A Case of High Jugular Bulb Diverticulum Presenting with Ear Symptoms Associated with Posture Change

High jugular bulb refers to the condition in which the jugular bulb protrudes in the direction of the head, and cases where high jugular bulb protrudes in a notch-like shape toward the posterior part of the internal auditory canal are labelled as having a jugular bulb diverticulum. Jugular bulb diverticulum is rare, with few published case reports, but almost all published reports are of cases diagnosed after the onset of hearing loss or vertigo. The following mechanisms of inner ear damage caused by a jugular bulb diverticulum have been speculated: (1) secondary endolymphatic hydrops due to compression of the vestibular aqueduct and endolymphatic sac; (2) compression of the cochlear nerve and blood vessels in the internal auditory canal; and (3) direct compression of the cochlea, vestibule, and utricular labyrinthine membrane.