How are Doppler waveforms altered in PV thrombosis?
In acute PV thrombosis, flow in the PV is markedly diminished or absent, with no Doppler waveform or color flow. Cavernous transformation of the PV, manifested by multiple tubular channels in the porta hepatis demonstrating Doppler and color flow with nonvisualization of the native PV, may develop within 12 months. Echogenic material representing thrombus is usually seen in the PV. An arterial waveform within the thrombus is highly specific for malignancy.