Significance of Endolymphatic Hydrops in Ears With Unilateral Sensorineural Hearing Loss

The purpose of this study was to investigate the existence of endolymphatic hydrops (EH) in affected and unaffected ears in patients with unilateral sensorineural hearing loss (SNHL) using contrast-enhanced magnetic resonance imaging (MRI), and to evaluate the significance of EH in various otological diseases.

Retrospective study.

University hospital.

One hundred eighty-two ears from 91 patients with unilateral SNHL were studied. The endolymphatic space was evaluated using 3-Tesla MRI with gadodiamide hydrate. Imaging data about the degree of EH in the cochlea and vestibule were analyzed and compared between ears with various otological diseases.

All affected ears with delayed endolymphatic hydrops had EH. In affected ears with definite Menière's disease, cochlear EH was observed in all ears and vestibular EH in 93% of ears, and these rates were significantly higher in the affected than in the unaffected ears. EH was also observed in the cochlea and vestibule in 66% and 41%, respectively, of the affected ears with idiopathic sudden SNHL; however, these percentages did not differ significantly from those in the unaffected ears (52% and 38%, respectively).

MRI showed that a high percentage of ears affected by Menière's disease or delayed endolymphatic hydrops had EH. Further studies should evaluate the implications of EH in ears, especially in those with sudden SNHL, in terms of secondary or pre-existing EH.