Cholesteatoma: Diagnosis, Mastoid Surgery and Long-term Follow-up

Cholesteatoma is a progressively enlarging lesion of keratinising squamous epithelium in the middle ear and mastoid. Called a "tumour" but not a neoplasm — a benign lesion with persistent keratin accumulation and enzymatic bone erosion. Untreated, it can cause serious complications: labyrinthitis, facial palsy, meningitis, brain abscess.

Pathogenesis theories: 1) Retraction pocket theory (most accepted) — persistent retraction of pars flaccida or pars tensa (from Eustachian dysfunction) → keratin accumulates in the pocket. 2) Migration theory — external canal epithelium migrates through a perforation. 3) Metaplasia theory — middle ear mucosa undergoes squamous metaplasia from chronic inflammation. 4) Congenital — embryonic epidermal remnants (behind intact membrane).

Types: acquired primary (most common adult/older child; from pars flaccida retraction), acquired secondary (after perforation), congenital (behind intact membrane, early childhood).

Incidence: 6-10 per 100,000 per year; any age but most common in children and young adults. Slight male predominance. Risk factors: chronic middle ear disease, Eustachian dysfunction, recurrent otitis, cleft palate, Down syndrome.

Clinical course: early years asymptomatic or mild (ear discharge, mild conductive loss); progressively expands; ossicular destruction (incus → stapes → malleus); spread to labyrinth (sensorineural loss); facial canal erosion (palsy); tegmen erosion (intracranial spread).

Delayed diagnosis can lead to: labyrinthitis (vertigo, sensorineural loss), facial palsy, extradural/subdural abscess, brain abscess, lateral sinus thrombosis, meningitis. These are now rare but can be life-threatening if missed. We expand on the clinical framework in our otology and hearing centre.

Classic triad: chronic ear discharge (foul-smelling, persistent or recurrent; partial response to antibiotic drops), conductive hearing loss (ossicular destruction), retraction pocket or marginal perforation (white/yellow keratin debris on otoscopy).

Associated findings: ear pain (warning of complication — labyrinthitis, mastoiditis, intracranial spread), vertigo (labyrinth erosion — semicircular canal fistula), facial asymmetry/palsy (facial canal erosion), severe headache + fever (intracranial complication — emergency surgery).

Otoscopy/otomicroscopy: pars flaccida (Shrapnell) retraction pocket or keratin accumulation (most common), pars tensa retraction pocket (especially posterosuperior quadrant), marginal perforation, keratin debris, granulation tissue. Otomicroscopy is far more informative than routine otoscopy.

Audiometry: standard pure-tone + speech. Typical finding is conductive hearing loss (10-50 dB air-bone gap); advanced cases may show mixed or sensorineural (labyrinth involvement).

Imaging: high-resolution temporal bone CT (1 mm axial + coronal) — does not directly identify cholesteatoma (soft tissue density) but maps extent, bone erosion (tegmen, facial canal, semicircular canal, ossicles), mastoid pneumatisation. Critical for surgical planning.

MRI (DWI — diffusion-weighted): differentiates cholesteatoma (high signal) from granulation and fluid (low signal). Especially in paediatric cases, suspicion of residual/recurrent cholesteatoma — DWI MRI is increasingly preferred over routine second-look surgery.

Congenital cholesteatoma: white mass behind an intact membrane (anterosuperior quadrant), found incidentally or after otitis in a normal child; may lack discharge/conductive loss. Detected early — treatable by simple excision.

Surgical goals (in order of priority): 1) complete removal — otherwise recurrence is inevitable. 2) Dry, safe ear — no complication, no discharge. 3) Hearing restoration (often staged). 4) Anatomic preservation (when closed technique feasible).

Canal wall up (CWU) mastoidectomy: external canal posterior wall preserved. Steps: postauricular incision, cortical mastoidectomy (open mastoid air cells), posterior tympanotomy (facial recess) — access between middle ear and mastoid. Disease cleared in both. Ossicular reconstruction possible (PORP/TORP).

CWU pros: anatomy preserved (water and air exposure normal), small mastoid cavity (no annual cleaning), better potential hearing reconstruction, cosmetic (no visible cavity). Cons: some areas (attic, sinus tympani, retrofacial) hard to view — higher residual risk; planned second-look at 6-18 months commonly recommended; recurrence 10-25%.

Canal wall down (CWD, modified radical mastoidectomy): posterior canal wall removed; mastoid cavity and middle ear are exteriorised as a single broadened canal. Indications: extensive disease (mesotympanic posterosuperior, attic, mastoid), semicircular canal fistula, complex anatomy/small mastoid, extensive ossicular destruction, failed prior CWU, deaf ear (no useful hearing), difficult follow-up (elderly, comorbid, distant).

CWD pros: entire middle ear visible → lower residual disease (5-10%), single-stage often sufficient, ongoing inspection feasible. Cons: large external cavity — annual cleaning (debris), no water exposure (swimming, water ingress restricted), more limited hearing reconstruction, meatoplasty and mastoid obliteration needed to create a "good cavity".

Modified CWD with mastoid obliteration: classic open cavity reduced with cartilage, bone pâté, fascia, autogenous or allogeneic material; wide meatus kept. Pros: smaller, drier cavity, water exposure possible in some cases, better hearing outcome. Modern hybrid.

Endoscopic mastoidectomy: less invasive transcanal approach with 0 and 30/45 degree endoscopes. Effective in limited cholesteatoma (attic, mesotympanum). Complements microscope rather than replaces in extensive mastoid disease. More detail: cholesteatoma page.

Cholesteatoma causes conductive hearing loss via ossicular destruction (especially long process of incus, then stapes superstructure). Reconstruction timing: single-stage (in suitable cases) or 6-12 months later at second look. Staging rationale: first stage eradicates disease, second stage controls residual/new cholesteatoma + ossiculoplasty.

Materials: PORP (Partial Ossicular Replacement Prosthesis) — when stapes superstructure intact; titanium, hydroxyapatite, hybrid. TORP (Total Ossicular Replacement Prosthesis) — when superstructure absent (onto footplate). Autologous: incus interposition (patient's own incus sculpted and reinserted), cortical bone.

Outcomes: meaningful gain when air-bone gap closes to <20 dB. PORP 50-70% success (clinically meaningful closure); TORP 35-55%. Depends on ossicular status, middle ear mucosa health, Eustachian function, cavity type (CWU better than CWD).

Tympanoplasty: reconstruction often needed alongside cholesteatoma surgery — perforation, retraction, ossicular damage. Graft materials: temporalis fascia (classic), perichondrium, tragal cartilage, conchal composite cartilage. Cartilage prevents re-retraction (the original problem!) — thicker but more stable.

Safety first, hearing second: reconstruction only meaningful after disease control is assured. Reconstruction during active disease fails and adds risk.

Alternatives: active middle ear implant, bone conduction device (BAHA, BoneBridge) — particularly when CWD cavity precludes conventional aids.

Paediatric considerations: Eustachian function less mature, retraction and recurrence more common — reconstruction planning is cautious, often staged into adolescence.

Early postop: ear pack 1-2 weeks. Antibiotic drops (often with hydrocortisone) for 1-2 weeks after pack removal. No water exposure 4-6 weeks. Microscopic checks at 2, 6, 12 weeks.

Long-term: annual review — microscopic debris cleaning, residual/recurrent disease check. Discharge, pain, vertigo, facial asymmetry, hearing worsening require urgent evaluation.

Detecting residual disease: second-look surgery (6-18 months, classic for CWU), DWI MRI for non-invasive surveillance (modern alternative — favoured in paediatric cases). DWI sensitivity ~90+%, specificity ~90+%.

CWD care: annual cavity cleaning — patients become "cavity ear owners". If the cavity stays "dry and self-cleaning", less often (1-2 per year). A discharging cavity needs added care (topical antibiotic, acid-alcohol drops, debris removal).

Water protection: with CWD, swimming/diving forbidden; bath with ear protection (wax/silicon plug + headband). With CWU, if reconstruction is successful, limited exposure (sea, chlorinated pool — caution and review).

Hearing follow-up: annual audiogram; deterioration is a warning sign for residual disease or reconstruction failure.

Expectations: dry safe ear 85-95%; meaningful hearing gain 50-70%. Recurrence (true new cholesteatoma) 5-15% adults, 10-25% children. Early diagnosis and surgery → fewer complications, simpler operation, better outcome.

Quality of life: the surgical course is stressful; long-term follow-up commitment needed. Family and patient education — cholesteatoma is a chronic condition; "one and done" cure is uncommon. We share patient experiences on our patient testimonials.