title: A safety evaluation of dexamethasone-releasing cochlear implants: comparative study on the risk of otogenic meningitis after implantation.
abstract: CONCLUSIONS
  Dexamethasone released from a cochlear implant seems not to enhance the risk for postoperative infections.
  
  
  OBJECTIVE
  Dexamethasone has a positive impact on hearing preservation for electric acoustic stimulation (EAS). Due to their antiproliferative and immunosuppressive properties, steroids may enhance the risk of postoperative infections. A comparative study was performed to evaluate the risk of pneumococcal meningitis after implantation of dexamethasone-eluting cochlear implants.
  
  
  METHODS
  Thirty guinea pigs were implanted with non-eluting (n = 15) or dexamethasone-eluting (n = 15) cochlear implant electrode dummies. After 5 weeks, animals were exposed to a virulent strain of Streptococcus pneumoniae. The two groups were compared based on the meningitis rate. Animals were observed for 5 days for signs of meningitis. Meningitis was verified by clinical outcome as well as by pleocytosis and presence of bacteria in cerebrospinal fluid. Results were confirmed by histological examination of brains and cochleae, clinical findings and culture.
  
  
  RESULTS
  There was no significant difference in meningitis risk between the two groups. In the group with non-eluting implants, 3 of 15 animals developed meningitis, while in the group with dexamethasone-eluting implants 4 of 15 showed signs of meningitis. In this study dexamethasone-releasing implants did not significantly increase the risk of postoperative pneumococcal otogenic meningitis.
authors.affiliation: Clinic for Otorhinolaryngology, Head- and Neck Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Niedermeier
authors.forename: Susanne
authors.initials: S
authors.lastname: Braun
authors.forename: Claudius
authors.initials: C
authors.lastname: Fauser
authors.forename: Jan
authors.initials: J
authors.lastname: Kiefer
authors.forename: Reinhard K
authors.initials: RK
authors.lastname: Straubinger
authors.forename: Thomas
authors.initials: T
authors.lastname: Stark
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000009:adverse effects*; D054316:Biomarkers, Pharmacological / Q000032:analysis; D003054:Cochlear Implants; D003907:Dexamethasone / Q000008:administration & dosage* / Q000009:adverse effects; D004567:Electrodes, Implanted; D006168:Guinea Pigs; D008586:Meningitis, Pneumococcal / Q000473:pathology / Q000517:prevention & control*; D011474:Prosthesis Design; D016459:Prosthesis-Related Infections / Q000473:pathology / Q000517:prevention & control*; D012533:Scala Tympani / Q000473:pathology; D054738:Scala Vestibuli / Q000473:pathology
chemical_list: D000893:Anti-Inflammatory Agents; D054316:Biomarkers, Pharmacological; D003907:Dexamethasone