Meniere's Disease (Ménière Disease)

Definition & Overview

1. Episodic spontaneous vertigo (lasting 20 minutes to several hours)
2. Fluctuating sensorineural hearing loss (SNHL)
3. Tinnitus (typically low-pitched "buzzing" or "roaring")
4. Aural fullness/pressure

• Cummings Otolaryngology Head and Neck Surgery, p. 3034
• K.J. Lee's Essential Otolaryngology, p. 76

Etiopathology

Histopathological Hallmark

Mechanism of Endolymph Overaccumulation

Inadequate absorption of endolymph by the endolymphatic sac leads to hydrops. The endolymphatic duct may act as a regulatory valve. Experimental animal models confirm that surgical disruption of the endolymphatic sac induces hydrops. Imaging shows hypoplasia of the endolymphatic sac and duct, and reduced vestibular aqueduct size in MD patients, with these anatomic features developing as early as age 3 years.

How Attacks Are Generated (Schuknecht's Membrane Rupture Theory)

• Acute hearing loss
• Vertigo (acute vestibular paralysis) Membrane healing restores normal ionic milieu, terminating the attack. Repeated episodes cause cumulative damage, explaining progressive hearing loss.

Etiological Theories

The etiology is likely multifactorial, representing the final common pathway of multiple injuries. Meniere's disease may not be a single homogeneous entity.

• Cummings Otolaryngology, Etiology of Ménière Disease section, pp. 3208-3209

MRI Finding (Gadolinium-Enhanced)

Diagnosis

• Two or more spontaneous episodes of vertigo, each lasting 20 min to 12 hours
• Audiometrically documented low-to-mid frequency SNHL in the affected ear on at least one occasion
• Fluctuating aural symptoms (hearing, tinnitus, or fullness) in the affected ear
• Not better accounted for by another vestibular diagnosis

• Cochlear hydrops: Fluctuating SNHL + tinnitus, no vertigo
• Vestibular hydrops: Episodic vertigo + aural fullness, no hearing loss
• Lermoyez syndrome: SNHL/tinnitus worsen pre-attack, then paradoxically improve when vertigo begins
• Tumarkin crisis (drop attack): Sudden fall without loss of consciousness; occurs in late disease

Management

1. Lifestyle Modifications (First Line)

• Low-sodium diet (< 1500-2000 mg/day) - reduces endolymph production
• Avoidance of caffeine, alcohol, and smoking
• Stress reduction
• Adequate sleep, regular exercise

2. Medical Management

No therapy to date has been proven to be effective for treatment of the hearing loss in Meniere's disease. - Cummings, p. 3034

3. Intratympanic (IT) Therapies

• Less destructive; preserves hearing
• Itoh & Sakata (1987): 4-5 weekly injections of 2 mg dexamethasone - vertigo relief in 80%, tinnitus reduction in 74%
• Variable protocols exist; ablative surgery avoided in 81-91% of patients
• Preferred first when hearing preservation is priority

• Selectively destroys vestibular hair cells (type I > type II)
• Highly effective for vertigo control (>90%)
• Risk of sensorineural hearing loss (titrated dosing minimizes this)
• Used in refractory cases with serviceable hearing or prior to surgical ablation

4. Surgical Management

• Endolymphatic sac decompression/shunting (ELS): Decompresses the sac ± mastoid-sac or subarachnoid shunts; results comparable to placebo in blinded RCTs but still widely performed
• Selective vestibular neurectomy (retrolabyrinthine, middle cranial fossa, retrosigmoid): Cuts vestibular nerve while preserving cochlear branch; high vertigo control (~90%), hearing preservation in most

• Labyrinthectomy (transmastoid): Destroys cochlea + vestibule; definitive vertigo control; use when no serviceable hearing
• Translabyrinthine 8th nerve section: Sacrifices all hearing; rarely used today

• K.J. Lee's Essential Otolaryngology, p. 76-77
• Cummings Otolaryngology, pp. 3034-3035

Management Summary Flowchart

Diagnosis confirmed
      ↓
Lifestyle (low-Na, diuretics, vestibular suppressants for attacks)
      ↓ [Refractory vertigo]
IT Dexamethasone (hearing preservation priority)
      ↓ [Still refractory]
IT Gentamicin
      ↓ [Still refractory, useful hearing]
Endolymphatic sac surgery OR Vestibular neurectomy
      ↓ [No useful hearing]
Labyrinthectomy

Prognosis

• Spontaneous remission occurs in ~60% of patients
• Natural history is unpredictable - high inter-episode variability
• Bilateral involvement in up to 50% within 20 years
• Progressive hearing loss to moderate-severe level in most; profound loss is rare

Recent Evidence Update

• A 2026 network meta-analysis (PMID 41194325) comparing IT to surgical management in refractory Meniere's shows IT gentamicin and surgical approaches have comparable vertigo control; surgical options carry higher morbidity
• A 2025 systematic review on Tumarkin drop attacks (PMID 39428593) highlights that drop attacks remain difficult to manage and may require IT gentamicin or surgical ablation
• A 2026 systematic review on endolymphatic sac surgery (PMID 41673972) shows continued evolution of sac surgery techniques, though efficacy remains debated

Otosclerosis

Definition

• Cummings Otolaryngology Head and Neck Surgery (Ch. 146)
• Robbins, Cotran & Kumar Pathologic Basis of Disease

Epidemiology

Etiology & Risk Factors

1. Genetics: Autosomal dominant with variable penetrance (25-40%). Multiple loci implicated (OTSC1-OTSC10, COL1A1 mutations). ~40-50% of cases are sporadic.
2. Viral trigger (measles): Several studies link measles virus (paramyxovirus) persistence in the otic capsule to disease induction; measles RNA detected in otosclerotic foci. The decline of otosclerosis in measles-vaccinated populations supports this link.
3. Hormonal factors: Pregnancy accelerates the disease. Many women first notice hearing loss during or just after their first pregnancy. Estrogen may promote osteoblast activity.
4. Fluoride deficiency: Low fluoride in drinking water correlates with higher disease incidence (basis for sodium fluoride therapy).
5. Autoimmune factors: Some evidence of anti-collagen type II antibodies.

Histopathology

Active Phase ("Otospongiosis")

• Osteoclasts resorb normal lamellar otic capsule bone
• Creates pseudovascular (haversian) spaces filled with marrow-like tissue
• Lesions have affinity for hematoxylin - appear darker than normal bone
• Osteoclasts are multinucleated and found at the advancing edge in finger-like projections
• Early lesions arise adjacent to the fissula ante fenestram (anterior to the oval window)

Inactive/Sclerotic Phase

• Osteoblasts deposit new, disorganized, denser bone
• Lesion enlarges, crosses the stapedial annular ligament
• Causes progressive stapedial fixation

Types of Footplate Fixation

• Anterior fixation (most common) - lesion at fissula ante fenestram
• Bipolar fixation - lesion at both anterior and posterior annular ligament
• "Biscuit footplate" (obliterative otosclerosis) - entire footplate replaced by thick, solid otosclerotic bone; annular ligament totally obliterated

Types / Locations

Clinical Features

Symptoms

• Progressive, bilateral conductive hearing loss - typically insidious onset in 20s-30s
• Hearing is often better in noisy environments (paracusis Willisii - the ability to hear better in noisy surroundings because others raise their voice)
• Tinnitus - low-frequency
• No pain, no discharge (otoscopy is normal)
• Rarely, vertigo (if cochlear otosclerosis or coexisting Meniere's disease)

Signs

• Tympanic membrane: Normal
• Schwartze sign (flamingo pink blush): Reddish blush visible through tympanic membrane over the promontory, due to increased vascularity of active otosclerosis - indicates active disease and favorable prognosis
• Normal external canal

Tuning Fork Tests

Investigations

Pure Tone Audiometry (PTA)

• Low-to-mid frequency air-bone gap (conductive loss)
• Carhart's notch: A characteristic dip in bone conduction at 2000 Hz (mechanical - not true SNHL; it is a mechanical resonance effect of stapes fixation and reverses after stapedectomy)
• Cookie-bite or flat audiogram in advanced cases

Tympanometry

• Type As (shallow) - reduced compliance due to stapes fixation
• Stapedial reflexes absent (stapedius cannot move fixed stapes)

CT Temporal Bone (High-Resolution HRCT)

• Halo sign (double ring sign): Band of demineralization around cochlear capsule in cochlear otosclerosis
• Loss of definition of the oval window margin
• Narrowing or obliteration of the oval window niche
• Evaluates footplate thickness (important pre-operative planning)

Management

1. Hearing Aids

• Always a valid option, especially in elderly patients or those unfit for surgery
• Suitable when air-bone gap is the primary deficit
• Recommended trial before surgery is offered

2. Sodium Fluoride (Medical)

• Dose: 20 mg NaF + calcium/vitamin D daily for 2 years
• Mechanism: Fluoride promotes conversion of hydroxyapatite to fluoroapatite, stabilizing bone remodeling and reducing osteoclast activity
• Indication: Cochlear otosclerosis - to slow or halt SNHL progression
• No effect on established CHL; does not reverse stapes fixation
• Evidence is weak for arresting SNHL; Cummings notes limited definitive proof

3. Surgery - Stapedotomy (Preferred)

1. Four-quadrant canal block with lidocaine + epinephrine
2. Tympanomeatal flap elevated; enter middle ear
3. Remove posterosuperior canal wall overhang (curette/microdrill)
4. Palpate ossicular chain - confirm stapes fixation
5. Measure incus-to-footplate distance (typically 4.5 mm)
6. Laser rosette made in center of footplate
7. Microdrill (0.7 mm diamond bur) creates fenestra in footplate
8. Piston prosthesis placed into fenestra and onto incus
9. Crimp prosthesis hook (or laser for nitinol prostheses)
10. Down-fracture and remove stapes superstructure
11. Tissue graft + blood around prosthesis to seal

• Stapedotomy: Small fenestra (0.6-0.8 mm) in footplate; prosthesis piston through it
• Stapedectomy (total/partial): Removes footplate entirely; covered with tissue graft (vein, fat, perichondrium)
• Stapedotomy is preferred (last 35+ years); stapedectomy reserved for obliterative ("biscuit") footplates where a fenestra cannot be made

4. Cochlear Implantation

• Indicated in bilateral severe-profound mixed or SNHL where stapedotomy cannot restore adequate hearing
• Cochlear otosclerosis causing obliteration of the scala tympani makes implantation technically difficult

Complications of Stapes Surgery

Contraindications to Surgery

• Only hearing ear (relative)
• Active otitis media
• Uncontrolled Meniere's disease
• Perilymph gusher risk (X-linked stapes fixation, widened IAC on CT)
• Bone conduction >45 dB at 500 Hz with high-frequency loss (Cummings)
• Patient unwilling to accept hearing aid as alternative

Differential Diagnosis

• Tympanosclerosis - calcification of middle ear mucosa/ossicles
• Congenital stapes fixation - younger patients, no family history pattern
• Superior semicircular canal dehiscence (SSCD) - third window effect; must exclude
• Fixed malleus head - check full ossicular chain mobility
• Paget's disease of bone - also causes otic capsule remodeling

Recent Evidence

Pathophysiology of Chronic Suppurative Otitis Media (CSOM)

Definition

• Tympanic membrane perforation (central or marginal)
• Recurrent or continuous purulent otorrhea for > 6 weeks (some definitions say > 2 weeks)
• Varying degrees of conductive hearing loss

1. Tubotympanic (safe/benign) CSOM - central perforation, no cholesteatoma
2. Atticoantral (unsafe/dangerous) CSOM - marginal/attic perforation, with cholesteatoma, bone erosion

Step 1 - Predisposing Factors (Setting the Stage)

Eustachian Tube (ET) Dysfunction - The Primary Driver

• The ET normally maintains middle ear pressure, drains secretions into the nasopharynx, and provides mucosal protection
• Dysfunction (obstruction, patulous ET, or impaired mucociliary clearance) causes negative middle ear pressure and impaired drainage
• Results from: adenoid hypertrophy, cleft palate, Down syndrome, craniofacial abnormalities, recurrent upper respiratory infections, poor socioeconomic conditions, and underdeveloped mastoid pneumatization

Mastoid Pneumatization

• Poorly pneumatized mastoid (common in CSOM patients) reduces the air reservoir, worsens negative middle ear pressure, and limits buffering capacity
• Reduced mastoid volume is an almost invariable finding in acquired CSOM with cholesteatoma

Step 2 - Acute to Chronic Transition

From AOM to CSOM

Recurrent AOM / OME
       ↓
Persistent middle ear effusion (serous → purulent)
       ↓
Mucosal edema + inflammatory mediator release
       ↓
TM perforation (acute AOM rupture or chronic retraction)
       ↓
Failure of TM to heal → Chronic perforation
       ↓
CSOM established

Step 3 - Mucosal Pathology in the Middle Ear

Mucosal Metaplasia & Secretory Change

• Normal middle ear mucosa transforms under chronic inflammation into secretory (respiratory-type) mucosa with:
  • Goblet cell hyperplasia
  • Submucosal gland development
  • Ciliated columnar epithelium (normally absent in tympanic cavity)
• This converted mucosa produces mucus, which perpetuates the effusion and creates a substrate for biofilm formation

Inflammatory Cell Infiltration

• Bacterial toxins and inflammatory mediators interact with edematous mucosa
• Basement membrane ruptures - inflammatory cells from the lamina propria enter the middle ear lumen
• Lamina propria extrudes through the disrupted basement membrane

Granulation Tissue Formation

• Chemical mediators trigger:
  • Angiogenic growth factors → neovascularization
  • Epithelial growth factors (EGF) → epithelial proliferation
  • Fibroblast recruitment → fibrous tissue formation
• Combined result: granulation tissue polyps that fill the middle ear and mastoid
• These polyps are friable, bleed easily, and produce enzymes that damage surrounding structures
• Shambaugh Surgery of the Ear, p. 527

Step 4 - Tympanic Membrane Changes

Enzymatic Weakening

• Granulation tissue and chronic effusion contain proteolytic enzymes (collagenase, tPA - tissue plasminogen activator)
• These enzymes degrade the fibrous collagen skeleton of the TM (fibrous middle layer = lamina propria)
• TM loses tensile strength

Retraction Pocket Formation

• ET dysfunction creates chronic negative middle ear pressure
• Combined with enzymatic weakening, the pars flaccida (Shrapnell's membrane - no fibrous layer) and pars tensa retract medially
• Retraction pockets deepen over time
• Contact with underlying mucosa/granulation tissue → fibrous bands anchor the retracted membrane medially
• Eventually → perforation (central in tubotympanic; marginal/attic in atticoantral disease)

Perforation Perpetuation

• Once perforated, the squamous epithelium from the EAC migrates medially over the perforation edge
• This epithelial migration prevents healing and creates a pathway for ongoing contamination from the ear canal

Step 5 - Cholesteatoma Formation (Atticoantral CSOM)

Four Theories of Acquired Cholesteatoma Pathogenesis:

Why Cholesteatoma Causes Bone Destruction

1. Osteoclast activation - the main mechanism
   • IL-1, IL-6, TNF-α, EGF, PGE₂, PTH-rP, TGF-β, OPGL, and M-CSF from cholesteatoma keratinocytes and macrophages activate osteoclasts locally
2. Matrix metalloproteinases (MMPs) and collagenase - directly degrade bone matrix
3. tPA (tissue plasminogen activator) - enables local invasion
4. Pressure necrosis - expansile mass effect compresses and ischemia-necroses surrounding bone
5. Bacterial biofilm LPS - biofilms within chronically infected cholesteatomas elaborate lipopolysaccharide, which amplifies the osteoclast response and contributes to aggressiveness

"The main mechanism of bone resorption in chronic otitis media with and without cholesteatoma is thought to be the increased number and activity of osteoclasts. PGE₂, OPGL, and MCSF are some of the most potent osteoclast-activating metabolites. Cytokines and growth factors such as IL-1, IL-6, TNFα, EGF, PTH-rP, and TGFβ seem to play an important role in middle ear infections and cholesteatoma." - Cummings Otolaryngology, p. 2697

Step 6 - Microbiology & Biofilm Role

Organisms

• Pseudomonas aeruginosa - most common (especially in persistent/resistant CSOM)
• Staphylococcus aureus - including MRSA
• Proteus mirabilis
• Klebsiella pneumoniae
• Anaerobes (Bacteroides, Peptostreptococcus) - in atticoantral disease
• Fungi (Candida, Aspergillus) - especially after prolonged topical antibiotics

Biofilm Formation

• Bacteria in CSOM form biofilms - structured communities encased in an extracellular polysaccharide matrix adhered to mucosal surfaces
• Biofilm bacteria are 100-1000x more resistant to antibiotics than planktonic (free-floating) bacteria
• Explain chronic, treatment-refractory nature of CSOM
• Biofilms in cholesteatoma elaborate LPS which further activates osteoclasts

Step 7 - Ossicular Erosion & Hearing Loss

Ossicular Involvement (in order of frequency)

1. Long process of incus - most commonly eroded (watershed zone, tenuous blood supply)
2. Stapes suprastructure
3. Malleus handle

Mechanism of Erosion

• Enzymatic (collagenase, MMPs) from granulation tissue/cholesteatoma
• Osteoclast-mediated bone resorption
• Pressure necrosis from expanding cholesteatoma mass

Hearing Loss

• Conductive (CHL) - from TM perforation + ossicular erosion (CHL > 30 dB suggests ossicular involvement)
• Sensorineural (SNHL) - from:
  • Toxin/enzyme spread through the round window membrane to the inner ear
  • Labyrinthitis (serious complication)
  • Fistula of the lateral semicircular canal
• Note: SNHL of 5-33 dB is found in many CSOM patients and should be documented preoperatively

Summary: Pathophysiological Cascade

ET Dysfunction + Poor Mastoid Pneumatization
          ↓
Negative Middle Ear Pressure → Persistent Effusion
          ↓
Mucosal Edema → Bacterial Infection → Purulent Effusion
          ↓
Mucosal Metaplasia (secretory) → Granulation Tissue Formation
          ↓
Enzymatic Weakening of TM → Retraction Pockets → Perforation
          ↓
  TUBOTYMPANIC CSOM              ATTICOANTRAL CSOM
  (Central perforation)         (Marginal/attic perforation)
  Granulation tissue             ↓
  Mucosal thickening         CHOLESTEATOMA FORMATION
  Ossicular erosion               ↓
  (enzymatic/granulation)    Osteoclast activation
                             (IL-1, IL-6, TNF-α, PGE₂)
                             + Biofilm amplification
                                  ↓
                         Bone erosion → Complications

Complications (by Extension of Pathophysiology)