The application study on DWI monoexponential and biexponential signal decay analysis in the diagnosis of hepatocellular carcinoma / 实用放射学杂志

ABSTRACT

Objective To evaluate mono-and bi-exponential decay models in the diagnosis of hepatocellular carcinoma (HCC). Methods 28 patients with HCC who underwent conventional MRI imaging and diffusion-weighted imaging were collected,and all the HCC lesions were proved by operation pathology.The ADC values in mono-exponential decay model and ADCst ,ADCslow , ADCfast and ffast of the lesions in bi-exponential decay model were measured through the reconstruction of ADCmap ,ADCslow map, ADCfast map and fraction of fast ADC at a workstation.The relationships between the ADC values with low,medium and high b-val-ues and different differentiation degrees of HCC were analyzed.Moreover,the relationships between the ADCst ,ADCslow ,ADCfast , ffast values and HCC defferentiation grades were also explored.Results Significant differences in ADC value were found among differ-ent degrees of HCC differentiation in middle and high b-value groups (P <0.05).A positive correlation was found between the ADC value and the degree of HCC differentiation in middle (r=0.377,P <0.01)and high b-value group (r =0.81 5,P <0.01).There were no significant differences in ADC value among the different degrees of HCC differentiation in low b-value group.There were significant differences in the values of ADCst ,ADCslow and ADCfast among different degrees of HCC differentiation.Significant posi-tive correlations were found between the values of ADCst ,ADCslow and ADCfast and the degree of differentiation (P <0.01).There were no significant differences in the values of ffast among different degrees of HCC differentiation.Conclusion ADC value in mono-exponential decay model plays a potential role in the diagnosis of different differentiation degree of HCC with a b value ≥400 s/mm2 .Furthermore,the parameters in bi-exponential decay model,especially the values of ADCst ,ADCslow and ADCfast ,can provide new and unique information in the distinction of different degrees of HCC differentiation.