title: Do preliminary chest X-ray findings define the optimum role of pulmonary scintigraphy in suspected pulmonary embolism?
abstract: OBJECTIVE
  To investigate if preliminary chest radiograph (CXR) findings can define the optimum role of lung scintigraphy in subjects investigated for pulmonary embolism (PE).
  
  
  METHODS
  The CXR and scintigraphy findings from 613 consecutive subjects investigated for suspected PE were retrieved from a radiological database. Of 393 patients with abnormal CXRs, a subgroup of 238 was examined and individual radiographic abnormalities were characterized. CXR findings were related to the scintigraphy result.
  
  
  RESULTS
  Scintigraphy was normal in 286 subjects (47%), non-diagnostic in 207 (34%) and high probability for PE in 120 (20%). In 393 subjects (64%) the preliminary CXR was abnormal and 188 (48%) of scintigrams in this group were non-diagnostic. Individual radiographic abnormalities were not associated with significantly different scintigraphic outcomes. If the preliminary CXR was normal (36%), the proportion of non-diagnostic scintigrams decreased to 9% (19 of 220 subjects) (P < 0.05).
  
  
  CONCLUSIONS
  In subjects investigated for PE, an abnormal CXR increases the prevalence of non-diagnostic scintigrams. A normal pre-test CXR is more often associated with a definitive (normal or high probability) scintigram result. The chest radiograph may be useful in deciding the optimum sequence of investigations.Forbes, K. P. N., Reid, J. H., Murchison, J. T.(2001). Clinical Radiology56, 397-400.
authors.affiliation: Department of Radiology, Royal Infirmary of Edinburgh, 1 Lauriston Place, Edinburgh EH3 9YW, U.K.
authors.forename: K P
authors.initials: KP
authors.lastname: Forbes
authors.forename: J H
authors.initials: JH
authors.lastname: Reid
authors.forename: J T
authors.initials: JT
authors.lastname: Murchison
mesh_terms: D016009:Chi-Square Distribution; D006801:Humans; D016014:Linear Models; D011237:Predictive Value of Tests; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed