title: Hemorrhage in the endolymphatic sac: a cause of hearing fluctuation in enlarged vestibular aqueduct.
abstract: OBJECTIVE
  Most of the patients with enlarged vestibular aqueduct (EVA) experience sudden hearing deterioration, but the exact mechanism is unclear. We analyzed magnetic resonance (MR) images and the cellular components of endolymph obtained from the endolymphatic sac in patients with EVA, in order to demonstrate the cause of sudden hearing loss.
  
  
  METHODS
  A total of 25 patients (50 ears) with EVA, who had severe to profound hearing loss, were included in this retrospective clinical study. MR examinations were performed by a 3.0-T MR system using an 8-channel sensitivity-encoding head coil. We analyzed endolymphatic fluid harvested from the endolymphatic sac during cochlear implantations in four patients.
  
  
  RESULTS
  The area of low signal intensity in the endolymphatic sac was observed on T2-weighted MR images for 15 of 50 ears. This area was observed more frequently in patients who experienced recent sudden hearing loss (10/12, 83%) than those with stable hearing (5/38, 13%)(Fisher's exact test, p<0.001). In addition, this area showed high signal intensity on fluid attenuated inversion recovery images. Cytologic analysis of the aspirated endolymph from the endolymphatic sac in the patients with this area revealed many erythrocytes.
  
  
  CONCLUSIONS
  Our data suggests that hemorrhage in the endolymphatic sac could be a cause of sudden hearing deterioration in patients with EVA.
authors.affiliation: Department of Otology, Hana ENT Hospital, Seoul, South Korea.
authors.forename: Minbum
authors.initials: M
authors.lastname: Kim
authors.forename: Jinna
authors.initials: J
authors.lastname: Kim
authors.forename: Sung Huhn
authors.initials: SH
authors.lastname: Kim
authors.forename: Sang Cheol
authors.initials: SC
authors.lastname: Kim
authors.forename: Ju Hyun
authors.initials: JH
authors.lastname: Jeon
authors.forename: Won Sang
authors.initials: WS
authors.lastname: Lee
authors.forename: Un-Kyung
authors.initials: UK
authors.lastname: Kim
authors.forename: Hee Nam
authors.initials: HN
authors.lastname: Kim
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Choi
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004710:Endolymph; D004712:Endolymphatic Sac; D004912:Erythrocytes / Q000473:pathology; D005260:Female; D003639:Hearing Loss, Sudden / Q000209:etiology*; D006470:Hemorrhage / Q000150:complications*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D014723:Vestibular Aqueduct / Q000473:pathology*