title: Posttraumatic pulmonary pseudocyst: computed tomography findings and management in 33 patients.
abstract: BACKGROUND
  Posttraumatic pulmonary pseudocyst (PPP) is a complication of blunt chest trauma and poorly documented. A retrospective review of PPPs observed during the past 6 years in our hospitals is presented in this report.
  
  
  METHODS
  We retrospectively studied the serial chest computed tomographic scans and clinical data of 33 consecutive patients with PPPs.
  
  
  RESULTS
  Fifty-three PPPs from 33 patients were found. Thirty-six PPPs were located in the subpleural pulmonary parenchyma, whereas others were located in the pulmonary parenchyma near other harder structures. Follow-up examinations demonstrated that air-filled cavities and air-fluid cavities could turn into pulmonary hematomas and eventually resolved without specific treatment. The PPPs were resolved in 11 to 82 days. The resolving time of air-fluid cavity (mean, 47.5 days) was significantly longer than the resolving time of air-filled cavity (mean, 16.3 days; p = 0.001). Three patients died of acute respiratory distress syndrome or head trauma. No patient died of PPP. Twelve patients with serious pneumothorax, hemothorax, or both were cured with surgical hemostasis and/or drainage. Eighteen patients resolved without specific treatment.
  
  
  CONCLUSIONS
  Computed tomography increased the frequency of PPP diagnosis and accurately demonstrated the characteristics of the lesions. Air-filled pseudocysts resolved more quickly than those containing fluid. The outcome of PPPs can be favorable without specific treatment. PPP does not require follow-up CT scan or intervention in the absence of complications.
  
  
  METHODS
  Prognostic/epidemiologic study, level V.
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Jinan University, Guangzhou, China. tluolp@jnu.edu.cn
authors.forename: Liangping
authors.initials: L
authors.lastname: Luo
authors.forename: Liang
authors.initials: L
authors.lastname: Yin
authors.forename: Zaosong
authors.initials: Z
authors.lastname: Liu
authors.forename: Ziyun
authors.initials: Z
authors.lastname: Xiang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003560:Cysts / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy*; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D012189:Retrospective Studies; D013898:Thoracic Injuries / Q000150:complications* / Q000000981:diagnostic imaging / Q000628:therapy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014949:Wounds, Nonpenetrating / Q000150:complications* / Q000000981:diagnostic imaging / Q000628:therapy; D055815:Young Adult