title: Surgical invasiveness of cell transplantation into the guinea pig cochlear modiolus.
abstract: OBJECTIVE
  Previous studies have demonstrated the potential of cell transplantation for regeneration of spiral ganglion neurons (SGNs). However, the effect of surgical invasion on host cochleae has yet to be evaluated. The present study investigated the efficiency and invasiveness of our surgical procedure using a fine glass pipette for injections into the cochlear modiolus.
  
  
  METHODS
  We examined the survival of transplanted embryonic stem cell-derived neurons in the cochlear modiolus of guinea pigs. Surgical invasiveness was assessed by measurements of electrically evoked auditory brainstem responses (eABRs) and SGN densities after an injection of 5 microl of saline into the cochlear modiolus.
  
  
  RESULTS
  All of the transplanted animals exhibited localization of transplanted cells in the cochlear modiolus. No significant alterations in the eABR thresholds or SGN densities were found following surgery.
  
  
  CONCLUSIONS
  These findings indicate that our procedure is a viable method for testing the potential of transplants for SGN replacement.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Ogita
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nakagawa
authors.forename: Kyu Yup
authors.initials: KY
authors.lastname: Lee
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Inaoka
authors.forename: Takayuki
authors.initials: T
authors.lastname: Okano
authors.forename: Yayoi S
authors.initials: YS
authors.lastname: Kikkawa
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Juichi
authors.initials: J
authors.lastname: Ito
mesh_terms: D000818:Animals; D002452:Cell Count; D002454:Cell Differentiation; D002470:Cell Survival; D017690:Cell Transplantation / Q000379:methods*; D003051:Cochlea / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D004056:Differential Threshold; D053595:Embryonic Stem Cells / Q000473:pathology / Q000637:transplantation*; D016057:Evoked Potentials, Auditory, Brain Stem; D006168:Guinea Pigs; D007267:Injections; D019060:Minimally Invasive Surgical Procedures; D009474:Neurons / Q000473:pathology*; D011184:Postoperative Period; D012965:Sodium Chloride / Q000008:administration & dosage; D013136:Spiral Ganglion / Q000473:pathology; D016896:Treatment Outcome
chemical_list: D012965:Sodium Chloride