Clinical Study On Evaluation Of Hepatic Reserve By Gd-EOB-DTPA-enhanced MRI Combined With Liver Volume

Objective: To investigate the value of liver volume and gadolinium-ethoxybenzyl-diethylen-etriamine pentaacetic acid(Gd-EOB-DTPA)enhanced magnetic resonance imaging(MRI)applying in the evaluation of hepatic reserve,and construct a new calculating equation by combining liver volume(LV)with Gd-EOB-DTPA-enhanced liver MRI,with its significance determined by comparing with previous single-parameter studies.Methods : The clinical and imaging data of 42 patients with hepatic focal lesions were retrospectively analyzed.All patients received Gd-EOB-DTPA-enhanced MRI,Child-Pugh scoring and ICG clearance test.The patients were classified into 2 groups according to Child-Pugh classification: liver cirrhosis with Child-Pugh A group(LCA group,n = 25)and liver cirrhosis with Child-Pugh B group(LCB group,n = 17).Signal intensity(SI)was measured in regions of interest(ROI)with an area of about 100 ± 5 mm2 of the left lateral lobe,left intrahepatic lobe,right anterior lobe and right posterior lobe in Gd-EOB-DTPA-enhanced MRI pre-scanning images and hepatobiliary phase MRI images at the hepatic portal level,with ROI position and size maintained consistent in the pre-and post-phase.The relative of enhancement of the liver(RE)is calculated by the following formula: RE =(SIpost-SIpre)/SIpre,where SIpre indicates mean SI in pre-scanning and SIpost indicates mean SI in hepatobiliary phase.Using the image post-processing workstation(GE ADW 4.5),the outline of the liver in the hepatobiliary phase was drawn layer by layer,and the three-dimensional image of the liver and LV were reconstruct by computer.Before examination,height and body weight were collected from each patient to calculate body surface area(BSA),with BSA(m2)= body weight(kg)0.425 × height(cm)0.725 × 0.007184.Then,standard liver volume(SLV)was calculated as follows: SLV(ml)= 706.2 × BSA(m2)+ 2.4.ICG retention rate at 15 min(ICG-R15),prothrombin time(PT),total bilirubin(T-BIL),albumin(ALB),LV and RE were compared between the LCA group and the LCB group,with data conforming normal distribution analyzed by student’s t-test for independent samples and data does not conform to normal distribution analyzed by nonparametric test for 2 independent samples.The correlations of RE with ICG-R15,LV,PT,T-BIL and ALB,and of ICG-R15 with LV,LV/SLV,RE,RE × LV and RE × LV/SLV were analyzed,with data obeying normal distribution analyzed by Pearson correlation analysis and data disobeying normal distribution analyzed by Spearman correlation analysis.Results: ICG-R15 did not obey normal distribution and was analyzed by nonparametric test for 2 independent samples.No significant differences were detected in PT or LV between the LCA group and the LCB group(P > 0.05),while ICG-R15,T-BIL,ALB and RE were statistically significant(P < 0.05).ICG-R15 did not obey normal distribution and was analyzed by Spearman correlation analysis.RE was negatively correlated with ICG-R15(correlation coefficient,-0.447;P > 0.05).RE showed no significant correlations with LV,LV/SLV.ICG-R15 was negatively correlated with RE(r =-0.447,P = 0.003),RE × LV/SLV(r =-0.524,P = 0.000).Conclusions: 1.In the evaluation of hepatic reserve,RE is superior to LV,and signal changes in hepatobiliary phase can reflect the changes of liver reserve more sensitively;ICG-R15 is correlated with RE.2.The combination of RE and LV is a valuable method for evaluating hepatic reserve.The value of using SLV to eliminate individual differences in the study of LV is worth paying attention to.