title: Barium appendicitis: A single institution review in Japan.
abstract: OBJECTIVE
  To review clinical experience with barium appendicitis at a single institution.
  
  
  METHODS
  A retrospective review of patients admitted with a diagnosis of acute appendicitis, from January 1, 2013 to December 31, 2015 was performed. Age, gender, computed tomography (CT) scan findings if available, past history of barium studies, pathology, and the presence of perforation or the development of complications were reviewed. If the CT scan revealed high density material in the appendix, the maximum CT scan radiodensity of the material is measured in Hounsfield units (HU). Barium appendicitis is defined as: (1) patients diagnosed with acute appendicitis; (2) the patient has a history of a prior barium study; and (3) the CT scan shows high density material in the appendix. Patients who meet all three criteria are considered to have barium appendicitis.
  
  
  RESULTS
  In total, 396 patients were admitted with the diagnosis of acute appendicitis in the study period. Of these, 12 patients (3.0%) met the definition of barium appendicitis. Of these 12 patients, the median CT scan radiodensity of material in the appendix was 10000.8 HU, ranging from 3066 to 23423 HU (± 6288.2). In contrast, the median CT scan radiodensity of fecaliths in the appendix, excluding patients with barium appendicitis, was 393.1 HU, ranging from 98 to 2151 HU (± 382.0). The CT scan radiodensity of material in the appendices of patients with barium appendicitis was significantly higher than in patients with nonbarium fecaliths (P< 0.01).
  
  
  CONCLUSIONS
  Barium appendicitis is not rare in Japan. Measurement of the CT scan radiodensity of material in the appendix may differentiate barium appendicitis from routine appendicitis.
authors.affiliation: Hideki Katagiri, Tadao Kubota, Ken Mizokami, Department of Surgery, Tokyo Bay Urayasu Ichikawa Medical Center, Urayasu city, Chiba 279-0001, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Katagiri
authors.affiliation: Hideki Katagiri, Tadao Kubota, Ken Mizokami, Department of Surgery, Tokyo Bay Urayasu Ichikawa Medical Center, Urayasu city, Chiba 279-0001, Japan.
authors.forename: Alan Kawarai
authors.initials: AK
authors.lastname: Lefor
authors.affiliation: Hideki Katagiri, Tadao Kubota, Ken Mizokami, Department of Surgery, Tokyo Bay Urayasu Ichikawa Medical Center, Urayasu city, Chiba 279-0001, Japan.
authors.forename: Tadao
authors.initials: T
authors.lastname: Kubota
authors.affiliation: Hideki Katagiri, Tadao Kubota, Ken Mizokami, Department of Surgery, Tokyo Bay Urayasu Ichikawa Medical Center, Urayasu city, Chiba 279-0001, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Mizokami
keywords: Acute appendicitis; Barium appendicitis; Barium sulfate; Gastric cancer screening; Upper gastrointestinal imaging