title: Modeled Analysis of Entrance of Colloid Suspensions into the Middle Ear Cavity.
abstract: Otic suspensions have a positive effect on the duration of otorrhea in children with a tympanostomy tube. It is still questionable how eardrops reach the middle ear. We hypothesized that otic suspensions do not pass the tympanostomy tube if the middle ear is dry but pass by diffusion when wet. The median concentration of Evans blue (colorant) in the middle ear was <15.6 mg/mL (lower limit of quantification) when diffusion was impossible but 45.3 µg/mL when diffusion was possible (P = .01). When the outward flow was increased to 0.1 mL/h, the concentration of Evans blue in the middle ear increased significantly (P = .03). With further-increasing outward flows, the concentration of Evans blue decreased linearly (β = -144, P < .001, R (2) = 0.44). We conclude that diffusion is the mechanism by which otic suspensions enter the middle ear in children with tympanostomy tubes and otorrhea.
authors.affiliation: Medical Faculty, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Bahar
authors.initials: B
authors.lastname: Ariana
authors.affiliation: Department of Otorhinolaryngology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Simon
authors.initials: S
authors.lastname: Geerse
authors.affiliation: Department of Otorhinolaryngology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Linda J
authors.initials: LJ
authors.lastname: Schot
authors.affiliation: Medical Faculty, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands Laboratory of Experimental Intensive Care and Anesthesiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands l.d.bos@amc.uva.nl.
authors.forename: Lieuwe D J
authors.initials: LD
authors.lastname: Bos
mesh_terms: D003102:Colloids / Q000493:pharmacokinetics*; D004396:Coloring Agents / Q000493:pharmacokinetics*; D004432:Ear, Middle / Q000473:pathology*; D005070:Evans Blue / Q000493:pharmacokinetics*; D006801:Humans; D066298:In Vitro Techniques; D008876:Middle Ear Ventilation; D013535:Suspensions / Q000493:pharmacokinetics*
chemical_list: D003102:Colloids; D004396:Coloring Agents; D013535:Suspensions; D005070:Evans Blue
keywords: diffusion; otic suspensions; otorrhea; tympanostomy tubes