Magnetic Resonance Imaging Evaluation of Endolymphatic Hydrops in Cases With Otosclerosis

OBJECTIVE: Endolymphatic hydrops (EH) has been reported in cases with otosclerosis, and preoperative EH could be a risk factor for inner ear disturbances after stapes surgery. Visualization of EH has recently become possible using magnetic resonance imaging (MRI) with contrast agents. This study investigated the presence of EH on MRI in ears with clinical otosclerosis. STUDY DESIGN: Retrospective case series. SETTING: University hospital. PATIENTS: 27 ears of 15 cases diagnosed with otosclerosis. INTERVENTION: Ears were evaluated by 3-T MRI performed 4 hours after intravenous injection of gadolinium. The degree of EH in the vestibule and cochlea was classified into three grades (none, mild, and significant). Imaging data were compared with clinical findings for all ears. MAIN OUTCOME MEASURES: Imaging and clinical findings. RESULTS: Varying degrees of cochlear EH and vestibular EH were observed in 20 and 15 ears, respectively. Episodes of acute sensorineural hearing loss with rotatory vertigo occurred in four ears that showed severe EH in the cochleae and vestibules. Severe EH, however, was also observed in ears without such symptoms. CONCLUSIONS: The presence of EH in ears with otosclerosis was clearly visualized in the present patient series. Such MRI evaluation could provide useful information for managing symptoms related to EH.