Contrast enhanced power Doppler sonography: Comparison of different administration forms of the ultrasound contrast agent Levovist (R)

Purpose: Objective of the present study was the comparison of various admin istration forms of the ultrasound contrast medium Levovist(R) with regard t o duration and intensity of contrast enhancement in patients with tumors of the liver or pancreas. Patients and Methods: Seven patients with tumors of the liver or pancreas were examined prospectively using power Doppler sono graphy. Ultrasound contrast enhancement was achieved using Levovist(R) (8 m l, 400 mg/ml) in three different administration forms: 1(st) as a bolus inj ection through the main channel, 2(nd) through the injection valve of an in travenous cannula, or 3(rd) as a continuous infusion. Semiquantitative eval uation of the degree of contrast enhancement over the course of the examina tion was conducted by three independent examiners. Results: Levovist(R), ad ministered by continuous infusion, resulted in a significantly longer avera ge period of contrast enhancement (9:43 min (extratumoral), 7:34 min (intra tumoral)) than did the same dosage administered as a bolus injection throug h the main channel (6:01 min (extratumoral), 4:54 min (intratumoral), p = 0 .0156 (extratumoral); p = 0.0313 (intratumoral), but contrast intensity was decreased. Bolus injection through the injection valve of the i.v. cannula was associated with decreased duration and intensity of contrast enhanceme nt compared with injection through the main channel. Conclusion: Compared w ith bolus injection, the continuous infusion of Levovist(R) resulted in a s ignificant prolongation of the duration but in a decreased intensity of con trast enhancement. Administration of Levovist(R) through the injection valv e does not result in optimal contrast enhancement and is therefore not reco mmended.