Evaluation of eustachian tube function using a portable device

The present paper investigates a portable eustachian-tube-function testing device by sonotubometry based on pure-tone sound transmission via the eustachian tube (ET). The measured results obtained by the proposed method were validated through comparison with the existing testing technique based on broadband sound inspection. The measurement results for the ET opening time (T_open) and the sound pressure difference in the ear canal between open and closed ETs (ΔL) obtained using pure-tone sounds with tonal frequency components of 7.0 and 9.5 kHz generally agreed with the results obtained by the existing technique with broadband testing sound.