[MR imaging of experimental pulmonary embolism using a macromolecular contrast medium].

PURPOSE

To evaluate macromolecular contrast-enhanced MR-angiography for the detection of experimentally induced pulmonary artery embolism and to determine the size of the smallest detectable embolised vessel.

METHODS

Pulmonary artery embolism was artificially induced in eight isolated perfused sheep lungs by injecting room air into the main pulmonary artery. The pulmonary vascular system enhanced by macromolecular gadolinium-DTPA-polylysine was imaged with a flow-sensitive gradient-echo technique.

RESULTS

Pulmonary artery embolism was demonstrated in all eight lungs by an obvious cut-off phenomenon in the contrast-enhanced arteries proximal to the pulmonary air emboli. The smallest detectable embolised artery measured 1.6 mm in diameter and was located in the 6th generation of the pulmonary vascular system.

CONCLUSIONS

In this experimental study MR angiography enhanced by a macromolecular contrast agent allowed noninvasive diagnosis of pulmonary artery embolism.