title: A deep azygoesophageal recess may increase the risk of secondary spontaneous pneumothorax.
abstract: OBJECTIVE
  The azygoesophageal recess (AER) is known as a possible cause of bulla formation in patients with spontaneous pneumothorax. However, there has been little focus on the depth of the AER. We evaluated the relationship between the depth of the AER and pneumothorax development.
  
  
  METHODS
  We conducted a retrospective study of 80 spontaneous pneumothorax patients who underwent surgery at our institution. We evaluated the depth of the AER on preoperative computed tomography scans.
  
  
  RESULTS
  Ruptured bullae at the AER were found in 12 patients (52.2%) with secondary spontaneous pneumothorax (SSP) and 8 patients (14.0%) with primary spontaneous pneumothorax (PSP) (p < 0.001). In patients with ruptured bullae at the AER, 10 SSP patients (83.3%) had a deep AER while only 2 PSP patients (25%) had a deep AER (p = 0.015).
  
  
  CONCLUSIONS
  A deep AER was more frequently associated with SSP than with PSP. A deep AER may contributes to bulla formation and rupture in SSP patients.
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. ttakahashi-tks@umin.ac.jp.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Kawashima
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Kuwano
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Nagayama
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Jyunichi
authors.initials: J
authors.lastname: Nitadori
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Anraku
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Sato
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.|Department of Thoracic Surgery, Kansai Medical University, 2-3-1 Shinmachi, Hirakata, Osaka, 573-1191, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Murakawa
authors.affiliation: Department of Thoracic Surgery, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Nakajima
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001768:Blister / Q000209:etiology; D003964:Diaphragm / Q000002:abnormalities* / Q000000981:diagnostic imaging; D004947:Esophagus / Q000002:abnormalities* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male; D008482:Mediastinum / Q000002:abnormalities* / Q000000981:diagnostic imaging; D008875:Middle Aged; D010994:Pleura / Q000002:abnormalities* / Q000000981:diagnostic imaging; D011030:Pneumothorax / Q000209:etiology* / Q000601:surgery*; D012189:Retrospective Studies; D012306:Risk; D019616:Thoracic Surgical Procedures; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: Emphysema/bullae; Mediastinum pneumothorax