title: Long-term follow-up of hearing loss in children and young adults with enlarged vestibular aqueducts: relationship to radiologic findings and Pendred syndrome diagnosis.
abstract: OBJECTIVE
  To describe the long-term audiologic findings in pediatric patients with enlarged vestibular aqueducts (EVAs). The relationship between the hearing loss (HL) and the dimensions of the EVA, enlarged endolymphatic duct (EED), or enlarged endolymphatic sac (EES) was also investigated. The influence of a Pendred syndrome (PS) diagnosis on the audiologic phenotype was also examined.
  
  
  METHODS
  Retrospective analysis of case notes and imaging records, including measurement of the dimensions of the EVA, EED, and EES.
  
  
  METHODS
  Tertiary referral center.
  
  
  METHODS
  Twenty-seven patients (21 female, 6 male) had an EVA in at least one ear. Eighty-five percent had bilateral enlargements. Median age at onset of follow-up was 5.0 years, and median follow-up was 9.7 years.
  
  
  METHODS
  Hearing thresholds at the start and end of follow-up, rate of progression of HL, history of sudden drops in hearing.
  
  
  RESULTS
  : All ears with an EVA had HL. Average HL at the start and end of follow-up was severe. Thirty-seven percent of patients had progressive HL, and 33% reported sudden drops in hearing. Progression was significantly associated with a history of sudden drops. PS patients had worse hearing at the end of follow-up as compared with nonsyndromic patients. There was no evidence of a relationship between the dimensions of the EVA, EED, or EES and the severity or progression of HL.
  
  
  CONCLUSIONS
  Patients with EVAs should be advised to avoid known trigger factors for sudden drops in hearing (e.g., minor head trauma). A diagnosis of PS may be associated with a worse audiologic prognosis.
authors.affiliation: Department of Paediatric Audiovestibular Medicine, Royal National Throat, Nose and Ear Hospital, London, United Kingdom. ian.colvin@blueyonder.co.uk
authors.forename: Ian B
authors.initials: IB
authors.lastname: Colvin
authors.forename: Timothy
authors.initials: T
authors.lastname: Beale
authors.forename: Katherine
authors.initials: K
authors.lastname: Harrop-Griffiths
mesh_terms: D001309:Auditory Threshold; D001692:Biological Transport; D018450:Disease Progression; D004711:Endolymphatic Duct / Q000473:pathology; D004712:Endolymphatic Sac / Q000473:pathology; D005260:Female; D034381:Hearing Loss / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D006319:Hearing Loss, Sensorineural / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007037:Hypothyroidism / Q000235:genetics; D008279:Magnetic Resonance Imaging; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics; D012189:Retrospective Studies; D000076988:Sulfate Transporters; D013577:Syndrome; D014057:Tomography, X-Ray Computed; D014723:Vestibular Aqueduct / Q000000981:diagnostic imaging / Q000473:pathology*
chemical_list: D026901:Membrane Transport Proteins; C085609:SLC26A4 protein, human; D000076988:Sulfate Transporters