Shan A, Ward BK, Goman AM, et al. - Researchers conducted this investigation to determine the prevalence of eustachian tube dysfunction (ETD) in US adults. ETD is a common diagnosis for conditions in which the eustachian tube is unable to perform its functions properly, resulting in symptoms including hearing loss, aural fullness, otalgia and autophony. It occurs with a variable severity range between two distinct (obstructive and patulous) subtypes, and individuals can fluctuate along this spectrum of disease, even between subtypes. There is no clear understanding of the precise causes of ETD, but there are correlations with inflammatory disease. ETD is diagnosed as indicated by combining clinical history, physical examination, tympanometry, audiometry and other tests. In terms of medical history and/or evidence of negative middle ear pressure, a recent clinical consensus statement identified obstructive ETD.