Surdités brusques : intérêt de l’imagerie

Abstract

Review the CT and MR imaging findings in patients with sudden deafness (SD). Thirty-seven patients with SD were prospectively included. All patients underwent MR evaluation of the brain and temporal bones to exclude classical etiologies such as vestibular schwannoma. CT of the temporal bones was also performed to exclude lesions of the bony labyrinth. A total of 100 CT examinations of the temporal bone in control subjects were reviewed and measurements obtained to establish a reference standard to compare to findings in our patient population. Findings included: vestibular schwannoma in 2.7%, labyrinthine hemorrhage in 8.1%, bony labyrinthine anomaly in 59.5% according to our criteria, and significantly more frequent than in our control subjects, including dehiscence of the superior semicircular canal in 8.1%, lateral semicircunal canal anomaly in 27% and vestibular anomaly in 16.2%. Some of the classical etiologies of SD were detected in our patient population, along with a high prevalence of size or morphological anomalies of the bony labyrinth, diagnosed in most cases from systematic measurements from CT images. In time, MRI should also allow detection of these abnormalities and diagnosis of lesions currently not detectable on MRI.