Classification of endolymphatic hydrops.

Ménière's disease is but one member of a family of disorders linked by the common pathophysiologic substrate of endolymphatic hydrops. The authors evaluated both clinical cases and temporal bone specimens and conclude that endolymphatic hydrops is a pathologic condition that is the final common manifestation of a variety of otologic insults. They present a logical classification which, on the basis of clinical data, distinguishes symptomatic and asymptomatic forms. The hallmarks of the symptomatic form are fluctuating hearing loss and episodic vertigo. The asymptomatic form is clinically silent. Each form may be further subclassified into embryopathic, acquired, and idiopathic types. The embryopathic type comprises those cases in which a noxious influence disrupts labyrinthine development in utero. The acquired type includes those cases in which a documented insult, either inflammatory or traumatic, is suffered by a previously normal labyrinth. The idiopathic type encompasses all those cases in which the event precipitating the endolymphatic hydrops is unknown. Ménière's disease is redefined as idiopathic, symptomatic endolymphatic hydrops.