Acute pulmonary embolism: ancillary findings at spiral CT.

Abstract

To determine the value of parenchymal findings at contrast material-enhanced spiral computed tomography (CT) in patients suspected to have pulmonary embolism (PE). Eighty-eight patients suspected to have PE underwent contrast-enhanced spiral CT and ventilation-perfusion scintigraphy. Concordance between CT and scintigraphic results was used to diagnose or exclude PE. Pulmonary angiography was attempted in all patients with discordant CT and scintigraphic results or indeterminate scans. Parenchymal CT scans were assessed by two radiologists who were not aware of the diagnosis and who had access only to lung window images. Twenty-six patients had PE; 62 did not. Wedge-shaped pleural-based consolidation was seen in 16 patients with PE (62%) and 17 patients without PE (27%) (P < .05) (sensitivity, 62%; specificity, 73%). Linear bands were seen in 12 patients with PE (46%) and 13 patients without PE (21%) (P < .05) (sensitivity, 46%; specificity, 79%). There was no statistically significant difference in the frequency of non-wedge-shaped consolidation, areas of decreased attenuation, or atelectasis. Central and lower-lobe segmental pulmonary arteries that contained emboli were enlarged (P < .05). Parenchymal findings may suggest further investigations when results of spiral CT are inconclusive in diagnosis of PE.