Abstract
Electronystagmography not just enables a qualitative and quantitative analysis of nystagmus possible, but furthermore gives nystagmus findings of open eyes in the dark and closed eyes which cannot be observed by the unaided eyes.
This results is a marked increase in the detection ratio of pathological nystagmus, and this tendency can be strengthened further by taking ENG recordings when posture test are made.
At such times, it is very necessary that recordings not only of closed eyes but open eyes in the dark should be taken so as to increase the positive ratio of detecting pathological symptoms and to obtain nystagmus tracings that are less distorted than when the eyes are closed.
On the other hand, ENG from its principle does not record rotatory components, nor from the characteristic of the equipment is it adapted to record slow ocular movements, and it has also the fault that other types of bio-electric potential cause interference.
To compensate for these shortcomings a method was devised by employing an infrared television so as to observe the findings when the eyes are open in the dark in the same way as when the eyes are open in the light.
By combining this apparatus and ENG, all pathological findings that show up as ocular movements can be completely caught, and this is expected to open the way for future studies.
