cholesteoma

Introduction

Infiltrate of keratinizing squamous epithelium & cholesterol in the middle ear.

Etiology

• generally results from chronic otitis media
• congenital in rare cases

Pathology

• chronic eustachian tube dysfunction can result in recurrent otitis media
  • if persistent, can result in tympanostomy tube placement &/or chronic otitis media with tympanic membrane retraction & cholesteoma
• cholesteoma is a collection of keratinized epithelial debris in retraction pockets of the tympanic membrane
• may impede tympanic membrane's ability to vibrate
• squamous metaplasia or squamous epithelium-lined cyst formation may extend into the mastoid & erode surrounding bone
• cyst may become secondarily infected & erode adjacent bone
• disruption of ossicles
• perforated tympanic membrane at the edge or margin can cause loss of the protective barrier of the annulus fibrosis

Clinical manifestations

• fullness in ear
• earache
• headache
• conductive hearing loss
• otoscopy
  • keratinized debris above or at the superior aspect of the tympanic membrane
  • chronic suppurative discharge from the middle ear through a perforated tympanic membrane (frequently at the margin)
  • pearly white to gray mass behind the tympanic membrane visible with otoscope
  • tympanic membrane appears retracted & concave, with a prominent lateral process of the malleus
  • tympanic membrane may be immobile on pneumatic otoscopy

Radiology

• erosion of bone (ear ossicles)
• enlargement of middle ear
• opacification of mastoid air cells

Complications

• superinfection (chronic suppurative otitis media)
• erosion of the ear ossicles

Management

• consult ENT

More general terms

• abnormal morphologic structure (malformation)