording ERG's in the practice of paediatric visual electrophysiology. The LED-S can match the GP-S stimulus intensities, making it a potential replacement for the GP-S. In addition, the LED-S has uniform intensity across the surface of the device compared to the GP-S, is silent for standard stimuli and can generate prolonged duration stimuli for the recording of on-off ERGs.
本研究评估了一种新型发光二极管（LED-S）光刺激器，并比较了其与 Grass 仪器刺激器（GP-S）诱发的皮肤视网膜电图（ERG）反应。
将两项子研究结合起来，评估 LED-S 和 GP-S 刺激产生的反应差异。第一项是光度学研究，将 LED-S 刺激与 GP-S 匹配。在第二项研究中，在暗适应和明适应条件下使用每个刺激器记录视网膜电图（ERG）。通过将刺激器前 30 厘米处光度计测量的光度匹配来刺激。此外，当通过全视野刺激器（GFFS）将 LED 刺激器的光度匹配到 GP-S 蓝色刺激时，记录 ERG 反应。然后使用配对 T 检验测量并比较产生的 ERG a 和 b 波的振幅和时间峰值。
研究 1：将 LED-S 与 GP-S 在远离刺激器的各种强度设置下进行匹配。通过全视野刺激器进行测量表明，GP-S 中央有一个明显的热点。研究 2：直接面对面测量时，两种刺激器的光度匹配 ERG 表现出多种相似性。相似之处包括两种刺激器之间的组件形态、振幅和潜伏期，排除了棒状驱动刺激（GP-S 设置采用蓝色滤光片）。当使用直接面对面光度测量时，GP-S 和 LED-S 诱发的棒状驱动 ERG 之间的差异是由于两种刺激器之间的强度差异显著。当使用 GFFS 光度匹配强度方案匹配时，GP-S 和 LED-S 诱发的棒状驱动 ERG 反应相似。
在小儿视觉电生理实践中，手持式刺激器对于记录 ERG 至关重要。LED-S 可以匹配 GP-S 刺激强度，因此是 GP-S 的潜在替代品。此外，与 GP-S 相比，LED-S 设备表面的强度均匀，对于标准刺激是静音的，并且可以产生延长的持续时间刺激，用于记录开-关 ERG。
