title: Giant bulla formation in the lung because of a check-valve mechanism.
abstract: The pathogenesis of bulla formation has not yet been demonstrated in pathologic examinations or through direct visualization during thoracotomy or thoracoscopic surgery. We present two cases of giant bulla formation after pneumothorax because of cryptogenic organizing pneumonia and lung abscess. The case findings suggested that the pathogenesis was attributable to a check-valve mechanism, secondary to bronchiolitis obliterans, or the presence of an obstructing air leakage due to a lung fistula. The lung fistula had been covered by inflammatory membranes consisting of blood and/or fibrous precipitates with detached visceral pleura.
authors.affiliation: Department of Respiratory Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka City, Tokyo 181-8611, Japan. Electronic address: jkhwq282@yahoo.co.jp.
authors.forename: Aya
authors.initials: A
authors.lastname: Hirata
authors.affiliation: Department of Respiratory Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka City, Tokyo 181-8611, Japan. Electronic address: sara@yd5.so-net.ne.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Saraya
authors.affiliation: Department of General Thoracic Surgery, Kyorin University School of Medicine, Japan. Electronic address: ishaninare@mail.goo.ne.jp.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Arai
authors.affiliation: Department of General Thoracic Surgery, Kyorin University School of Medicine, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Karita
authors.affiliation: Department of General Thoracic Surgery, Kyorin University School of Medicine, Japan. Electronic address: rkawachi2@gmail.com.
authors.forename: Riken
authors.initials: R
authors.lastname: Kawachi
authors.affiliation: Department of General Thoracic Surgery, Kyorin University School of Medicine, Japan. Electronic address: htakei@ks.kyorin-u.ac.jp.
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Takei
authors.affiliation: Department of Respiratory Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka City, Tokyo 181-8611, Japan. Electronic address: kobu0805@gmail.com.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Ohkuma
authors.affiliation: Department of Respiratory Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka City, Tokyo 181-8611, Japan. Electronic address: matsu.manabu@gmail.com.
authors.forename: Manabu
authors.initials: M
authors.lastname: Ishida
authors.affiliation: Department of Pathology, Kyorin University School of Medicine, Japan. Electronic address: masachi@ks.kyorin-u.ac.jp.
authors.forename: Masachika
authors.initials: M
authors.lastname: Fujiwara
authors.affiliation: Department of Respiratory Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka City, Tokyo 181-8611, Japan. Electronic address: hajime@ks.kyorin-u.ac.jp.
authors.forename: Hajime
authors.initials: H
authors.lastname: Takizawa
mesh_terms: D000368:Aged; D001768:Blister / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D018549:Cryptogenic Organizing Pneumonia / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008169:Lung Abscess / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011030:Pneumothorax / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D014057:Tomography, X-Ray Computed
keywords: Bulla formation; Check-valve mechanism; Cryptogenic organizing pneumonia; Organizing pneumonia; Pneumothorax