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Cochlear anomalies (classification)

Cochlear anomalies are a variety of congenital anomalies which, depending on the exact time at which an insult occurs during embryogenesis, may have different manifestations. Terminology is often used imprecisely leading to confusion not only among clinicians, but also in the literature.


A classification first proposed in 1987 by Jackler et al. 2 has become widely accepted (with various modification), which divides congenital cochlear anomalies according to the timing of the developmental arrest. 

Conveniently starting at 3rd week till the end of 7th week of gestation, an insult during each subsequent week results in a distinct inner ear abnormality:

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Article information

rID: 9557
System: Head & Neck
Synonyms or Alternate Spellings:
  • Jackler's classification of cochlear anomalies
  • Jackler classification of cochlear anomalies
  • Classification of cochlear abnormalities
  • Classification of congenital cochlear abnormalities
  • Cochlear anomalies (classification)
  • Cochlear anomalies Jackler classification
  • Cochlea anomaly

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Cases and figures

  • Case 1: bilateral Mondini malformations
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  • Case 2: cochlear aplasia
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