Radiology, Vol 194, 313-319, Copyright © 1995 by Radiological Society of North America
Pulmonary embolism: diagnosis with contrast-enhanced electron-beam CT and comparison with pulmonary angiography
CL Teigen, TP Maus, PF Sheedy 2nd, AW Stanson, CM Johnson, JF Breen and MA McKusick
Department of Diagnostic Radiology, Mayo Clinic, Rochester, MN 55905.
PURPOSE: To determine the sensitivity and specificity of contrast
material-enhanced electron-beam computed tomography (CT) in the diagnosis
of pulmonary embolism (PE). MATERIALS AND METHODS: Sixty patients suspected
of having PE were prospectively evaluated with pulmonary angiography and
contrast-enhanced electron-beam CT. Thirty- eight patients underwent
ventilation-perfusion (V-P [also known as V/Q]) scanning. The pulmonary
vasculature was divided into 12 anatomic zones. CT and angiographic
findings were correlated on a patient-by- patient basis and for each
vascular zone. RESULTS: Both studies were negative for PE in 36 patients.
Both studies were positive in 15 patients, with the site of the emboli
correlating well. Prospective sensitivity of CT was 65%; specificity, 97%;
positive predictive value, 94%; and negative predictive value, 82%. After
review of the nine discordant cases, sensitivity and specificity approached
100% for clinically important acute PE. CT depicted central and peripheral
emboli equally well. CT was more sensitive and specific than V-P scanning.
CONCLUSION: Electron-beam CT is a sensitive and specific noninvasive method
for the diagnosis of PE. It has the potential to replace V-P scanning as
the primary screening examination for PE.
