title: The prevalence of clinically relevant incidental findings on chest computed tomographic angiograms ordered to diagnose pulmonary embolism.
abstract: BACKGROUND
  Chest computed tomographic angiograms (CTAs) are frequently ordered for evaluation of suspected pulmonary embolism (PE) in the emergency department, but non-PE findings are often noted. Our objective was to determine the prevalence and management implications of incidental findings on chest CTAs ordered to assess for PE.
  
  
  METHODS
  In a cross-sectional study, we reviewed 589 pulmonary CTAs that were ordered in the emergency department of a tertiary care hospital. We measured the prevalence of PE and placed other findings into the following 3 categories: (1) findings that provided potential alternative explanations for acute symptoms, (2) incidental findings that required clinical or radiologic follow-up, and (3) other findings that required less urgent or no follow-up. We reviewed all newly diagnosed pulmonary nodules and significant thoracic adenopathy and determined standard recommended clinical follow-up.
  
  
  RESULTS
  Pulmonary embolism was found in 55 of 589 CTAs (9%). A total of 195 CTAs (33%) had findings that supported alternative diagnoses. A total of 141 patients (24%) had a new incidental finding that required diagnostic follow-up, including 73 patients (13%) with a new pulmonary nodule and 51 patients (9%) with new adenopathy. Using current clinical guidelines, follow-up computed tomography or another procedure would be recommended for 96% of patients with new incidental pulmonary nodules.
  
  
  CONCLUSIONS
  The CTAs that are ordered in the emergency department are more than twice as likely to find an incidental pulmonary nodule or adenopathy than a PE. Systematic approaches should be developed to help primary care physicians contend with a growing number of clinically relevant incidental radiologic findings.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of North Carolina at Chapel Hill, Campus Box 7020, 130 Mason Farm Rd, Chapel Hill, NC 27514. scarson@med.unc.edu.
authors.forename: William B
authors.initials: WB
authors.lastname: Hall
authors.forename: Sherstin G
authors.initials: SG
authors.lastname: Truitt
authors.forename: Leslie P
authors.initials: LP
authors.lastname: Scheunemann
authors.forename: Sidharth A
authors.initials: SA
authors.lastname: Shah
authors.forename: M Patricia
authors.initials: MP
authors.lastname: Rivera
authors.forename: Leonard A
authors.initials: LA
authors.lastname: Parker
authors.forename: Shannon S
authors.initials: SS
authors.lastname: Carson
mesh_terms: D000046:Academic Medical Centers; D000328:Adult; D000368:Aged; D000792:Angiography; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D004417:Dyspnea / Q000209:etiology; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000209:etiology; D033162:Incidental Findings; D008175:Lung Neoplasms / Q000150:complications / Q000000981:diagnostic imaging*; D008206:Lymphatic Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D008297:Male; D008479:Mediastinal Neoplasms / Q000150:complications / Q000000981:diagnostic imaging*; D008875:Middle Aged; D009369:Neoplasms / Q000000981:diagnostic imaging; D015995:Prevalence; D011651:Pulmonary Artery / Q000000981:diagnostic imaging*; D011655:Pulmonary Embolism / Q000150:complications / Q000000981:diagnostic imaging*; D013610:Tachycardia / Q000209:etiology; D014057:Tomography, X-Ray Computed