Manometric determinations of pressure changes in the external auditory meatus caused by a patulous eustachian tube.

The pressure changes developing in the nasopharynx and in the external auditory canal during breathing at rest were examined by means of manometry in patients with patulous eustachian tubes and in healthy control subjects who were able to keep their eustachian tubes opened for prolonged periods of time. Findings demonstrated that pressure changes in the nasopharynx in both groups were practically the same, but pressure changes in the external auditory meatuses of the patients with patulous tubes were about one order greater than in the control group. This occurrence might be caused either by relaxation of the fibers of the tympanic membrane or by different degrees of opening of the eustachian tubes.