Minimally invasive trans-tympanic eustachian tube occlusion animal model

Abstract

ObjectiveEustachian tube dysfunction is believed to be involved in the pathogenesis of many middle ear diseases including chronic suppurative otitis media. We aimed to describe a simple and reliable animal model of Eustachian Tube obstruction to further research into middle ear disorders. Study designProspective cohort study in animals. SettingUniversity laboratory. Subjects and methods30 mice C57Bl/6J (n = 15) and CBA/CaJ (n = 15) aged 6–8 weeks received transtympanic Eustachian tube occlusion on left ear trough an acute tympanic membrane perforation using thermoplastic latex used in dental procedures (gutta percha). Control mice (n = 6) received tympanic membrane perforation only. At two and four weeks, the mice were observed for signs of Eustachian tube dysfunction and compared to control ears. ET dysfunction was defined as presence of effusion in the middle ear. Results100% (n = 30) of the treated ears had otoscopic signs of Eustachian tube dysfunction at two weeks and the endpoint time of four weeks, compared to 0% in control mice (0/6). Temporary head tilt lasting up to 2 days were observed in 3 mice (10%). No other potential adverse events were recorded. No bacterial growth was determined in the middle ear fluid. ConclusionWe describe a technically easy and reliable method for Eustachian tube occlusion in mice with an excellent success rate and minimal morbidity.