Comparative Study of Electrocochleography between Transtympanic and Ear Canal Recording Technique

Abstract

A comparative study was made on electrocochleography by the transtympanic and the ear canal recording technique in normal hearing subjects.
The results obtained were as follows:
The auditory whole nerve action potential (AP) recorded from the ear canal showed extremely low ampliitude but AP latency, wave form and threshold did not so differ significantly from the transtympanic recording technique.
Cochlear microphonics (CM) recorded from the ear canal also showed a low output potential as well as AP. Furthermore, there was a limitation of information from the cochlea because of a higher detection threshold of the CM and mixture of the electromagnetic induction wave,
Therefore, the transtympanic recording technique is more efficient than that of the ear canal recording technique.