Shwetar Yousif, Lalush David, McAnany Jason, Jeffrey Brett, Haendel Melissa
Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, Chapel Hill, NC, United States.
Department of Ophthalmology and Visual Sciences, University of Illinois Chicago, Chicago, Illinois, United States.
medRxiv. 2025 Jul 27:2025.07.25.25331915. doi: 10.1101/2025.07.25.25331915.
To provide a conceptual understanding of the continuous and discrete wavelet transforms (CWT, DWT) for clinical electroretinography (ERG) analysis, and how these methods uncover time-frequency features that complement traditional time-domain analysis.
A technical overview without the use of mathematical formula describing the basics of CWT and DWT and implementation considerations. We also review an example of four standard ISCEV ERG recordings from a healthy male (between 30-34 years of age) and a male (between 15-19 years of age) with complete congenital stationary night blindness (CSNB).
Wavelet analysis uncovered time-frequency signatures absent in raw traces. In light-adapted flicker, the normal ERG showed a ~30 Hz response with harmonics up to 90 Hz, whereas CSNB was largely attenuated. For LA 3 and dark-adapted flashes, normal CWTs concentrated energy < 100 Hz between 0.04-0.08 s, while CSNB demonstrated lowered or almost absent energy profiles in comparison. DWT indices exhibited a similar pattern, with normal recordings demonstrating high energy responses early in the 7, 15, and 29 Hz frequency bands, while CSNB registered markedly lower values.
CWT and DWT provide complementary and objective insight into ERG responses. Open-source MATLAB toolkit and step-by-step tutorial provided herein lower technical barriers and enable use by the broader community.
提供对用于临床视网膜电图（ERG）分析的连续和离散小波变换（CWT、DWT）的概念性理解，以及这些方法如何揭示补充传统时域分析的时频特征。
进行技术概述，不使用数学公式描述CWT和DWT的基础以及实施注意事项。我们还回顾了一名健康男性（30 - 34岁）和一名患有完全性先天性静止性夜盲（CSNB）的男性（15 - 19岁）的四个标准国际临床视觉电生理学会（ISCEV）ERG记录的示例。
小波分析揭示了原始记录中不存在的时频特征。在明适应闪烁中，正常ERG显示出约30 Hz的响应，谐波高达90 Hz，而CSNB在很大程度上减弱。对于明适应3和暗适应闪光，正常CWT在0.04 - 0.08秒之间将能量集中在< 100 Hz，而相比之下，CSNB的能量分布降低或几乎不存在。DWT指数呈现出类似的模式，正常记录在7、15和29 Hz频段早期显示出高能量响应，而CSNB记录的值明显较低。
CWT和DWT为ERG反应提供了互补且客观的见解。本文提供的开源MATLAB工具包和分步教程降低了技术障碍，使更广泛的群体能够使用。
