Cholesteatoma (Part 2)

Posted on May 14, 2015 Updated on May 22, 2015

Histopathology:

Macroscopic:

Cyst like structure in ME cleft that contains pale debris

Microscopic: 

• Fully differentiated stratified keratinizing squamous epithelium (capsule/ matrix)
• A nuclear keratin squamous epithelium (core)
• Epidermal Langerhans cells
• FB granuloma/ FB Giant cells
• Polyps
• Granulation tissue

How does squamous epithelium in cholesteatoma differs from skin? [viva]

• Absence of skin appendages ( glands/ hair follicles)

Different types of operation for cholesteatoma: 

Canal wall up procedure :

• Atticotomy
• Atticoantrostomy
• Cortical mastoidectomy
• Combined approach tympanoplasty

Canal wall down procedure :

• Modified radical mastoidectomy
• Radical mastoidectomy

Causes of persistent ear discharge post mastoidectomy:

• Infection
• Residual
• Recurrence
• High facial ridge
• Granulation tissue/ mastoid cavity not well epithelialized

Sites of residual cholesteatoma/ difficult areas of cholesteatoma:

1. Facial recess
2. Sinus tympani – area medial to facial nerve.

To overcome: also do anterior tympanotomy for better access.

1. Sinodural angle
2. Mastoid tip
3. Zygomatic root
4. Anterior epitympanum – due to head of malleus blocking the view (posterior tympanotomy access)

Difficulty/problem in Down syndrome:

1. Atlantoaxial dislocation
2. Heart disease
3. Short neck, macroglossia – difficult in anaesthesia
4. Narrow airway, reduced tone

Why do Down’s syndrome have persistent discharging ear?

1. Unable to complain
2. Small EAC
3. ET dysfunction – patulous ET ( no angle)
4. A/w cleft lip and palate
5. Difficult to cooperate for ear toilet and examination 

Cholesteatoma

Posted on May 14, 2015 Updated on May 22, 2015

Definition: (Abramson et al, 1977)

Points to mention: [viva]

• 3 dimensional epidermal and connective tissue structure
• Forming a sac
• Conforming the middle ear cleft ( middle ear, attic, mastoid)
• Capacity for progressive and independent growth involving the underlying bone and replacing the middle ear mucosa
• Tendency to recur

 

Classification:

1. Congenital
2. Acquired

• Primary (no previous h/o ear infection)
• Secondary (previous h/o  ear infection)

Congenital cholesteatoma aka: epidermoid cyst

Definition:

Squamous epithelial cyst that can arise anywhere within the temporal bone

LEVENSON CRITERIA (5)

1. White mass medial to TM
2. Normal pars tensa and pars flaccida
3. No history of otorrhea or perforation
4. No history of previous ear surgery
5. Prior bouts of OM not ground for exclusion

Theories for development of Cholesteatoma (6) [viva]

1. Congenital cell rests ~ epidermoid formation in the anterior epitympanic area in the developing fetal middle ear
2. Metaplasia of middle ear epithelium ~ squamous cell metaplasia in the ME epithelium in patients with cholesteatoma
3. Papillary ingrowth through an intact TM at the Prusak space.

Why Prusak space? Answer: Poor ventilation in the area.

4. Invagination of epithelium through pre-existing retraction  pocket or perforation

– most widely accepted theory

– obstruction of Eustachian tube causing impaired ME ventilation —> TM retracted and forming retraction pocket. Continuous desquamation and keratin accumulation leads to cholesteatoma formation.

5. Implantation theory

– iatrogenic: grommet insertion/ Tympanoplasty –> implantation of squamous cell into ME

6. Epithelial invasion theory

– invasion of skin from meatal wall through marginal or attic perforation

Management of attic cholesteatoma [viva]

– able to see fundus: conservative management / ear toileting

– not able to see fundus: do PTA and HRCT

PTA shows >40dB HL: possible ossicular chain involvement

HRCT : anatomical/ surgical landmark & disease extent

• Mastoid pneumatization – well pneumatization/ sclerotic
• Facial nerve dehiscence
• Ossicular disruption/ erosion
• Tegmen tympani/mastoidea breach
• Lateral SCC erosion

*** pictures are not mine. I googled them.