Diagnosis of portal vein tumor thrombus by pulsed Doppler ultrasonography.

The blood flow of portal vein thrombus was studied by pulsed Doppler ultrasonography in 21 patients with tumor thrombus and 14 with blood clot thrombus. Pulsatile waves were observed in 19 of the 21 with tumor thrombus, with backward continuous waves in 3, and forward/backward continuous waves in 2. In contrast, forward continuous waves were observed in 2 of the 14 with blood clot thrombus. By color imaging, the blood flow could be observed in 9 of 14 with tumor thrombus, but in 1 of 7 with blood clot thrombus. Pulsatile and backward continuous waves were characteristic of tumor thrombus.