title: Effects of systemic administration of methylprednisolone on residual hearing in an animal model of cochlear implantation.
abstract: CONCLUSIONS
  Delivery of intramuscular injection of methylprednisolone around the implantation surgery improved the hearing threshold shift induced by cochlear implantation.
  
  
  OBJECTIVE
  During electroacoustic cochlear implantation surgery, the residual hearing is not preserved in about 15% of cases. In this study, we tested the effects of intramuscular administration of methylprednisolone on the hearing loss induced by cochlear implantation in a model of guinea pig cochlear implantation.
  
  
  METHODS
  Eleven guinea pigs with normal hearing were implanted with a 254 μm diameter silicone array through a cochleostomy, and the effects on hearing of longstanding array insertion (21 days) were assessed. Six of the implanted animals received intramuscular administration of methylprednisolone. Auditory brainstem response recordings were performed before and up to 21 days after the cochlear implantation. CT scans were performed in some animals 1 month after implantation.
  
  
  RESULTS
  CT scans confirmed that the array was well positioned in tested animals. From days 3 to 21, a hearing loss of about 30 dB on all frequencies was observed in the implanted nontreated group. This hearing loss remained stable during the whole follow-up period. Compared with implanted nontreated animals, the hearing threshold shift decreased by 12 dB in animals treated with methylprednisolone.
authors.affiliation: Inserm UMR-S Minimal Invasive Robot-Based Otologic Surgery, Paris, France. stephaniequesnel@free.fr
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Quesnel
authors.forename: Yann
authors.initials: Y
authors.lastname: Nguyen
authors.forename: Monique
authors.initials: M
authors.lastname: Elmaleh
authors.forename: Alexis Bozorg
authors.initials: AB
authors.lastname: Grayeli
authors.forename: Evelyne
authors.initials: E
authors.lastname: Ferrary
authors.forename: Olivier
authors.initials: O
authors.lastname: Sterkers
authors.forename: Vincent
authors.initials: V
authors.lastname: Couloigner
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001309:Auditory Threshold / Q000187:drug effects*; D019929:Cochlear Implantation; D004195:Disease Models, Animal; D004567:Electrodes, Implanted; D016057:Evoked Potentials, Auditory, Brain Stem / Q000187:drug effects* / Q000502:physiology; D006168:Guinea Pigs; D007273:Injections, Intramuscular; D008297:Male; D008776:Methylprednisolone Hemisuccinate / Q000494:pharmacology*; D011292:Premedication; D014057:Tomography, X-Ray Computed
chemical_list: D000893:Anti-Inflammatory Agents; D008776:Methylprednisolone Hemisuccinate