PURPOSE: To evaluate the usefulness of epinephrine infusion (Pharmaco-CTHA) prior to liver to liver spiral CT during hepatic arteriography in patients with hepatocellular carcinoma. MATERIALS AND METHODS: Twenty-two patients in whom hepatocellular carcinoma had been diagnosed underwent three types of liver spiral CT during hepatic arteriography. In the first method, spiral CT scanning was started 5 seconds after injecting 8cc of contrast media at a rate of 0.3cc/sec. In the second, 10 microgram of epinephrine was slowly injected for 1 minute via the catheter and subsequent spiral CT scanning began 11 seconds after injecting 8cc of contrast media at a rate of 0.3cc/sec. In the third method, spiral CT scanning was started 5 seconds after injecting 25cc of contrast media at a rate of 1cc/sec. The following were evaluated and compared with the results of follow-up lipiodol CT: 1) the incidence of false positive lesions; 2) the incidence of false negative lesions; 3) portal enhancement; and 4) lesion conspicuity. RESULTS: Follow-up lipiodol CT of 22 patients showed 16 masses. In 12 patients there was no lipiodol uptake, and in five, four and one patient(s), uptake occurred once, twice, and three times, respectively. With method 1there were nine false-positive lesions, with method 2 there were 13, and with method 3, there were 49. The use of method 2(Pharmaco-CTNA) led to less false-positives than did method 3 (conventional CTHA)(p=0.000). Method 1 showed the lowest false positive rate (nine lesions), but its false-negative rate was two and four times higher than with method 2 (four lesions) and with method 3 (two lesions), respectively. Portal enhancement was observed four times using method 3 and once with method 1, but was absent with method 2. As regards the conspicuity of 16 masses, "good" and "excellent" lesions were seen four times with method 1(25%), ten times with method 2 (62.5%) and thirteen times with method 3 (81.3%). CONCLUSION: The infusion of epinephrine (Pharmaco-CTHA) prior to spiral CT during hepatic arteriography has the advantage of reducing the amount of contrast media required as well as the number of cases which are false positive and show no portal enhancement.