Definition

Cholesteatoma is a type of skin cyst that is located in the middle ear and mastoid bone in the skull.

Alternative Names

Chronic ear infection - cholesteatoma; Chronic otitis media - cholesteatoma

Causes

Cholesteatoma can be a birth defect (congenital). It more commonly occurs as a result of chronic ear infection.

The eustachian tube helps equalize pressure in the middle ear. When it is not working well, negative pressure can build up and pull part of the eardrum (tympanic membrane) inward. This creates a pocket or cyst that fills with old skin cells and other waste material.

The cyst may become infected or get bigger. This can cause the breakdown of some of the middle ear bones or other structures of the ear. This can affect hearing, balance, and possibly the function of the facial muscles.

Symptoms

Symptoms include:

• Dizziness
• Drainage from the ear, which can be chronic
• Hearing loss in one ear
• Sensation of ear fullness or pressure

Exams and Tests

An ear exam may show a pocket or opening (perforation) in the eardrum, often with drainage. A deposit of old skin cells may be seen with a microscope or an otoscope, which is a special instrument to view the ear. Sometimes a group of blood vessels may be seen in the ear.

The following tests may be performed to rule out other causes of dizziness:

• CT scan
• Electronystagmography
• MRI scan

Treatment

Cholesteatomas very often continue to grow if they are not removed. Surgery is most often successful. However, you may need the ear cleaned by a health care provider from time to time. Another surgery may be needed if the cholesteatoma comes back.

Possible Complications

Complications may include:

• Brain abscess (rare)
• Erosion into the facial nerve (causing facial paralysis)
• Meningitis
• Spread of the cyst into the brain
• Hearing loss

When to Contact a Medical Professional

Contact your provider if ear pain, drainage from the ear, or other symptoms occur or worsen, or if hearing loss occurs.

Prevention

Prompt and thorough treatment of chronic ear infection may help prevent cholesteatoma.

References

Player B. Otitis media. In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 680.

Thompson LDR. Tumors of the ear. In: Fletcher CDM, ed. Diagnostic Histopathology of Tumors. 5th ed. Philadelphia, PA: Elsevier; 2021:chap 30.