[The diagnosis of acute pulmonary embolism: a comparison between spiral CT and DSA in an animal experiment]

Abstract

Purpose: The value of helical computed tomography (CT) for diagnosis of acute pulmonary embolism was assessed and compared with digital subtraction angiography (DSA) as a reference method.

Material and methods: In 11 dogs, lobar, segmental, and subsegmental occlusions of the pulmonary arteries were produced. Subsequent to selective pulmonary angiography, the animals were examined with contrast-enhanced helical CT.

Results: In the main and lobar pulmonary arteries there was a complete correlation between CT and DSA in documentation of total and partial embolic occlusions. Identification of segmental and subsegmental pulmonary emboli by CT required a second run with optimized parameters in 7 of 11 cases. Nevertheless, 18% of the peripheral arteries could not be classified.

Conclusion: Helical CT as less invasive modality is competitive with DSA in demonstration of central pulmonary emboli. However, CT imaging of peripheral pulmonary emboli requires optimal bolus timing.