[Echo-color Doppler in the study of portal hypertension]

Color-Doppler US is currently an extremely valuable tool in the study of abdominal circulation, cirrhosis of liver and its complications, different kinds of portal hypertension, vascular/avascular liver malformations and, finally, in the evaluation of liver transplants. Moreover, its use in experimental studies has yielded good results. Even spontaneous porto-systemic shunts can be demonstrated in most cases (up to 88%). Color-Doppler allows partial obstructions to be demonstrated and permits qualitative and quantitative dynamic evaluations the presence/absence of flow, vascular masses--e.g., mean velocity measurement and blood flow assessment. The interobserver variability of the method was calculated with a double-blind study carried out by our laboratory team cooperating with a study group from the University of Yale, USA. The study evidenced how color-Doppler US cannot be used to follow the single patient unless the variations to measure are higher than variability itself. Color-Doppler limitations depend on the subjectivity of the results and on its difficult application to obese patients or to those with severe intestinal meteorism.