title: Computed tomography-based workup of conductive hearing loss with normal middle ear: don't forget superior semicircular canal dehiscence.
abstract: Patients with superior semicircular canal dehiscence (SSCD) may have conductive hearing loss (CHL) with normal middle ear (ME). A patient with CHL and normal tympanic membrane at otoscopy underwent tympanotomy for presumed otosclerosis but had negative intraoperative findings. A high-resolution computed tomography (CT) scan of the temporal bone performed a few years later showed the absence of middle-ear disorder (especially the absence of imaging signs of otosclerosis) and revealed a bony dehiscence of the superior semicircular canal. High-resolution CT scan is the test of choice for diagnosing SSCD; it mimics otosclerosis by manifesting itself as CHL with a normal ME. The aim of this study is to remind radiologists and otolaryngologists that SSCD should be systematically considered among the etiologies of CHL with normal ME.
authors.affiliation: Otology-Neurootology Unit, Fondation Adolphe de Rothschild, Paris, France.
authors.forename: Christian B
authors.initials: CB
authors.lastname: Teszler
authors.forename: Mary
authors.initials: M
authors.lastname: Daval
authors.forename: Khaled
authors.initials: K
authors.lastname: Altabaa
authors.forename: Marc T
authors.initials: MT
authors.lastname: Williams
authors.forename: Denis
authors.initials: D
authors.lastname: Ayache
mesh_terms: D001309:Auditory Threshold; D003937:Diagnosis, Differential; D004432:Ear, Middle / Q000000981:diagnostic imaging*; D006314:Hearing Loss, Conductive / Q000000981:diagnostic imaging* / Q000209:etiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007759:Labyrinth Diseases / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D010040:Otosclerosis / Q000000981:diagnostic imaging*; D012665:Semicircular Canals / Q000000981:diagnostic imaging*; D013701:Temporal Bone / Q000000981:diagnostic imaging; D036542:Tomography, Spiral Computed