Spiral CT angiography is an accurate method for the detection and exclusion of PE, with the exception of isolated subsegmental PE.

The use of spiral CT angiography is likely to reduce the mortality and improve cost-effectiveness in the diagnostic work-up of suspected pulmonary embolism.

The aim of our study was to compare the diagnostic value of helical CT vs that of ventilation-perfusion (V/Q) scintigraphy as a first-line test in a diagnostic strategy in patients suspected of pulmonary embolism (PE). In a retrolective-prolective cohort study we tested the accuracy of helical CT vs V/Q scintigraphy in 123 patients suspected of PE. A diagnostic panel was asked to formulate the presumptive diagnosis on the presence or absence of PE, or of alternative disease by using two competing diagnostic strategies. These consisted of the patient history, laboratory tests and chest X-ray (together baseline tests) in combination with either helical CT or V/Q scintigraphy (CT strategy and V/Q strategy, respectively). The results were compared with the final diagnosis in each patient that was established from various reference tests (which included V/Q scintigraphy, pulmonary angiography and clinical follow-up). The CT and V/Q strategies were compared with regard to the accuracy for PE, for alternative diseases and with regard to the proportion of conclusive diagnoses that were made. The CT strategy was more accurate than the V/Q strategy for detecting or excluding PE. Sensitivity and specificity were 49 and 74 % for the V/Q strategy and 75 and 90 % for the CT strategy, respectively (P = 0.01). The CT strategy provided a conclusive diagnosis in a significantly larger proportion of patients than the V/Q strategy, 92 vs 72 % (P< 0.001). The CT strategy detected more alternative diagnosis than the V/Q strategy, 93 vs 51 %, respectively (P < 0.001). Helical CT seems more useful than V/Q scintigraphy as a first-line test in patients suspected of PE.

Background -A study was carried out to evaluate the potential place of spiral volumetric computed tomography (SVCT) in the diagnostic strategy for pulmonary embolism. Methods -In a prospective study 249 patients with clinical suspicion of pulmonary embolism were evaluated with various imaging techniques. In all patients

The purpose of this study was to determine the prevalence of lower extremity deep venous thrombosis (DVT) in patients with suspected and proven pulmonary embolism (PE). A meta-analysis was performed, based on literature from January 1983 to June 1997. Papers obtained from a computer-aided literature search were divided into studies with pulmonary angiography or ventilation-perfusion (V/Q) scintigraphy as the reference study. Our own observational data of the prevalence of DVT in 149 patients suspected of PE were also reported. The estimated prevalence of DVT in patients with proven and suspected PE was calculated. In the 149 patients studied, the prevalence of DVT was 12% with suspected PE and 32% (95% confidence interval 20-46%) in patients with proven PE. The individual studies showed a considerable heterogeneity, the prevalence of DVT in proven PE ranged from 10 to 93%. The pooled estimate of the prevalence of DVT in patients suspected of PE, over all studies, was 18% (95% confidence interval 15-20%). The DVT prevalence in proven PE was 36% (95% confidence interval 22-52%) in the angiography-based studies, and 45% (95% confidence interval 33-58%) in the V/Q scintigraphy-based studies. In conclusion, the current meta-analysis shows that the prevalence of DVT in suspected PE is approximately 18%, and in proven PE 36-45%.