II. Definition

  1. Ankylosis between Stapes footplate and surrounding bone of the inner ear

III. Epidemiology

  1. Most often presents in middle-aged white women
  2. Gender predominance: Twice as common in women
  3. Age at onset: 30-50 years old
  4. Family History is present in 50% of cases
    1. Autosomal Dominant trait, with poor penetrance

IV. Pathophysiology

  1. Abnormal bone deposition at base of Stapes (footplate)
  2. Stapes fixed to oval window and unable to vibrate

V. Symptoms

  1. Gradual onset, painless, bilateral Hearing Loss
  2. Tinnitus

VI. Signs

  1. Conductive Hearing Loss or mixed Hearing Loss
  2. Hearing Loss usually limited to 50 decibels
    1. See Hearing Impairment Severity Scale
  3. Bilateral involvement is most common
  4. Disproportionately effects low frequencies most commonly
    1. Able to hear voices in noisy environments
  5. Normal Tympanic Membrane appearance

VII. Differential Diagnosis

VIII. Management

  1. Hearing Aid
  2. Sodium Fluoride
    1. May halt or retard progression
  3. Surgery: Stapedotomy or Stapedectomy
    1. Restore transmission with middle ear prosthesis
    2. Improvement in 95% of patients

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Related Studies

Ontology: Otosclerosis (C0029899)

Definition (MSHCZE) Onemocnění charakterizované přestavbou kostních částí vnitřního ucha s jeho poškozením (fixace, ankylóza třmínku). Projevuje se nepříjemnými šelesty a nedoslýchavostí a může vést (při oboustranném postižení) až k převodní hluchotě. Výraznou měrou se uplatňuje dědičnost a též hormonální vlivy (častější je u žen a poměrně často začíná v těhotenství či během kojení). Léčba je zejm. chirurgická. (cit. Velký lékařský slovník online, 2013 http://lekarske.slovniky.cz/ )
Definition (CSP) pathological condition of the bony labyrinth of the ear, in which there is formation of spongy bone; may cause bony ankylosis of the stapes, resulting in conductive hearing loss; cochlear otosclerosis may also develop, resulting in sensorineural hearing loss.
Definition (MSH) Formation of spongy bone in the labyrinth capsule which can progress toward the STAPES (stapedial fixation) or anteriorly toward the COCHLEA leading to conductive, sensorineural, or mixed HEARING LOSS. Several genes are associated with familial otosclerosis with varied clinical signs.
Concepts Disease or Syndrome (T047)
MSH D010040
ICD9 387.9, 387
ICD10 H80 , H80.9, H80.90
SnomedCT 155241009, 194383003, 11543004
English Otoscleroses, Otosclerosis, Otospongioses, Otospongiosis, OTOSCLEROSIS, Otosclerosis, unspecified, OTSC1, OTS, otosclerosis (diagnosis), otosclerosis, Otosclerosis NOS, Unspecified otosclerosis, Unspecified otosclerosis, unspecified ear, Otosclerosis [Disease/Finding], otoscleroses, OTOSCLEROSIS 1, Otosclerosis NOS (disorder), Otosclerosis (disorder), otospongiosis, Otosclerosis, NOS, Otospongiosis, NOS
Portuguese OTOSCLEROSE, Otosclerose NE, Otoesclerose, Otosclerose, Otospongiose
Spanish OTOSCLEROSIS, Otosclerosis no especificada, otoesclerosis, SAI, otoesclerosis, SAI (trastorno), Otoesclerosis, otoesclerosis (trastorno), otoesclerosis, otoespongiosis, Otosclerosis, Otospongiosis
German OTOSKLEROSE, Otosklerose, unspezifisch, Otosklerose, nicht naeher bezeichnet, Otosklerose, Otospongiose
Dutch niet-gespecificeerde otosclerose, otospongiose, Otosclerose, niet gespecificeerd, otosclerose, Otosclerose, Otospongiose
French Otosclérose, non précisée, OTOSCLEROSE, Otospongiose, Otosclérose
Italian Otosclerosi, non specificata, Otospongiosi, Otosclerosi
Japanese 詳細不明の耳硬化症, ショウサイフメイノジコウカショウ, ミミコウカショウ, ジコウカショウ, ショウサイフメイノミミコウカショウ, 耳硬化症, 耳硬化
Swedish Otoskleros
Czech otoskleróza, Otoskleróza, blíže neurčená, Otospongióza, Otoskleróza, otospongióza
Finnish Otoskleroosi
Russian OTODISTROFIIA, OTOSKLEROZ, OTOSPONGIOZ, ОТОДИСТРОФИЯ, ОТОСКЛЕРОЗ, ОТОСПОНГИОЗ
Korean 상세불명의 귀경화증, 귀경화증
Croatian OTOSKLEROZA
Polish Otoskleroza
Hungarian Otosclerosis, otosclerosis, nem meghatározott, Otospongiosis
Norwegian Otosklerose