title: Effect of intratympanic dexamethasone administration on cisplatin-induced ototoxicity in adult guinea pigs.
abstract: OBJECTIVE
  To evaluate the effect and safety of intratympanic dexamethasone administration on cisplatin-induced ototoxicity in adult male guinea pigs and to assess the differences between early and late protection from this ototoxicity.
  
  
  METHODS
  Forty eight adult male guinea pigs were divided as follows: group I served as control group. Group II was subjected to intratympanic saline (subgroup IIa) or dexamethasone (subgroup IIb) injection. Group III was intraperitoneally injected with cisplatin. Groups IV and V were subjected first to intratympanic dexamethasone administration in both ears for 5 days starting 1 day and 1h - respectively - before cisplatin intraperitoneal injection.
  
  
  RESULTS
  Dexamethasone intratympanic injection revealed similar functional and structural results compared with control. Cisplatin intraperitoneal injection resulted in a profound cochlear functional and structural damage in group III. Non-significant otoprotection resulted from intratympanic dexamethasone administration one day before cisplatin. Intratympanic dexamethasone injection 1h before cisplatin treatment resulted in a significant preservation of the functional and structural properties of the cochlea.
  
  
  CONCLUSIONS
  Intratympanic dexamethasone administration is a safe, easy and efficient way to protect from cisplatin ototoxicity especially when administered 1h before cisplatin treatment.
authors.affiliation: Otolaryngology Departments, Faculty of Medicine, Ain Shams University, Cairo, Egypt. amrgouda@hotmail.com
authors.forename: Amr G
authors.initials: AG
authors.lastname: Shafik
authors.forename: Rasha H
authors.initials: RH
authors.lastname: Elkabarity
authors.forename: Mirahan T
authors.initials: MT
authors.lastname: Thabet
authors.forename: Nevine B
authors.initials: NB
authors.lastname: Soliman
authors.forename: Nagwa K
authors.initials: NK
authors.lastname: Kalleny
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001309:Auditory Threshold / Q000187:drug effects; D002945:Cisplatin / Q000008:administration & dosage / Q000009:adverse effects*; D003051:Cochlea / Q000187:drug effects* / Q000473:pathology; D003907:Dexamethasone / Q000008:administration & dosage*; D004195:Disease Models, Animal; D016057:Evoked Potentials, Auditory, Brain Stem; D005938:Glucocorticoids / Q000008:administration & dosage*; D006168:Guinea Pigs; D034381:Hearing Loss / Q000139:chemically induced / Q000517:prevention & control*; D007267:Injections; D008297:Male; D008853:Microscopy; D008855:Microscopy, Electron, Scanning; D014432:Tympanic Membrane
chemical_list: D000970:Antineoplastic Agents; D005938:Glucocorticoids; D003907:Dexamethasone; D002945:Cisplatin