Our purpose was to investigate the usefulness of Lipiodol-CT for detection of residual viable neoplastic tissue in hepatocellular carcinoma (HCC) lesions treated by means of percutaneous ethanol injection (PEI). An emulsion of 5 to 20 ml iodized oil and 50 to 70 mg doxorubicin hydrochloride was intraarterially injected in 18 patients with 25 HCC lesions treated by means of PEI one to 24 months before. At CT performed 3 to 5 weeks after injection, retention of Lipiodol was observed in 9 of 13 tumors that still contained viable neoplastic tissue and in 2 of 12 tumors proven to have undergone complete necrosis after PEI. The sensitivity and specificity of Lipiodol-CT were 69.2% and 83.3%, respectively. Thus, Lipiodol-CT seems to have limited diagnostic value after PEI, probably as a consequence of the alcohol-induced vascular damage, accounting for both false-negative and false-positive results.