Abstract: Objective To study the application value of quantitative assessment of iodine concentration by computed tomography (CT) energy spectrum imaging in the differential diagnosis of hepatocellular carcinoma (HCC) and hypervascular hepatic metastases (HVHM). Methods A total of 141 patients with malignant liver tumors admitted to our hospital from August 2015 to August 2019 were enrolled. They were divided into group A (HVHM, 60 cases) and group B (HCC, 81 cases) according to pathological types. All patients underwent spectral CT scanning. The normalized iodine (water) concentration in arterial phase and portal phase, the ratio of iodine concentration between lesions and normal liver tissue, water (iodine) concentration, slope of energy spectral curve and iodine concentration difference between venous and arterial phase were compared between the 2 groups. And the efficacy of the quantitative parameters above in differential diagnosis of HCC and HVHM was analyzed. Results The values of normalized iodine (water) concentration, the ratio of iodine concentration between lesions and normal liver tissue, and the slope of energy spectral curve in group A were significantly higher than those in group B (P<0.05). The normalized iodine (water) concentration value in the portal phase, the ratio of iodine concentration between the lesions and normal liver tissue in the portal phase, and the slope of the energy spectral curve in the portal phase were all effective in the differential diagnosis of HCC and HVHM, and the area under the curve was 0.746, 0.778 and 0.802, respectively. Conclusion There are significant differences in quantitative parameters of spectral CT imaging, which provides an important reference for the differential diagnosis of HCC and HVHM.

Key words: Computed tomography energy spectrum imaging, Hepatocellular carcinoma, Hypervascular liver metastases