Measurement of the micro-electroretinogram and component analysis.

The authors propose a new technique for detecting micro-electroretinograms (muERG) which uses light-emitting diode (LED) stimulation and frequency analysis. The advantage of this method is the applicability of linear system analysis to a muERG obtained by partial stimulation of a computer-controlled waveform. The paper discusses two basic techniques for detecting the muERG. One is Fourier analysis of a synchronised ERG obtained by sine-wave stimulus, and the other is correlation analysis using a random stimulus. The results of the two methods are compared, and the usefulness of the proposed method is indicated; the muERG is analysed by means of a model consisting of five components of a second-order transfer function with delay. Functions of the central and peripheral areas of the retina could be analysed in more detail by this technique.