Week 4 - Cholesteatoma Flashcards
What is a cholesteatoma?
ME mass described as a cyst or tumour (noncancerous)
- epidermal inclusion cyst formed from stratified squamous epithelium
If cholesteatomas are non-cancerous, what’s the danger?
They can erode ossicles and spread to invade and damage surrounding tissues
What are the 2 classifications of cholesteatomas?
- Acquired (Primary or Secondary)
2. Congenital
What is a congenital cholesteatoma composed of?
Residual embryonic cells trapped in the ME
- squamous epithelial cells that produce keratin
- appears as a white mass medial to normal TM in ME cavity
What is the prognosis of congenital cholesteatoma dependent on?
Intact TM and no other otological issues
What two things can an acquired cholesteatoma develop from?
TM retraction or TM perforation
- allow skin and other debris to enter ME
- usually present with hx of poor ET function and chronic OM
What does the cyst-like pouch of an acquired cholesteatoma consist of?
- Dead and viable squamous epithelial cells
- Keratin shed by viable cells
- Enzymes that erode bone
- Cholesterol crystals
- Bacteria
Describe the two types of acquired cholesteatoma
Primary - TM retraction that accumulates epithelium and debris
Secondary - Result of migration of epithelium and debris through a perforation in the TM
What is otorrhea?
Ear drainage/discharge
T/F: A primary acquired cholesteatoma will always remain attached at the point of origin
False: It can eventually pinch off and continue to grow, forming a true cholesteatoma
What are 2 common sites for an acquired cholesteatoma to originate and which part of the ME do they move into?
Pars flaccida into posterior and anterior epitympanum (superior region of ME)
Posterior pars teens into mesotympanum
What are some of the complications caused by cholesteatomas?
- ME - erosion of ossicles and walls
- Posterior extension into the mastoid
- Superior invasion into brain cavity causing meningitis & abscess
- Medial wall - erosion of bony labyrinth causing sudden vertigo or sudden SNHL
- inferior - complication with facial nerve
What symptoms during a case hx might indicate cholesteatoma?
- fullness or pressure in the ear
- hearing loss
- otorrhea (drainage, possibly malodorous)
- otalgia (pain behind/in ear)
- dizziness or vertigo
- muscle weakness on one side of the face
What might a cholesteatoma show up as during a routine ax?
Audiometry: normal, conductive or mixed HL
Immitance: vary from normal to abnormal
How are cholesteatomas managed (from our perspective)?
Amplification
Aural rehabilitation
How are cholesteatomas managed in general?
- Possibly start by cleaning the ear (debridement) and antibiotics (goal to reduce pain, stop drainage, and control infection)
- Surgery to protect the patient from serious complications (goal to preserve or restore facial function and hearing)
Cholesteatoma surgery might be 1- or 2-steps. What might the follow-up revision be for with a 2-step surgery?
- Reconstruction to rebuild the walls of the ME or canal, reduce size of mastoid cavity, facial nerve repair, ossicular repair/replacement
- Removal of recurrence of cholesteatoma
Cholesteatoma surgery varies with the extent of the disease and degree of pre-operative HL. What are two approaches?
Tympanoplasty
- removal of cholesteatoma through TM
- rare, d/t the aggressive nature of the cholesteatoma
Mastoidectomy
- mastoid bone explored to remove any cholesteatoma that involves the bone and ME
What are the 2 basic types of Mastoidectomy?
- Canal-wall-up (CWU)
- posterior wall of external canal intact
- no mastoid cavity requiring cleaning, but higher risk of recurrence - Canal-wall-down (CWD)
- removal of bony partition b/w external canal and mastoid
- more extensive
What is a Canal Wall Down Modified Radical Mastoidectomy?
- less extensive and most common
- ME cavity left intact
- TM and/or ossicles retained or repaired
- variable degree of post-op conductive or mixed HL
What are some of the disadvantages of a Canal Wall Down Mastoidectomy?
- larger than normal canal opening and large open cavity (mastoid bowl)
- accumulation of debris in exteriorized mastoid cavity -> see doctor several times a year for cleaning
- Plugs when swimming, and vertigo in cold or hot water
- Chronic otorrhea resistant to tx
- hearing problems
Patients with no residual hearing and an ear that cannot be kept dry may have a Canal Wall Down Radical Mastoidectomy. What is removed in this surgery?
- extensive removal of bony structures, so ME, canal and mastoid cavity form single space
- TM and ossicles removed
- total exteriorization of ME, attic, and mastoid cavity and obliteration of ET
- Conductive/Mixed HL with max conductive component
What are some of the problems with amplification after a mastoidectomy, and what are some solutions?
Problems:
- large post-operative meatus -> altered resonance frequency
- inadequate aeration d/t occlusion
Alternatives:
- Bone conduction aids
- Reconstruction of mastoid cavity and EAM to reduce size and improve function
- high rate of dry ears and HL remains
