The basic science of Meniere's disease and endolymphatic hydrops.
OBJECTIVE
Meniere's disease is characterized by the triad of fluctuating hearing loss, episodic vertigo, and tinnitus and by endolymphatic hydrops found on post-mortem examination. The cause of Meniere's disease remains unclear. Numerous factors play a role in the development of hydrops and in the pathogenesis of related cochleovestibular dysfunction. This review highlights recent advances in the understanding of the pathophysiology of symptom development in Meniere's disease by detailing the role of genetics, autoimmunity, endolymphatic fluid homeostasis, excitotoxicity, oxidative stress, and cellular apoptosis. Emphasis is placed on reviewing the newly described animal models that exhibit endolymphatic hydrops.


RESULTS
Recent evidence suggests that hearing loss might be explained in part by apoptosis of spiral ganglion neurons and that hydrops could represent an epiphenomenon rather than an initiating factor. In addition, the accepted guinea pig model described by Kimura has certain limitations. An animal model that would supplement and in some cases replace the surgically induced model is currently being sought.


CONCLUSIONS
These recent advances have expanded our understanding and will allow for the development of targeted therapeutic interventions aimed at preventing the progression oochleovestibular deterioration.
Semaan
Maroun T
MT
Department of Otolaryngology-Head and Neck Surgery, University Hospitals of Cleveland, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA.
Alagramam
Kumar N
KN
Megerian
Cliff A
CA
D000818:Animals; D004195:Disease Models, Animal; D018159:Endolymphatic Hydrops / Q000503:physiopathology*; D006801:Humans; D008575:Meniere Disease / Q000503:physiopathology*; D051379:Mice