DRGANOF.CORTIMeniere'’ s Disease
Meniere’s Disease
DefinitionMeniere's Disease,alsocalled endolymphatichydrops,is a disorder oftheinnerearwheretheendolymphaticsystemisdistendedwithendolymph.It is characterized by(i) vertigo,(ii)sensorineural hearingloss,(ii)tinnitus,(iv) aural fullness
Definition Meniere' s Disease, also called endolymphatic hydrops, is a disorder of the inner ear where the endolymphatic system is distended with endolymph . It is characterized by (i) vertigo , (ii) sensorineural hearing loss， (iii) tinnitus ， (iv) aural fullness
BackgroundIn 1861,oProsperMenieredescribedasyndromeIn1938oHallpikeandYamakawareportedthefindingofendolymphatichydropsintemporalbonefrompatientswithMDCross.section.of.cochleaScataTectorialmediamembraneScalaVestibuliSpiralganglion.ScalatympaniInnerOuterhaircllshaircellsBasilarmembrano
Background In 1861, ◦ Prosper Meniere described a syndrome In 1938, ◦ Hallpike and Yamakawa reported the finding of endolymphatic hydropsin temporal bone from patients with MD
PrevalenceEpidemiology4/100000inJapan.15/100000inUS,-46/100000inSweden,100/100000inUKThelargedifferencesaredueto- Geographic, genetic, ethnic or environmental factors,or different diagnostic criteria
Prevalence Epidemiology – 4/100000 in Japan. – 15/100000 in US, – 46/100000 in Sweden, – 100/100000 in UK. The large differences are due to – Geographic, genetic, ethnic or environmental factors, or different diagnostic criteria
PathologyEndolymphatichydropsThehydropsprincipallyinvolvesthecochlearductandsacculebutwerenotobviousintheutricleandampullaeofsemicirclarcanals.Decreaseintheamountoflooseconnectivetissuearoundtheendolymphaticsachypoplasiaofvestibularaqueduct,anddecreasedsacand perisaccularfibrosiswerealsoobserved
Pathology Endolymphatic hydrops ◦ The hydrops principally involves the cochlear duct and saccule but were not obvious in the utricle and ampullae of semicirclar canals. Decrease in the amount of loose connective tissue around the endolymphatic sac, hypoplasia of vestibular aqueduct, and decreased vascularization of the sac and perisaccular fibrosis were also observed