2025 Volume 118 Issue 7 Pages 497-501
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.
We report the case of a 38-year-old female patient who visited our hospital with the chief complaint of transient ear symptoms associated with postural changes. At first, because the ear symptoms associated with postural changes, it was suspected that the patient had a patulous eustachian tube, but the eustachian tube function was subsequently confirmed as being normal. Eventually, the diagnosis of a high jugular bulb diverticulum was made based on the findings of CT and MRI. We suspect that the ear symptoms were caused by the transmission of venous pressure or intracranial pressure to the endolymph via the vestibular aqueduct.
