Afferent and efferent vessels of premalignant and overt hepatocellular carcinoma: observation by color Doppler imaging.

Afferent and efferent vessels of premalignant and overt hepatocellular carcinoma (HCC) were analyzed using color Doppler imaging. With afferent blood flow, constant waveform signals reflecting portal inflow are a characteristic finding in dysplastic nodules and early well-differentiated HCC. Among advanced HCCs lacking portal blood flow, inflow of arterial pulsatile blood flow signals is characteristic for advanced HCC with increased arterial vascularity. Efferent blood flow enters the hepatic vein of the lowest pressure system in dysplastic nodules and early well-differentiated HCC with afferent portal blood flow. Analysis of waveforms of efferent blood flow signals in advanced HCC detects in the opposite direction adjacent to an accompanying afferent arterial pulsatile blood flow signal. In conclusion, during multistep human hepatocarcinogenesis hemodynamics show characteristic changes; the state of afferent portal blood with low arterial vascularity loses the portal blood flow, and arterial vascularity gradually increases. The efferent blood flow pathway also changes with the pathological multistep development process.