title: Ultrastructural analysis of the chorda tympani nerve in chronic suppurative otitis media.
abstract: OBJECTIVE
  To compare ultrastructure of the chorda tympani nerve by light and electron microscopy in patients with otosclerosis and chronic suppurative otitis media.
  
  
  METHODS
  Comparative prospective study.
  
  
  METHODS
  Tertiary care, referral medical center.
  
  
  METHODS
  The tympanic segments of chorda tympani nerves were collected for ultrastructural investigation in 20 cases with chronic suppurative otitis media and 10 cases with otosclerosis that underwent middle ear surgery.
  
  
  RESULTS
  Histopathologic examinations of the suppurative group showed that unmyelinated fibers were almost totally lost and replaced by collagen fibers. The thickness of the myelin sheaths was very slender, whereas some of them were atrophic. A substantial increase was encountered in the endoneural collagen substance and connective tissue, whereas inflammatory elements and edema were present occasionally. Degenerative alterations of the myelinated fibers mainly occurred in the form of adaxonal vacuoles. There was disorganization and separation of parallel lamellae of Schmidt-Lanterman clefts.
  
  
  CONCLUSIONS
  The chorda tympani nerve should be preserved in otologic surgery. However, inadvertent dissection of the chorda tympani nerve in chronic suppurative otitis media surgery will not possibly cause a postoperative disturbance in light of ultrastructural changes that occur in the nerve.
authors.affiliation: Gazi University Faculty of Medicine, ENT Department, Ankara, Turkey. uygur@gazi.edu.tr
authors.forename: Kemal
authors.initials: K
authors.lastname: Uygur
authors.forename: Ismet
authors.initials: I
authors.lastname: Bayramoglu
authors.forename: Aysegul
authors.initials: A
authors.lastname: Nazikoğlu
authors.forename: Metin
authors.initials: M
authors.lastname: Yilmaz
authors.forename: Yildirim
authors.initials: Y
authors.lastname: Bayazit
authors.forename: Sevda
authors.initials: S
authors.lastname: Muftuoglu
mesh_terms: D001369:Axons / Q000473:pathology; D002814:Chorda Tympani Nerve / Q000473:pathology* / Q000601:surgery; D002908:Chronic Disease; D006801:Humans; D008854:Microscopy, Electron; D009410:Nerve Degeneration / Q000473:pathology; D009412:Nerve Fibers / Q000473:pathology; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D010035:Otitis Media, Suppurative / Q000473:pathology* / Q000601:surgery; D010040:Otosclerosis / Q000473:pathology / Q000601:surgery; D011446:Prospective Studies; D012583:Schwann Cells / Q000473:pathology; D013201:Stapes Surgery