title: Detection of the petrosquamosal sinus in chronic otitis media using high-resolution CT.
abstract: OBJECTIVE
  To evaluate the prevalence of the persistent petrosquamosal venous sinus in patients with chronic otitis media using a high-resolution CT scan.
  
  
  METHODS
  Retrospective chart review.
  
  
  METHODS
  Tertiary referral center.
  
  
  METHODS
  Eighty-four patients older than 6 years of age underwent surgery (in a total of 92 ears) for chronic otitis media at Kyoto University Hospital, Department of Otolaryngology-Head and Neck Surgery. We used high-resolution CT scans to evaluate the prevalence and size of persistent petrosquamosal sinuses, as well as their relative position to the middle fossa.
  
  
  RESULTS
  A petrosquamosal sinus was detected in 42 (45.7%), a higher frequency than in ears without chronic otitis media (10.3%). The diameter of the sinuses was <1.0 mm in 20 ears, 1.0 mm to 2.0 mm in 17 ears, and >2.0 mm in 5 ears. The petrosquamosal sinus was positioned inferior to the lowest part of the middle fossa in 10 ears.
  
  
  CONCLUSIONS
  The petrosquamosal sinus was detected frequently in high-resolution CT scans in patients with chronic otitis media. In approximately half of the patients, the sinus was larger than 1 mm in diameter and may be encountered during mastoidectomy.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan. hhiraumi@ent.kuhp.kyoto-u.ac.jp
authors.forename: Harukazu
authors.initials: H
authors.lastname: Hiraumi
authors.forename: Akira
authors.initials: A
authors.lastname: Yamamoto
authors.forename: Norio
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Juichi
authors.initials: J
authors.lastname: Ito
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002908:Chronic Disease; D003392:Cranial Sinuses / Q000000981:diagnostic imaging* / Q000196:embryology; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010033:Otitis Media / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000601:surgery*; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D015995:Prevalence; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome
keywords: chronic otitis media; high-resolution CT scan; petrosquamosal sinus