Evaluation of hypervascular hepatocellular carcinoma in cirrhotic liver: Comparison of different concentrations of contrast material with multi-detector row helical CT – A prospective randomized study

PurposeTo evaluate two different iodine concentrations of contrast material for detecting hypervascular hepatocellular carcinomas (HCCs) in cirrhotic liver by multi-detector row helical CT (MDCT) when a fixed contrast material volume and injection rate is used.Materials and methodsInstitutional Review Board approval was obtained, and informed consent was obtained from all patients. In this prospective study, 105 patients were randomly assigned a group A (an iodine concentration of 300 mg I/mL), and a group B (an iodine concentration of 370 mg I/mL). In both groups the volume of contrast material was 100 mL and the injection rate was 4 mL/s. Fifty-two patients had 122 hypervascular HCCs. The diagnosis of HCCs was established histopathologically (n = 24) and by imaging findings (n = 98). Three readers independently analyzed four image sets: an arterial phase (AP), a portal phase (PP), an equilibrium phase (EP), and combined all three phase images set. Sensitivity, specificity, and diagnostic accuracy were calculated by receiver operating characteristic (ROC) analysis.ResultsThe mean sensitivity for detecting hypervascular HCCs of the AP set, EP set, and combination set in group B (0.94, 0.81, and 0.93) was significantly higher than in group A (0.84, 0.69, and 0.80). Area under the ROC curve of the AP set and the combination set in group B (0.974 and 0.981) was significantly higher than in group A (0.939 and 0.958).ConclusionAt the same contrast material volume and injection rate, higher iodine concentration of contrast material was effective for detecting hypervascular HCCs by MDCT.