title: Short-term Peripheral Auditory Effects of Cranial Irradiation: A Mouse Model.
abstract: OBJECTIVE
  Assess postcranial irradiation: (1) short-term threshold shift, (2) short-term peripheral auditory histopathology, and (3) the mouse as an experimental model.
  
  
  METHODS
  Adult mice were exposed to single-dose radiation of 10 to 60 Gy. Pre- and post-irradiation (baseline, 2-8 days) audiometric brainstem response data were recorded with analysis of cochlear ultrastructure.
  
  
  RESULTS
  Significant threshold shift occurred at all test frequencies in mice exposed to ≥20 Gy at 4 to 6 days post-irradiation. Ultrastructurally in Rosenthal's canal and the spiral lamina, neuronal density and extracellular matrix decreased dramatically. There was overall preservation of hair cells, stria vascularis, and vasculature. No difference within Gy group was noted in the frequency or severity of pathology along the length of the cochlea.
  
  
  CONCLUSIONS
  The initial impact of radiation in the first week post-exposure focuses on spiral ganglion cell bodies and peripheral projections, resulting in significant threshold shift for irradiation dosages≥20 Gy. This study demonstrates that the mouse is a viable model for study of short-term peripheral auditory effects using single-dose cranial irradiation. Additionally, with access to a precise animal irradiator, the mouse may be used as an experimental model for a fractionated irradiation dosage of 10 Gy, simulating stereotactic therapeutic cranial irradiation.
authors.affiliation: Department of Otolaryngology Head-Neck Surgery, Saint Louis University, St. Louis, Missouri, USA.
authors.forename: Krysta L
authors.initials: KL
authors.lastname: Gasser Rutledge
authors.affiliation: Department of Otolaryngology Head-Neck Surgery, Saint Louis University, St. Louis, Missouri, USA.
authors.forename: Kumar G
authors.initials: KG
authors.lastname: Prasad
authors.affiliation: Department of Otolaryngology Head-Neck Surgery, Saint Louis University, St. Louis, Missouri, USA.
authors.forename: Kara R
authors.initials: KR
authors.lastname: Emery
authors.affiliation: Department of Otolaryngology Head-Neck Surgery, Saint Louis University, St. Louis, Missouri, USA.
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Mikulec
authors.affiliation: Department of Otolaryngology Head-Neck Surgery, Saint Louis University, St. Louis, Missouri, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Varvares
authors.affiliation: Department of Otolaryngology Head-Neck Surgery, Saint Louis University, St. Louis, Missouri, USA mgratton@slu.edu.
authors.forename: Michael Anne
authors.initials: MA
authors.lastname: Gratton
mesh_terms: D000818:Animals; D001309:Auditory Threshold / Q000528:radiation effects; D003051:Cochlea / Q000473:pathology / Q000528:radiation effects; D016371:Cranial Irradiation / Q000009:adverse effects* / Q000379:methods; D016057:Evoked Potentials, Auditory, Brain Stem / Q000528:radiation effects; D051379:Mice; D011833:Radiation Injuries, Experimental; D013136:Spiral Ganglion / Q000473:pathology / Q000528:radiation effects
keywords: auditory brainstem response; cochlea; cranial irradiation; hearing loss; mouse model; short-term radiation effects