The variable CT appearance of hepatic abscesses.

Fifty computed tomographic (CT) scans in 33 patients with 37 separate episodes of hepatic abscess were reviewed retrospectively. Abnormalities were detected in all but one case (97% sensitivity). However, a characteristic CT appearance of hepatic abscess was not evident. Most intrahepatic foci were solitary, but multiple abscesses were present in 34% of cases. The CT appearance of the lesions varied from well defined, rounded cavities with contents near water density, resembling poorly defined hepatic cysts, to higher-density foci indistinguishable from hepatic neoplasms. In only 19% was gas present within the abscess. Rim enhancement was seen in only 6%. This study suggests that CT is a sensitive test for detecting hepatic abscess but is often nonspecific.