ABSTRACT
Purpose To investigate the value of T2WI mild-moderate signal and restricted diffusion in the context of liver imaging reporting and data system (LI-RADS) (2014 edition) in the diagnosis of hepatocellular carcinoma (HCC) with cirrhosis caused by hepatitis B virus.Materials and Methods A total of 77 lesions (LI-RADS 3-5,size of 1.1 cm×0.7 cm-12.7 cm×9.1 cm) of 69 HCC patients in Beijing Friendship Hospital from January 2012 to November 2016 were retrospectively analyzed.All these patients underwent MRI scan and multiphase dynamic enhanced scan.The images were analyzed by two radiologists.If a disagreement occurred,liver accelerated volume acquisition and multiphase dynamic enhanced scan were combined to reach a consensus.The contrast noise ratio (CNR) and apparent diffusion coefficient (ADC) of T2WI and diffusion weighted imaging (DWI) sequences were compared,as well as the identification of the two signs.Results There was no statistically significant difference between T2WI mild-moderate signal and restricted diffusion in the identification of lesions (LI-RADS 3-5) (P＞0.05),while the sensitivity with DWI b=0 (61.0％) was significantly lower than DWI b=600 s/mm2 (70.1％) (P＜0.05).The CNR of all DWI sequences (b=0,600 s/mm2) were larger than those of T2WI (P＜0.01).The ADC of small lesions (diameter ＜2 cm) were larger than those of larger lesions (diameter ＞2 cm) [(1.57+0.37)×10-3 mm2/s vs.(1.37+0.51)×10 3 mm2/s,P＜0.05].Conclusion There is no significant difference in sensitivity of lesions between T2WI mild-moderate signal and restricted diffusion.However,due to different CNRs,DWI with b=600 s/mm2 is more obvious for the lesions,and can be first investigated in practice.