Twenty patients were examined with CT of the liver before, during, and 4 to 6 hours after i.v. administration of 60 g iodine (200 ml iohexol). The attenuation of normal liver parenchyma was measured. The mean attenuation of normal liver parenchyma on nonenhanced scanning was 62.6 HU and on delayed scanning 78.7 HU. It seems that iohexol is a suitable contrast medium for delayed scanning of the liver.