Abstract
Studying the oscillatory potentials in diabetic retinopathy, the authors experienced several problems interpreting results of digital filtering. The main problem was the separation of the first potential from the a-wave, since their frequencies are within the same range. To improve the procedure of measuring implicit times and of calculating amplitudes, the filtering was started with a finite impulse response filter and followed by a fast Fourier transform. The power of the oscillatory potential was calculated by determining the dominant frequency in the Fourier transformed response and expressed in microwatts. A group of normal subjects was compared with a group of early diabetic retinopathy patients. It appears that even in pathological circumstances a quantitative expression of the oscillatory potential is possible.
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Van Der Torren, K., Groeneweg, G. & Van Lith, G. Measuring oscillatory potentials: Fourier analysis. Doc Ophthalmol 69, 153–159 (1988). https://doi.org/10.1007/BF00153696
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DOI: https://doi.org/10.1007/BF00153696