Artifact reduction in bolus-enhanced spiral CT of pulmonary arteries usinga saline push.

Purpose: To improve the diagnostic efficacy of bolus-enhanced spiral CT (SC T) in the detection of pulmonary embolism using a saline push immediately a fter bolus injection of the contrast medium. Patients and Methods: The stud y included 90 patients with suspected acute or chronic pulmonary embolism. The CT scan was performed in a caudocephaled direction. In Group 1 (n=60) w e applied a bolus contrast injection (120 ml, 3 ml/s, 300 mg J/ml), after a median delay of 25 s. Group H (n=30) had the same contrast injection which was immediately followed by an additional saline push (60 ml, 2 ml/s). Str eak artifacts originating from high contrast concentrations in the superior vena cava were rated on a 1-point scale for different locations: right pul monary artery, pars basalis, truncus anterior, and the segmental upper robe arteries. Results: The incidence of artifacts in group I was nearly twice as high as in group II. The difference was significant (p <0.05) for the up per and anterior superior robe artery, the Fight pulmonary artery and the p ars basalis. Conclusion: The presented protocol significantly reduces artif acts mainly by a washout of contrast medium in the superior vena cava.