Gd-EOB-DTPA Enhanced MRI T₁ Mapping Combined With Standard Liver Volume Ratio For Estimation Of Liver Function

Objective:To explore the application value of Gd-EOB-DTPA enhanced MRI T₁ mapping combined with standard liver volume ratio?LV/SLV?for estimation of liver function.Methods:80 patients underwent Gd-EOB-DTPA enhanced MRI T₁ mapping were prospectively enrolled.Variable flip angles T₁ mapping sequences were performed before and after 20 minutes?hepatobiliary phase,HBP?with Gd-EOB-DTPA injection.Clinic data of patients were collected and were used to classify different groups.Patients were divided into three groups according to Child-Pugh score as follows:NLF?normal liver function??n=26?,LCA?Liver cirrhosis with Child-Pugh A??n=30?,LCB+LCC?Liver cirrhosis with Child-Pugh B+C??n=24?,and divided into two groups according to MELD:good liver function?MELD?8??n=57?and poor liver function?MELD?9??n=23?.All the MRI data were transferred to the Siemens Syngo workstation.The T₁ relaxation times were measured by using operator-defined regions of interest?ROIs?.Five ROIs with 0.35cm² area was drawn on portal hepatic level of the T₁ maps.The average T₁ value on pre-contrast and HBP were respectively recorded as T_{1 pre},T_{1 post},and then reduction rate of T₁ relaxation time[?T₁,?T₁=(T_1pre-T_1post)/T_1pre×100%]was calculated.The liver volumes?LV?were measured on HBP imagings.The body surface areas?BSA?were calculated with the heights and weights of patients according to the following formula:BSA?m²?=weight?kg?^0.425×height?cm?^0.725×0.007184,and standard liver volumes?SLV?were calculated as follows:SLV?ml?=706.2×BSA?m²?+2.4.The liver volume to standard liver volume ratio?LV/SLV?was calculated.The one-way ANOVA was used to compared the indexes(T_1post,T_1post×LV/SLV,?T₁,?T₁×LV/SLV)in different liver function groups of NLF,LCA,LCB+LCC.The t-test was used to compared the indexes(T_1post,T_1post×LV/SLV,?T₁,?T₁×LV/SLV)in MELD?8 and MELD?9 groups.Spearman correlation analysis was applied to analyze the correlation of all indexes with Child-Pugh and MELD system.Receiver operator characteristic curves?ROC?were drawn and compared the area under the curve of all indexes to compare the diagnostic performance of T_1post,T_1post×LV/SLV,?T₁,?T₁×LV/SLV.Results:All groups showed the significant difference among T_1post,T_1post×LV/SLV,?T₁,?T₁×LV/SLV?P<0.05?.The AUCs of?T₁×LV/SLV in the MELD?8 and MELD?9?0.902?,NLF and LCA?0.771?,NLF and LCB+LCC?1.000?,LCA and LCB+LCC?0.924?were slightly higher than that of?T₁?0.886,0.764,0.992,0.904,respectively?.The T_1post?AUC 0.824?and T_1post×LV/SLV?AUC 0.789?showed a significant better than others indexes between the MELD groups.For the Child-Pugh groups,the AUCs of T_1post and T_1post×LV/SLV were0.713 and 0.687?between NLF and LCA?,0.987 and 0.973?between NLF and LCB+LCC?,0.915 and 0.871?between LCA and LCB+LCC?,respectively.The T_1post×LV/SLV showed a slightly lower AUCs among the different liver function groups than T_1post.Conclusion:1.The results of T_1post and?T₁ based on Gd-EOB-DTPA enhanced MRI to estimate liver function were consistent with Child-Pugh and MELD scores.T_1post and?T₁showed a useful value to assess liver function.2.?T₁×LV/SLV was more accurate for estimation of liver function.