A flexible automated data acquisition system for ophthalmic electrophysiology

An automated system for performing VER, ERG and EOG measurements has been developed and is now in clinical use. Considerable effort has been made to retain the flexibility of non-automated systems while providing an easily followed procedure for standard tests which can be undertaken by staff with minimal training. Clinical experience has shown that the standard parameters for data acquisition which are optimal for normal subjects are not always suitable for patients who are uncooperative or have poor vision. These parameters are under software control and can be amended interactively if necessary. The five main functions of the software, namely data acquisition, data selection and commentary, report generation, patient database operation and waveform archiving are written as separate modules and called as required. During data acquisition the software rejects gross artefacts and in the case of EOG's warns of patient non-cooperation. After an ERG or VER has been acquired the operator identifies features in the waveforms and the computer measures them whereas for EOG's the measurement process has been automated. When the waveforms are subsequently reviewed by the operator they are presented in a logical sequence, a sequence which does not depend on the order in which they were acquired, and this sequence is maintained when they are printed out later in the completely automated report phase.