Sensorineural hearing loss due to cochlear otospongiosis: theoretical considerations of etiology.

Several theories have been advanced to explain the sensorineural hearing loss that occurs in patients with otospongiosis: toxic substances produced by the otospongiotic focus; vascular shunts betwen the inner ear vessels and the otospongiotic focus; and atrophy of the organ of Corti and stria vascularis due to unknown causes. Presented here is yet another theory: impingement upon the cochlear walls by the otospongiotic focus, causing a narrowing of the lumen of the cochlea and distortion of the basilar membrane.