Endolymphatic hydrops is prevalent in the first weeks following cochlear implantation

Abstract

Aim: To explore morphological or electrophysiological evidence for the presence of endolymphatic hydrops (EH) in guinea pig cochleae in the first 3 months after cochlear implantation. Methods: Dummy silastic electrodes were implanted atraumatically into the basal turn of scala tympani via a cochleostomy. Round window electrocochleography (ECochG) was undertaken prior to and after implantation. Animals survived for 1, 7, 28 or 72 days prior to a terminal experiment, when ECochG was repeated. The cochleae were imaged using micro-CT after post-fixing with osmium tetroxide to reveal the inner ear soft tissue structure. EH was assessed by visual inspection at a series of frequency specific places..