Fig. 9. Malignant thrombosis of the portal vein.

A. Pre-contrast spectral Doppler analysis shows only venous pattern (portal) flow in the thrombosed segment of the portal vein. B. After contrast-enhanced ultrasonography, the spectral Doppler analysis shows intra-thrombus arterial flow. Microbubble agents render intra-thrombus blood flow more evident in both spectral and color Doppler modes. C. It is possible to observe a flow pattern in the common hepatic artery. Note that the pattern seen in the hepatic artery is quite different (high resistivity) from that of the tumoral thrombus (lower resistivity). When we find arterial flow in a vein, we can close the diagnosis of tumor thrombosis or "tumor in vein."PSV, peak systolic velocity; EDV, end-diastolic velocity; RI, resistive index.