Effects of Intratympanic Injection of Isosorbide on the Vestibular Function of Animal Models of Endolymphatic Hydrops.
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ABSTRACT: Objectives
The aims of this study were to investigate the effects of intratympanic injections of isosorbide on vestibular function in animal models of endolymphatic hydrops and to find a new treatment option for the acute onset of vertigo in Ménière disease (MD).Methods
Seventy male guinea pigs received intratympanic injection of isosorbide (IT-ISB). The animals were divided into three study groups: control, a chronic hydrops model, and an acute hydrops model. Intracochlear drug concentrations were measured using high-performance liquid chromatography. Vestibular function was analyzed using an animal rotator test with bidirectional sinusoidal harmonic acceleration before and after IT-ISB administration. Histological changes were also investigated.Results
ISB successfully permeated the perilymph through the round window membrane (RWM) at all three concentrations (25%, 50%, and 100%). In the chronic hydrops model, while IT-ISB histologically induced a reduction of endolymphatic hydrops, vestibular function was unchanged. In the acute hydrops model, no endolymphatic hydrops was histologically observed, and vestibular symmetry was also preserved after IT-ISB.Conclusion
ISB passed through the RWM into the perilymphatic space even at lower concentrations. IT-ISB histologically reduced hydrops in the chronic model and preserved symmetrical vestibular function in the acute model. IT-ISB could be a treatment candidate for acute attacks of vertigo in MD.
SUBMITTER: Kim M
PROVIDER: S-EPMC8606285 | biostudies-literature |
REPOSITORIES: biostudies-literature
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