Gallstones Liver tumor CT CT liver tumor after contrast enhacement ERCP PTC MRA PTC primary sclerosing cholangitis Liver abscess. Computerised tomography scan showing an air–fluid level and rim enhancement with intravenous contrast typical of a liver abscess. In the adjacent liver is a calcified hydatid cyst Hydatid liver cyst. Active hydatid disease usually produces a non-calcified liver cyst and, within the cyst, floating layers of the germinal membrane can be seen.