Sonotubometric Assessment for Severity of Patulous Eustachian Tube

    loading  Checking for direct PDF access through Ovid



To investigate the relationship between the morphological patency of the eustachian tube (ET) and sound transmission via the ET.

Study Design:

Retrospective chart review and model experiment.


Tertiary referral center.


A total of 56 ears of 28 patients (9 men and 19 women, aged from 12 to 82 yr, mean 40.4 ± 21.5 yr) who underwent sonotubometric measurement using postural change as well as computed tomography (CT) of the ET in the sitting position, including 26 ears with definite patulous ET, 9 ears with possible patulous ET, and 21 ears without patulous ET.


Commercial equipment for sonotubometry (JK-05A; RION Co., Ltd., Kokubunji, Tokyo, Japan) was used in the following two investigations. Retrospective survey: sound patency of 7 kHz band noise via the ET was assessed by comparison of acoustic transfer function via the ET in the sitting and forward-bending positions. Sound patency via the ET was compared with morphological patency of the ET (cross-sectional area in the narrowest portion) assessed by three-dimensional CT of the ET in the sitting position. Model experiment: effect of the ET caliber on the acoustic transfer function was examined using a simple model constructed with two truncated syringes with silicone barrels and a narrow connecting tube.


Sound patency assessed by sonotubometry was well correlated with the cross-sectional area at the narrowest portion of the ET in the sitting position (r = 0.786, p < 0.001). Correlation between the sound patency via the narrow tube and the caliber of the tube was also confirmed by the model experiment.


Sound patency assessed by sonotubometry using 7 kHz band noise could be useful to predict the morphological severity of patulous ET.

Related Topics

    loading  Loading Related Articles