title: Otologic manifestations of malignant osteopetrosis.
abstract: OBJECTIVE
  To determine the incidence of hearing loss and describe the neurotologic manifestations over time in a large series of patients with malignant osteopetrosis.
  
  
  METHODS
  Longitudinal study.
  
  
  METHODS
  Tertiary care referral center.
  
  
  METHODS
  Thirty-two patients, including 19 infants (< 1 yr of age at initial visit) and 13 children (aged 1-7.6 yr at initial visit), with autosomal recessive osteopetrosis were followed-up during a 10-year period from 1991 to 2001. The average length of follow-up was 2.5 years (range, 0-9.1 yr).
  
  
  METHODS
  Patients underwent annual otologic evaluations including clinical examination, audiologic evaluation (auditory brainstem response, pure-tone thresholds, speech discrimination scores, and tympanograms), and high-resolution computed tomography of the temporal bone.
  
  
  METHODS
  Incidence of hearing loss, otitis media, and facial paralysis. Serial changes in temporal bone anatomy by computed tomographic scan.
  
  
  RESULTS
  Twenty-six percent of infants' ears demonstrated hearing loss during the first year of life, and 78% of children's ears demonstrated hearing loss during the study period. Of the children's ears with hearing loss, 100% had a conductive component and 26% had an additional sensorineural component (mixed hearing loss); VIIIth nerve conduction was normal in 100% of infants and 78% of children. Five patients (16%) had unilateral facial nerve palsy. Common temporal bone findings included thickening and sclerosis of the calvarium; poor pneumatization of the mastoid bone; and narrowing of the external auditory canal, eustachian tube, and internal auditory canal.
  
  
  CONCLUSIONS
  Otologic manifestations are common in malignant osteopetrosis secondary to the formation of dense, brittle bone. Frequent findings include external auditory canal stenosis, otitis media, conductive and sensorineural hearing loss, and facial nerve paralysis.
authors: Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina 29425, USA. dozierts@musc.edu
authors: Thomas S
authors: TS
authors: Dozier
authors: Irenee M
authors: IM
authors: Duncan
authors: Alan J
authors: AJ
authors: Klein
authors: Paul R
authors: PR
authors: Lambert
authors: L Lyndon
authors: LL
authors: Key
mesh_terms: D002648:Child; D002675:Child, Preschool; D005158:Facial Paralysis / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006314:Hearing Loss, Conductive / Q000453:epidemiology / Q000209:etiology*; D006319:Hearing Loss, Sensorineural / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D010022:Osteopetrosis / Q000150:complications* / Q000000981:diagnostic imaging; D010033:Otitis Media / Q000453:epidemiology / Q000209:etiology*; D013701:Temporal Bone / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed