Modern electronystagmography for vestibulometry practice

The following problems of the practical use of electronystagmography (ENG) are examined in the article: direct and indirect ENG recording, types of amplifiers, determination of the time constant of the amplifier of the recording instrument, specific significance of the values of the time constant and amplification for the information content of the nystagmus indices, limits of the linear relation between eye movements and their recording on an instrument with a different amplification and time constant, calibration of eye movements and calibration of the instrument, effect of light on the value of the corneo-retinal potential, value of the angle of calibration of eye movements with fixation of the gaze in the middle position or only at the extreme points of the central angle, paper speed when recording nystagmus, and type of recorder pen. On the basis of an analysis of 4325 EOG and ENG new principles were established and appropriate recommendations were made for improving the quality and effectiveness of electronystagmography. With consideration of the established new facts the recommended technique of modern electronystagmography is presented.