Saccular Otoconia as a Cause of Ménière Disease

Abstract

Objective: Idiopathic endolymphatic hydrops can be caused by disturbance of the longitudinal flow of the endolymph in Ménière disease. This study investigated a possibility that the dislodged otoconia from the saccule could be a cause of Ménière disease by occluding the pathway of the endolymph.

Method: We examined the ears of 65 patients with definitely diagnosed unilateral Ménière disease based on the criteria proposed by the AAO-HNS and the ears of normal control subjects and cadavers using three-dimensional (3D) cone beam CT by focusing on the vestibule.

Results: The images of the reuniting duct and the saccular duct could be categorized by their patency. In the case of Ménière ears, both the reuniting duct and the saccular duct were occluded significantly compared with those of normal ears. The ears of the nonlesional side of Ménière patients also showed the occluded aspects of these ducts. The endolympatic sinus, which connects to the saccular duct, suggested relations with Ménière attack.

Conclusion: Patients with Ménière disease often show a significantly higher incidence of blockage of the reuniting duct and saccular duct. There is a big probability that radiodense substances such as saccular otoconia falling into these ducts may be one of the etiologies of Ménière disease.