Values of spectral CT imaging in differential diagnosis of hepatic carcinoma and liver metastasis

YA NG Chuan-hong; YU De-xin; WA NG Lin-lin; WA NG Qing; MA Xiang-xing

Abstract：Objective To explore the differences of spectral CT multi‐parameter imaging in hepatic carcinoma and liver metastasis ,intrahepatic metastasis of hepatic carcinoma and liver metastasis .Methods Thirty‐one patients with hepatic tumors underwent gemstone spectral imaging (GSI) scans ,including 15 patients with hepatic carcinoma and 16 ones with liver metastases ,in order to obtain spectral serial images in triple contrast‐enhanced phases .The spectral parameters of the lesions ,aorta ,portal vein and inferior vena cava were measured .Then ,the normalized parameters including CT values in different energy 1evels (50~70) keV ,iodine (water) concentration ,water (iodine) concentration ,iron (water) concen‐tration ,effective atomic number (Eff‐Z) ,and the spectral curves and iodine concentration differences (ICD) between arte‐rial and the portal venous phases were calculated .The above measurement results were analyzed with two samples t test . Results The CT values of hepatic carcinoma in different energy levels were (142 .500 ± 29 .106) HU (50keV) ,(112 .010 ± 20 .864) HU (60keV) and (93 .727 ± 15 .331) HU (70keV) ,while ,the iodine concentrations were 17 .235 ± 5 .089 (100ug/ml) and Eff‐Z were 8 .594 ± 0 .266 ,which were significantly higher than those of liver metastasis .The CT value of intrahepatic metastasis of hepatic carcinoma in different energy levels (50~70) keV ,iodine (water) concentration ,iron (water) concentration ,water (iodine) concentration ,Eff‐Z ,and some normalized parameters including CT value in the different energy 1evels (50~70) keV ,iodine (water) concentration ,iron (water) concentration and effective atomic num‐ber (Eff‐Z) were significantly higher than those of liver metastasis ( P<0 .05) .Conclusion The spectral CT imaging pa‐rameters of hepatic carcinoma are different from those of liver metastasis .Gemstone spectral CT imaging provides an effec‐tive method for differentiating hepatic carcinoma ,its intrahepatic metastasis and liver metastasis .