Duplex Doppler Ultrasonography in Portal Hypertension

Portal hypertension is one of the major complications of chronic liver disease and cirrhosis. Noninvasive duplex Doppler ultrasound can be repeated in the follow-up of hemodynamics of the portal system. Doppler sonography can identify and localize the course and dynamic of blood flow. Ultrasound contrast agents are gas-filled microbubbles that can improve the flow with poor Doppler signal quality. The main portal vein flow velocity and volume can be measured using duplex sonography. In this article, a variety of assessments for portal hemodynamics, including portal vein pulsatility index, portal vein congestion index, hepatic artery resistance index, hepatic circulatory index, splenic arterial pulsatility index, hepatic perfusion index, intrahepatic circulatory time, hepatic vein waveform and hepatic vein transit time, are discussed. Color flow images of esophageal varices and para-esophageal veins can be generated by the newly developed electronic radial endoscopic Doppler ultrasonography. Pulse-inversion ultrasonography improves the detection of liver metastasis and reveals more lesions of smaller size than conventional ultrasonography.