title: Clinical importance of the Korner's septum.
abstract: OBJECTIVE
  To evaluate the clinical importance of the petrosquamosal lamina (Korner's septum [KS]), which is not only a bony plate dividing the mastoid cells at the level of antrum, but is also a lamina starting from the posterior aspect of the glenoid fossa that extends above the middle ear cavity and courses in an inferior direction lateral to the facial canal and proceeds to the mastoid apex.
  
  
  METHODS
  A retrospective review of 688 mastoidectomies performed in University Hospital from 1987 to 1992.
  
  
  METHODS
  The study group consisted of 389 males and 299 females (mean age 30.85 +/- 12.80, the youngest being 8 and the oldest being 67 years of age).
  
  
  METHODS
  The main outcome measures were the prevalence of KS encountered during mastoidectomies and comparison of prevalence of retraction pockets (RPs) or retraction and/or adhesion of the whole tympanic membrane (R/A-TM) between ears with KS and without KS.
  
  
  RESULTS
  The prevalence of KS was 30.4% among the ears with RP or R/A-TM, 6.58% in normal ears, and 17.4% in ears with chronic otitis media without RP or R/A-TM.
  
  
  CONCLUSIONS
  KS is an important anatomic handicap predisposing the individual to chronic otitis media, particularly when it is characterized by attic retraction pockets and cholesteatoma, and adhesive otitis media, because KS contributes to attic blockage. This statement is in accordance with the original articles written by Cheatle (1910, 1923) and Williams (1966), and recently published data related to supratubal recess and the cog (Tono et al., 1996).
authors.affiliation: Faculty of Medicine, Department of Otorhinolaryngology-Head and Neck Surgery, Gazi University, Ankara, Turkey.
authors.forename: N
authors.initials: N
authors.lastname: Göksu
authors.forename: Y K
authors.initials: YK
authors.lastname: Kemaloğlu
authors.forename: A
authors.initials: A
authors.lastname: Köybaşioğlu
authors.forename: F
authors.initials: F
authors.lastname: Ileri
authors.forename: S
authors.initials: S
authors.lastname: Ozbilen
authors.forename: N
authors.initials: N
authors.lastname: Akyildiz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004432:Ear, Middle / Q000002:abnormalities*; D005158:Facial Paralysis; D005260:Female; D006801:Humans; D008297:Male; D008416:Mastoid / Q000601:surgery; D008575:Meniere Disease; D008875:Middle Aged; D010033:Otitis Media; D012189:Retrospective Studies