title: Association of anatomic variations with antrochoanal polyps in paranasal sinus computed tomography scan.
abstract: BACKGROUND
  This study was designed to determine the prevalence of concomitant anatomic variation of paranasal sinuses in patients with antrochoanal polyp (ACP).
  
  
  METHODS
  Among patients referred by their clinicians for standard computed tomography scan of paranasal sinuses septal deviation, concha bullosa, and retention cyst were evaluated in both patients with ACP as well as in a control group.
  
  
  RESULTS
  Of the 17 patients with ACP, fifteen patients (88.2%) had septal deviation and two patients (11.8%) had concha bullosa. None of the patients with ACP had retention cyst or hypertrophic turbinate. Of the 78 patients in control group, twenty-nine (37.2%) had septal deviation, six (7.7%) had concha bullosa, seven (8.9%) had retention cyst, and one (1.2%) had hypertrophic turbinate. Septal deviation in patients with ACP has higher incidence (P< 0.001).
  
  
  CONCLUSIONS
  This study showed that septal deviation is an anatomic variation which is significantly concomitant with ACP. Larger studies are needed to show the role of other anatomic variations in patients with ACP.
authors.affiliation: Department of Radiology, Alzahra Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Hekmatnia
authors.affiliation: Department of Radiology, Alzahra Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Farid
authors.initials: F
authors.lastname: Shirvani
authors.affiliation: Department of Radiology, Alzahra Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Farhad
authors.initials: F
authors.lastname: Mahmoodi
authors.affiliation: Department of Otolaryngology, Alzahra Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Hashemi
keywords: Antrochoanal polyp; computed tomography scan; paranasal sinus