摘要Objective: To investigate the imaging features and clinical significance of carbon dioxide digital subtraction angiography (CO2-DSA) in the diagnosis and treatment of hepatocellular carcinoma (HCC).Methods: Both CO2-DSA and conventional DSA were performed in all 47 patients with HCC, and the angiographic manifestations of CO2-DSA were compared with those of conventional DSA in the same patients.Results: Peripheral arterial and capillary imaging by CO2-DSA was inferior to that by conventional DSA, although blood pools were well visualized with CO2. Improved visualization of arterioportal shunting (APS)was obtained with CO2-DSA compared with that by conventional angiography. APS was observed in 33 cases by CO2-DSA and in 12 cases by conventional angiography (P＜0. 001). Retrograde visualization of the portal vein (PV) trunk and its large branches was demonstrated in 16 cases by CO2-DSA and in 1 case by conventional DSA (P＜0. 001). The manifestation of lipiodol retention in the tumors was consistent with CO2-DSA images after TAE in 38 cases, and with those of conventional DSA in 23 cases (P＜0. 01). Conclusion: CO2-DSA was superior to conventional DSA in the detection of APS and retrograde visualization of PV system,and the former can provide usefulness information for the treatment planning (chemoembolization) and patient prognosis. Demonstration of APS by CO2-DSA may suggest the presence of intrahepatic metastases.