INTRODUCTION: This study aims to compare the stria vascularis and spiral ligament, and evaluate the bony arch around the vestibular aqueduct, in temporal bones with endolymphatic hydrops (EH) from patients with (EH+), and without (EH-) vestibular symptoms, compared to control temporal bones, to better understand the mechanism of vestibular symptoms in Meniere disease.
METHODS: A total of 30 temporal bones (twelve EH+, six EH-, and twelve controls from 27 subjects [mean age 72 years; range 61-89 years]) were retrospectively evaluated in this study. Exclusions were ototoxicity, systemic or neurologic diseases. Stria vascularis areas were measured in all cochlear turns. The spiral ligament was divided into four sections according to fibrocytes. The bony area around the vestibular aqueduct was evaluated according to cellular appearance.
RESULTS: Stria vascularis area between EH+ and EH- in any turn except upper middle was statistically insignificant. Loss of fibrocytes was not statistically different between any groups. Denuded osteoblasts, and diminished edges around bony layer of vestibular aquaduct were statistically different in EH+ and EH- (p=.0003).
DISCUSSION AND CONCLUSION: Lack of histopathologic differences in cochlear lateral walls between any group suggest that these changes might not be responsible for generation of vestibular symptoms. Significant degenerative changes in the vestibular aqueduct in EH+ compared to EH- bones may suggest a relationship of the vestibular aqueduct and vestibular symptoms.