Case example

Slo-mo aural explosion

A 4 year-old male Poodle was presented for tenderness of the left ear and pain when opening the mouth, as well as a left-sided head tilt.

CT findings

Image 1 + 2: Expansile lysis of left tympanic bulla with ring-like enhancement.
Image 3: Lysis of petrosal part of temporal bone, involving inner ear.
Image 4: Adjacent focal meningeal enhancement.


  • Left tympanokeratoma (aural cholesteatoma) with secondary reactive meningitis.

Learning points

  • Cholesteatomas more appropriately named tympanokeratoma due to origin from tympanic membrane.
  • Progressive hyperkeratosis creates the expansile character.
  • CT allows for characterization of ear disease and differentiation from otitis media or neoplasia.
  • Pathogenesis still controversial, but usually associated with chronic otitis media and expand with growth
  • Secondary infection can create a life-threatening situation with otitis interna and involvement of central nervous system.

More information

  • »Bilateral tympanokeratomas (cholesteatomas) with bilateral otisis media, unilateral otitis interna and acoustic neuritis in a dog«
    — Østevik et al., Acta Vet Scand. 2018 May; 60: 31
  • »Computed Tomography features of middle ear cholesteatoma in dog«
    — Travetti et al, Vet Radiol & Ultrasound 51(4) 2010; 374-379
  • »Aural cholesteatoma in 20 dogs«
    — Hardie et al., Vet Surg. 2008; 37(8); 763-70

Images courtesy of the AniCura Tierklinik Haar, Germany.