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MENIERE'S DISEASE
DEFINITION
? Disorder of inner ear where endolymphatic system is distended with endolymph
? Other name : endolymphatic hydrops
? Characterised by
1.
Vertigo
2.
Tinnitus
3.
Sensorineural hearing loss
4.
Aural fullness
PATHOLOGY
? Distension of the endolymphatic system
? Affects
1. Cochlear ducts
2. Saccule
3. Utricle
4. Semicircular canals
The dilatation of cochlear duct is such that it may completely fil
the scala vestibuli and there is marked bulging of reissners
membrane,which may herniate through the helicotrema into
apical part of scala tympani
AETIOLOGY
? Either due to increased production (stria
vascularis) of endolymph or faulty
absorption(endolymphatic sac)
THEORY
? Defective absorption by endolymphatic sac
? Vasomotor disturbance
? Al ergy
? Sodium and water retention(excess fluid retained)
? Hypothyroidism
? Autoimmune and viral aetiology
DEFECTIVE ABSORPTIONS BY ENDOLYMPHATIC SAC
? Normal y endolymphatic sac to endolymphatic duct
? Experimental obstruction of endolymphatic sac and its duct
produce hydrops
? Distension of membranous labyrinth leads to rupture of
reissner's membrane and thus mixing of perilymph and
endolymph which brings vertigo
VASOMOTOR DISTURBANCE
? Sympathetic overactivity resulting in spasm of internal auditory
artery /its branches thus interfering the function of cochlear or
vestibular sensorineural epithelium
? Anoxia of capil aries of stria vascularis also causes increased
permeability with transudation of fluid and increased
production of endolymph
ALLERGY
? In cases of offending al ergen , inner ear acts as a shock organ
producing excess endolymph
? 50 percent patients with Meniers disease hav concomitant
inhalant/food al ergy
THANK YOU
This post was last modified on 12 August 2021