This explains the pathophysiology, histology and the diagnostic criteria of Meniere's disease

1. MÉNIÈRE’S DISEASE
PATHOPHYSIOLOGY AND
CLINICAL FEATURES
Dr Prajwal Dange

2. INTRODUCTION
• Ménière’s disease is an idiopathic inner ear disorder characterized by
recurrent spontaneous vertigo accompanied by fluctuating or progressive
sensorineural hearing loss, tinnitus and aural fullness in the affected ear.
• The vertigo episodes - most incapacitating.
• Ménière’s disease is, by definition, the idiopathic type of endolymphatic
hydrops.
• Ménière’s syndrome is secondary type presenting a similar clustering of
symptoms caused by, for example, syphilis, trauma, autoimmune
disorders.

3. HISTORY
• Prosper Meniere first described the symptom complex of the
eponymous disease in 1861.
• Proposed the pathologic site to be in the labyrinth.
• Knapp advanced the hypothesis that hydrops was similar to ocular
glaucoma.
• Histologically demonstrated in 1938.

4. INCIDENCE
• 4.3 per 100 000 population per
year.
• More prevalent among whites
• Equal gender distribution.
• Age of onset - second to sixth
decade.
SPORADIC
• Majority of cases are sporadic.
FAMILIAL
• Estimated 5–15% of cases are
familial.
• Various genes are proposed which
includes AQP2, KCNE1, KCNE3,
HCFC1, COCH, ADD, HSPA1A,
PTPTN22 and IL1.

7. • The endolymphatic sac can be divided into 3 portions based on the
cellular lining:
(1) the proximal (rugose) portion, in vestibular aqueduct and is
constituted by the same epithelia of the endolymphatic duct
(2) the intermediate portion, partly inside of the vestibular aqueduct
and partly between layers of dura, which consists of cuboidal cells
(3) the distal portion, which lies within layers of dura mater and is lined
by cuboidal cells.

8. PRODUCTION AND REGULATION OF ENDOLYMPH
• Endolymph is not only potassium-rich (150-180 mmol/L) but also
nearly sodium-free.
• Evidence points toward the formation of endolymph from perilymph,
rather than from plasma.
• The transepithelial K+ transportation from perilymph to endolymph
through the Na+,K+ ATPase ion pump is responsible for maintaining
both the high endocochlear electric potential and the unique
composition of endolymph.

9. • The stria vascularis is responsible for the secretion of endolymph,
with small contributions from the planum semilunatum and from
dark vestibular cells.
• The rate of endolymph secretion seems to be influenced by a number
of factors and hormones, including aldosterone and vasopressin.

10. • Endolymph flows within the membranous labyrinth, by 2 concurrent
mechanisms:
• (1) radial (a rapid, ongoing process), which is important for energy
metabolism and ion exchange around the sensory cell regions; and
• (2) longitudinal (slow) flow, which enables reabsorption of endolymph
and disposal of high-molecular waste products and debris by the
endolymphatic sac.
• Those 2 mechanisms occur simultaneously, in a continuous fashion.

11. PATHOPHYSIOLOGY
ENDOLYMPHATIC HYDROPS
• Obstruction of the endolymphatic duct is the basis for development
of hydrops in experimental animals.
• Lesion producing failure of duct function by mechanical blockage,
chemical fibrosis, viral inoculation, immunologically induced
inflammation, and ischemia
• This theory remains controversial although it was observed in all
temporal bones with Ménière’s disease.

12. • Clinical data supporting this theory is based on delayed MRI after
intratympanic or intravenous administration of gadolinium-based
contrast agents.
• In electrocochleography, large summating potential has been
observed in 50–70% of patients with Ménière’s disease, which can be
reduced with administration of hyperosmotic substances.

13. • Endolymphatic hydrops is not pathognomonic to Ménière’s disease.
• Endolymphatic hydrops was observed in a significant number of
temporal bones from patients with hearing loss, without the classical
symptoms of Ménière’s disease.
• Delayed MRI after intratympanic injection of gadolinium-based
contrast agent in unilateral Ménière’s disease reveals bilateral
endolymphatic hydrops quite frequently.

14. • Schuknecht postulated
Ruptures in the membranous labyrinth
Leakage of the potassium rich endolymph into the perilymph
bathes the eighth cranial nerve and lateral sides of the hair cells

15. High concentrations of K+
Depolarize the nerve cells
Acute inactivation
Decrease in auditory and vestibular neuronal outflow

16. Healing of the membranes
Restitution of the normal chemical balance
Termination of the attack
Improvement in vestibular and auditory function
• Healed scars, have also been identified which supports this theory.

17. AUTOIMMUNE FACTOR
• In approximately 1 in 3 patients seems to have an autoimmune factor.
• Several theories were suggested, including
• cross-reactions between similar antigens,
• innocent bystander damage due to cytokine release,
• acquired intolerance to inner ear antigens (covert from the immunological
system and exposed by trauma or infection)

18. VASCULAR FACTOR
• It has been observed that endolymphatic hydrops impairs blood flow
autoregulation.
• The combination of endolymphatic hydrops and venous obstruction
has shown to induce vertigo attacks similar to Ménière’s disease in an
animal model.

19. VIRAL FACTOR
• A viral etiology has been suggested as well, most often involving the
herpes simplex virus.
• Viral structures have been observed by means of transmission
electron microscopy in the vestibular ganglion cells of Ménière’s
disease patient, which supports this theory.
ALLERGIC FACTOR

21. HISTOPATHOLOGY
• Hallpike, Cairns and Yamakawa report considered hallmarks of the
disease (dilation of the scala media of the cochlea, with displacement
of Reissners membrane into the vestibular scala).

26. CLINICAL PRESENTATION
• No single test makes the diagnosis of Meniere disease.
Clinical presentation
• The typical history consists of
• Recurring attacks of vertigo (96.2%) with
• Tinnitus (91.1%) and
• Sensory neural hearing loss (87.7%).

27. VERTIGO
• Attacks are often preceded by an aura that consists of a sense of
fullness in the ear, increasing tinnitus, and a decrease in hearing.
• However, onset may be sudden with little or no warning.
• The classic presentation is not always detailed by the patient.

28. • A typical attack of Ménière’s disease can be defined by the direction
of the spontaneous nystagmus.
• Irritative phase - The nystagmus will beat towards the affected ear in
a horizontal or horizontal–torsional direction, a finding which usually
lasts less than 1 hour.
• Paretic phase - The nystagmus will beat away from the affected
ear and last hours to days.
• Recovery phase - The nystagmus again beats towards the affected
side because peripheral vestibular function recovers.

29. • The clinical course is highly variable.
• Long remissions.
• Silverstein and colleagues found that vertigo ceased spontaneously in
57% of patients in 2 years and in 71% after 8.3 years.

30. • Sudden unexplained falls without loss of consciousness or associated
vertigo are occasionally described.
• Tumarkin attributed these to acute utriculosaccular dysfunction, so-
called otolithic crises of Tumarkin or drop attacks.
• It is thought that an erroneous vertical gravity reference occurs as a
consequence of an abrupt change in otolithic input.
• This in turn generates an inappropriate postural adjustment via the
vestibulospinal pathway, which results in a sudden fall.

31. • Attacks are so sudden that injury can occur, and the patient often
describes being pushed or feeling the world moving.
• The spells are short lived with little associated vertigo.
• Drop attacks have been reported in 2% to 6% of people with Meniere
disease, and they tend to occur in clusters and then spontaneously
remit.

33. • Lermoyez described an unusual clinical presentation in which tinnitus
and hearing loss precede and worsen with the onset of vertigo: when
the vertiginous episode occurs, the tinnitus and hearing loss
dramatically resolve.
• The temporal bone studies of one individual with such attacks noted
hydrops and membrane ruptures isolated to the basal turns of the
cochlea and the saccule.

36. HEARING LOSS
• Low-frequency sensorineural hearing loss is defined as increases in
pure-tone thresholds for bone-conducted sound that are higher
(i.e. worse) in the affected ear than the contralateral ear by at least
30 dBHL at each of two contiguous frequencies below 2 kHz.
• In cases of bilateral low-frequency sensorineural hearing loss, the
absolute thresholds for bone-conducted sound must be 35 dBHL or
higher at each of two contiguous frequencies below 2000 Hz.

37. • If multiple audiograms are available, demonstration of recovery of
low-frequency sensorineural hearing loss at some point in time
further supports the diagnosis of Ménière’s disease. Bilateral
synchronous sensorineural hearing loss (symmetric or asymmetric)
can occur in some patients.

39. • Additional features include diplacusis, a difference in the perception
of pitch between the ears (43.6%), and recruitment (56%).
• Tinnitus tends to be non pulsatile and is variously described as
whistling or roaring.
• It may be continuous or intermittent.
• Tinnitus often begins, gets louder, or changes pitch as an attack
approaches; after the attack, a period of improvement is common.

42. CRITERIA FOR DIAGNOSIS
• Vertigo
• Recurrent, well-defined episodes of
spinning or rotation
• Duration from 20 minutes to 24 hours
• Nystagmus associated with attacks
• Nausea and vomiting during vertigo
spells (common)
• No neurologic symptoms with vertigo
• Deafness
• Fluctuating hearing deficits
• Sensorineural hearing loss
• Progressive hearing loss, usually
unilateral
• Tinnitus
• Variable, often low pitched and louder
during attacks
• Usually unilateral
• Subjective

43. DIAGNOSIS OF MENIERE DISEASE
• Possible Meniere Disease
• Episodic vertigo without hearing loss or
• Sensorineural hearing loss, fluctuating or fixed, with dysequilibrium but
without definite episodes
• Other causes excluded
• Probable Meniere Disease
• One definitive episode of vertigo
• Hearing loss documented by audiogram at least once
• Tinnitus or aural fullness in the suspected ear
• Other causes excluded

44. • Definite Meniere Disease
• Two or more definitive spontaneous episodes of vertigo lasting at least 20
minutes
• Audiometrically documented hearing loss on at least one occasion
• Tinnitus or aural fullness in the suspected ear
• Other causes excluded
• Certain Meniere Disease
• Definite Meniere disease plus histopathologic confirmation

45. • The most recent guidelines for the diagnosis in patients with
Ménière’s disease were issued in 2015.