Diagnostic value of ventilation-perfusion lung scanning in patients with suspected pulmonary embolism

Chest. 1985 Dec;88(6):819-28. doi: 10.1378/chest.88.6.819.


Differing opinions about the value of ventilation-perfusion lung scanning have created controversy concerning the correct approach to the diagnosis of pulmonary embolism. In a prospective study of 305 consecutive patients with clinically suspected pulmonary embolism and abnormal perfusion lung scans, we evaluated the role of ventilation-perfusion lung scanning, pulmonary angiography, and objective testing for venous thrombosis in the diagnostic process. Segmental or greater perfusion defects with ventilation mismatch have a high probability (86 percent) of pulmonary embolism. Contrary to current clinical practice, however, the approach of ruling against pulmonary embolism by a "low probability" scan pattern is incorrect, even with an improved technique for ventilation imaging; the frequency of pulmonary embolism in these patients ranged from 25 to 40 percent. Objective testing for venous thrombosis provides a practical alternative to performing pulmonary angiography in the diagnostic work-up; by providing an endpoint for commencing anticoagulant therapy, a positive result obviates the need for further testing in 20 to 30 percent of patients.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Bayes Theorem
  • Diagnosis, Differential
  • Evaluation Studies as Topic
  • Female
  • Humans
  • Lung / diagnostic imaging
  • Male
  • Middle Aged
  • Plethysmography, Impedance
  • Prospective Studies
  • Pulmonary Embolism / diagnostic imaging*
  • Radionuclide Imaging
  • Thrombophlebitis / diagnostic imaging
  • Ventilation-Perfusion Ratio*