System and process for recording erg, perg and vep multifocal electrofunctional responses in real-time

Abstract

Process and system for determining the topography of bioelectric response signals of a visual system including a patient's retina, optical nerve or a projection thereof at the level of the central cortex, following visual stimulation through a surface arranged in front of the patient's eye. An image which comprises a plurality of cells is displayed as stimuli, each cell being activated or deactivated according to a corresponding digital time function represented by a cyclical succession of binary m-sequences of duration (T) formed from a plurality of activation symbols (N). Symbols N have a duration (Ts), and the m-sequences of the various cells are obtained cyclically from a mother m-sequence. The process determines the total bioelectric response of the visual system. The response associated with each cell is determined by the total response of the visual system using a cross-correlation with a suitable translated version of a mother m-sequence. Calculation of the response of each cell is updated at the end of each symbol time (Ts), thereby making it possible to follow the evolution of the calculated response of each cell in real-time, without awaiting the end of an m-sequence.