title: Large jugular bulb diverticulum invading the internal auditory canal.
abstract: OBJECTIVE
  We report, with neuro-otologic findings, a very rare case of a large jugular bulb diverticulum eroding the internal auditory canal (IAC).
  
  
  METHODS
  We present the imaging and functional studies of a 29-year-old woman in whom a large jugular bulb diverticulum on the left side was found incidentally.
  
  
  RESULTS
  Imaging studies revealed a normal external auditory canal, middle ear, and inner ear, but a large jugular bulb diverticulum extending superiorly on the left side had eroded the IAC from below and behind with destruction of the petrous bone. Caloric responses and facial movements were normal. Vestibular evoked myogenic potentials with bone conduction stimuli were absent on the left, indicating dysfunction of the left inferior vestibular system.
  
  
  CONCLUSIONS
  This is the first report in the English-language literature of detailed imaging and functional findings in a very large diverticulum invading the IAC. Vestibular evoked myogenic potentials were useful in uncovering subclinical inferior vestibular system dysfunction in the jugular bulb diverticulum invading the IAC.
authors.affiliation: Department of Otolaryngology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Chisato
authors.initials: C
authors.lastname: Fujimoto
authors.forename: Ken
authors.initials: K
authors.lastname: Ito
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Ishimoto
authors.forename: Shinichi
authors.initials: S
authors.lastname: Iwasaki
mesh_terms: D000328:Adult; D003287:Contrast Media; D003937:Diagnosis, Differential; D007758:Ear, Inner / Q000098:blood supply* / Q000473:pathology; D005260:Female; D019786:Gadolinium DTPA; D006314:Hearing Loss, Conductive / Q000175:diagnosis / Q000209:etiology*; D006801:Humans; D033162:Incidental Findings; D007601:Jugular Veins / Q000000981:diagnostic imaging; D018810:Magnetic Resonance Angiography; D010579:Petrous Bone / Q000473:pathology; D014057:Tomography, X-Ray Computed; D014724:Vestibular Function Tests; D000160:Vestibulocochlear Nerve Diseases / Q000175:diagnosis / Q000209:etiology*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA