title: Value of lateral neck radiography for ingested foreign bodies using the likelihood ratio.
abstract: OBJECTIVE
  To determine the diagnostic accuracy of lateral neck radiography and its value in related radiographic findings in the detection of foreign bodies using the likelihood ratio.
  
  
  METHODS
  This retrospective study comprised 114 patients who had neck radiography followed by rigid esophagoscopy. Interpretations of the radiographs were correlated with esophagoscopic findings and clinical follow-up for at least 1 month. Data were mainly assessed by likelihood ratio and detection rate.
  
  
  RESULTS
  Plain radiography had a positive likelihood ratio of 2.4 (95% confidence interval [CI] 1.8-3.1) and a negative likelihood ratio of 0.6 (95% CI 0.40-0.7). It had a sensitivity of 57.4% (95% CI 45.6-69.1) and a specificity of 76.1% (95% CI 63.8-88.4). Positive likelihood ratios for each radiographic finding (foreign body shadow, air, and soft tissue swelling) were 3.4 (95% CI 2.6-4.4), 1.5 (95% CI 0.9-2.6), and 4.1 (95% CI 1.9-8.7), respectively. Plain radiography had a high detection rate (72.5%) when foreign bodies were lodged in the hypopharynx and cervical esophagus. On the contrary, the detection rate was poor (0%) in the oropharynx.
  
  
  CONCLUSIONS
  A lateral neck radiograph is better taken after a negative finding in a thorough oral examination and fibre-optic laryngoscopy. Judging from the possible site of impacted foreign body and radiographic findings, we can better predict the presence of foreign bodies.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Changhua Christian Hospital, Changhua, Taiwan.
authors.forename: Iuan-Sheng
authors.initials: IS
authors.lastname: Wu
authors.forename: Tzu-Lung
authors.initials: TL
authors.lastname: Ho
authors.forename: Cheng-Chaun
authors.initials: CC
authors.lastname: Chang
authors.forename: Hong-Shan
authors.initials: HS
authors.lastname: Lee
authors.forename: Mu-Kuan
authors.initials: MK
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001842:Bone and Bones; D004945:Esophagoscopy; D004947:Esophagus / Q000000981:diagnostic imaging*; D005260:Female; D005399:Fishes; D005547:Foreign Bodies / Q000000981:diagnostic imaging*; D006801:Humans; D007013:Hypopharynx / Q000000981:diagnostic imaging*; D007828:Laryngoscopy; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D009333:Neck / Q000000981:diagnostic imaging*; D009960:Oropharynx / Q000000981:diagnostic imaging*; D011859:Radiography; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult