title: Prevalence of sphenoid sinus agenesis in adults: a CT scan study.
abstract: OBJECTIVE
  Sphenoid sinus agenesis is a very rare entity. In this study, we evaluated the CT scans of 1193 patients and detected cases with sphenoid sinus agenesis despite the absence of craniofacial anomalies or syndromes.
  
  
  METHODS
  The CT scans of 1193 patients who had undergone endoscopic sinus surgery in our clinic between 1999 and 2008 were retrospectively evaluated. Of the patients, 652 (54.6%) were female and 541 (45.3%) were male. The mean age of the patients was 32 years (range: 13-75 yrs.).
  
  
  RESULTS
  In this study, we identified eight patients (0.67%) with sphenoid agenesis. Three patients (37.5%) had bilateral, 3 patients (37.5%) had left, and 2 patients (25%) had right sphenoid agenesis. None of the patients had craniofacial anomalies or syndromes.
  
  
  CONCLUSIONS
  Sphenoid sinus agenesis is rarely seen in the absence of craniofacial anomalies or syndromes. In our study, its incidence was 0.67%. Awareness of sphenoid sinus agenesis and/or hypoplasia is very important, particularly when transphenoidal hypophysectomy is planned.
authors.affiliation: 1st Otolaryngology Head and Neck Department, Ankara Diskapi Yildirim Beyazit Training and Research Hospital, Irfan Bastug Cad. 06110 Diskapi Ankara, Turkey. didem_ece@yahoo.com
authors.forename: D
authors.initials: D
authors.lastname: Sonbay
authors.forename: C
authors.initials: C
authors.lastname: Saka
authors.forename: I
authors.initials: I
authors.lastname: Akin
authors.forename: B
authors.initials: B
authors.lastname: Gunsoy
authors.forename: A
authors.initials: A
authors.lastname: Gokler
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015331:Cohort Studies; D004724:Endoscopy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D015619:Respiratory System Abnormalities / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000601:surgery; D012189:Retrospective Studies; D013101:Sphenoid Sinus / Q000002:abnormalities* / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed; D055815:Young Adult