title: CT findings of a displaced left upper division bronchus in adults: its importance for performing safe left pulmonary surgery.
abstract: OBJECTIVE
  The aim of this study was to describe the CT findings of a displaced left upper division bronchus (DLUDB) in adults.
  
  
  METHODS
  Ten patients with DLUDB were identified. The following CT features were assessed: origin of the DLUDB; distance between the origin of the DLUDB and the origin of the left upper lobe (LUL) bronchus; height of the origin of the DLUDB against the left pulmonary artery (LPA); difference of the main bronchial length; ventilated segment; course of the left pulmonary artery against the DLUDB; and presence of an accessory fissure or other anomalies.
  
  
  RESULTS
  DLUDB arose from the posterolateral or lateral aspect of the left main bronchus immediately proximal to the origin of the LUL bronchus. It tended to course along the posterior wall of the LPA and to ventilate the apicoposterior segment with or without the anterior segment. The LPA passed between the displaced bronchus and the lingular bronchus. The origin of the DLUDB was located lower than the inferior wall of the proximal LPA in 6 patients. The accessory fissure between the associated segment and remaining part of the LUL and right tracheal bronchus coexisted in 7 and 3 patients respectively.
  
  
  CONCLUSIONS
  DLUDB has characteristic findings on CT. Radiologists should be aware of this entity and inform the surgeon as it can prevent serious complications in a patient who may undergo lobectomy of the left lung.
authors.affiliation: Department of Radiology, National Hospital Organization Okinawa Hospital, 20-14 Ganeko 3-chome, Ginowan city, Okinawa 901-2214, Japan. oshiro4211@yahoo.co.jp
authors.forename: Yasuji
authors.initials: Y
authors.lastname: Oshiro
authors.forename: Sadayuki
authors.initials: S
authors.lastname: Murayama
authors.forename: Morio
authors.initials: M
authors.lastname: Ohta
authors.forename: Takao
authors.initials: T
authors.lastname: Teruya
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001980:Bronchi / Q000002:abnormalities*; D001995:Bronchography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*