Computerized electro-nystagmography.

A computerized electro-nystagmography (ENG) system was developed on the basis of a new idea for the performance of ENG. In this system, all the functions of conventional ENG was performed by a personal computer (PC) except for the initial setting of an analog amplifier. The eye movement signals from the ENG amplifier were displayed on the graphic screen and recorded on a magnetic or magneto-optical disc. By using a special graphic screen, eye movements, even fine nystagmus, can be more clearly observed than they can on the PC's conventional graphic screen. Examiners can select the most suitable display condition according to the specific purpose(s) of the ENG examination. As a laser printer prints the recorded eye movements simultaneously with data sampling, we can observe eye movements in the same manner as on the recorded paper of a conventional ENG. Moreover, this system has a very powerful function for the analysis of such nystagmus responses as caloric test, VOR test and optokinetic nystagmus and it can be gotten at a lower cost than conventional ENG. These technical and economical features indicate that the computerized ENG system is a very useful and convenient device for observing, recording and analyzing ENG examinations.