Vestibular atelectasis.

The temporal bone collection at the Massachusetts Eye and Ear Infirmary includes specimens from several cases in which the only reasonable explanation for vertigo is collapse of the walls of the ampullae and utricle, a disorder we have termed vestibular atelectasis. The clinical histories and temporal bone studies support the existence of a primary type that may have a paroxysmal or insidious onset, and a secondary type that occurs in association with other inner ear disorders. The principal clinical symptom is chronic unsteadiness, precipitated or aggravated by head movement, and sometimes associated with short episodes of spinning vertigo. It is presumed that the collapsed membranes interfere with the motion mechanics of the cupulae and otolithic membranes.