INTRAHEPATIC VENOUS COLLATERALS

Background: The aim of this study was to reevaluate the causes and sit es of intrahepatic venous collaterals and to determine the role of col or Doppler sonography in the diagnosis of this relatively rare vascula r abnormality. Methods: Real-time color Doppler sonography was used to study 21 patients with intrahepatic venous collaterals. The cause, di stribution, and clinical manifestations of collaterals were determined , and Doppler waveforms obtained from the collaterals were also analyz ed. Results: First, the causes of intrahepatic venous collaterals were divided roughly into two groups according to the presence or absence of veno-occlusions. The former group included liver tumors (six cases) , primary Budd-Chiari syndrome (five cases), and metastatic adrenal tu mors invading the inferior vena cava (two cases). The latter group con sisted of diaphragmatic hernia (three cases), Osler-Weber-Rendu diseas e (two cases), and congestive liver (one case). The cause was not dete rmined in two cases. Second, venous collaterals were distributed throu ghout the entire liver in primary Budd-Chiari syndrome but localized i n the other cases. Third, Doppler waveforms of the collaterals were di vided into two patterns: flat flow and multiphasic flow, Flat flow pat tern was seen in patients with veno-occlusive diseases, and multiphasi c flow pattern was seen in patients without veno-occlusive disease. Co nclusion: The relationship between intrahepatic venous collaterals and veno-occlusive diseases has been emphasized in the literature, but th e results of our series showed that they occurred under a wide variety of conditions, even without veno-occlusive diseases, including diaphr agmatic hernia and Osler-Weber-Rendu disease. The analysis of the Dopp ler waveforms of the collaterals was useful in differentiating those d ue to veno-occlusive diseases and those not.