[CO2US via an implantable port--drug distribution in intraarterial chemotherapy for hepatic tumors and evaluation of effect].

The distribution of blood flow was determined from the distribution of CO2 by US performed during the infusion of CO2 microbubbles via an implantable port (IP-CO2US) in intraarterial chemotherapy for hepatic tumor, and the usefulness of this method in determining tumor vascularity and evaluating the effects of therapy was investigated. A total of 16 patients, 12 of whom had metastatic liver tumor, two hepatocellular carcinoma, one gall bladder carcinoma, and one cholangiocellular carcinoma were studied. The enhanced areas in the liver in 16 patients in whom IP-CO2US was performed a total of 24 times were consistent in all cases with the enhanced areas demonstrated by IP-RI angiography performed a total of 10 times within 10 days, and were also consistent with one exception with the enhanced areas demonstrated by IP-CTA performed 14 times. The tumor detection rate was markedly higher with IP-CO2US than with plain US or IP-DSA, and was similar to that of IP-CTA. Evaluation of the vascularity of individual nodules by IP-CO2US surpassed that by IP-DSA, and was similar to that of IP-CTA. It was demonstrated that blood flow distribution (intrahepatic drug distribution) can be equally well grasped with IP-CO2US, which is a simple and convenient method, as with IP-RI angiography. It was also suggested that IP-CO2US is useful in the evaluation of tumor vascularity and the effect of therapy.