ENG検査におけるコンピューター分析-健常者を対象として-

Abstract

A quantitative analysis of eye movement with optokinetic and caloric nystagmus was undertaken in normal subjects using a digital computer. Fifteen parameters were established to differentiate nystagmus from artifacts. Eight of the parameters were used to diagnose the quick phase and the other 7 parameters were used to diagnose the slow phase. On OKN (optokinetic nystagmus), the velocity gain was calculated. The adaptation limits of slow phase velocity were a maximum slow phase velocity, while the velocity gain was over 0.8. In 20 normal subjects, the average slow phase velocity was 90°/sec (S. D.15.5). In the caloric test, the average maximum slow phase velocity was 32°/sec (S. D.11) and the average with the visual suppression test was 70% (S. D.10.5) in 31normal ears. In this analysis, the frequency of nystagmus was not necessarily reduced with visual suppression, so that the FFI (failure of fixation suppression index) was not a valid parameter.