Clinical Evaluation Of Liver-specific Mr Contrast Agents

Objective To evaluate the application value of liver-specific contrast agents in the analysis for the liver tumors and the evaluation of liver function.Materials and Methods36patients who were suspected to be with liver tumor by Clinical diagnosis or Ultrasound diagnosis went thought MRI examination.27cases were confirmed by surgery or pathology,6cases were confirmed by comprehensive diagnosis with clinical imagings,3cases were excluded because of diffuse nodulars. All cases are used with liver-specific contrast agent (Gd-BOPTA28cases,Gd-EOB-DTPA12cases)MR conventional multi phase enhanced scan, including arterial phase (20s), portal venous phase (50s),equilibrium phase (120s) and hepatobiliary phase, hepatobiliary excretion phase. The scanning time of hepatobiliary phase and hepatobiliary excretion phase with Gd-BOPTA and Gd-EOB-DTPA were40min、120min and20min、60min.Two Senior doctor who were experted in the MR diagnosis of liver diseases successively observed conventional MRI group (plain+three phase dynamic enhanced scan) image and combined-MRI (plain+three phase dynamic enhanced scanning+hepatobiliary phase) image separately. The detection rate, sensitivity, specificity and accuracy of the two image groups were calculated and compared. Measure the signal intensity of the cancerous lesions and the noncancerous lesions in hepatobiliary phase,compared their signal intensity ratio with the muscle. The liver function of all cases were evaluated wih the biliary display in the hepatobiliary excretion phase. The biliary display in the hepatobiliary excretion phase were evaluated with a five score Category.0point represents the biliary is not shown;1point represents the biliary shows fuzzy;2points represent between1and3point;3points represent the biliary is shown poorly, but it does not affect the diagnosis.4points represent the biliary is clear.According to total score of patients’bile duct, Patients’liver function is graded:0-5points are graded for C,6～15points B,>16A. To analysis the consistency of liver-specific contrast agent enhanced hepatobiliary phase image liver function grading and clinical classification of Child-pugh. Measure the signal intensity of the liver parenchyma on Siemens MR processing software in the hepatobiliary excretion phase.The mean signal intensity of liver parenchyma with different level liver function are compared.Data is analysised with SSPS13.0.Measurement Data is shown with mean±SD (X±S); The independent Student’s t test was used to compare the Measurement Data. Statistical differences were determined by R X C Chi-square test to compare Enumeration Data, but when Theoretical Frequency of1/5lattice is more than1and less than5or when theoretical frequency of1lattice is less than l,the Fisher’s exact test will be used. Again, a P-value v0.05was considered to indicate a statistically significant difference.The consistency of the two doctors’judgment and the evaluatation with the image grading and clinical Child-pugh grading for liver function are checked with clinical consistence Kappa test:if the K value is less than0.4, the consistence shows poor,if higher than0.4but less than0.7, the consistence shows OK,if higher than0.7,high. Results33patients with55lesions were included in our study,all the lesions were found in the MRI examination.22patients with35lesions were identified to be HCC,in which there were14lesions showed wash-out in the conventional enhanced scanning,the others were not.All the HCC showed hypodense in the hepatobiliary phase;4patients with8lesions were identified to be DN,2patients with3lesions RN,4patients with4lesions Hepatic Hemangioma,4patients with4lesions4Inflammatory,1patients with1lesions FNH.All the lesions showed atypical manifestation in the conventional MR scanning,and in the hepatobiliary phase they all showed isodense’or hypodense except the1Hepatic Hemangioma hyperdense.The detection rate of The conventional MRI scanning (plain+three phase dynamic enhanced scan) image group and combining MRI scanning (plain+three phase dynamic enhanced scan+hepatobiliary phase) image group were respectively87.3%、99.1%according to the two doctors,and the difference between the two image groups shows significantly (P<0.005).The sensitivity, specificity and accuracy of the conventional MRI (plain+three phase dynamic enhanced scan) image group were94.6%/92.3%.65.2%/66.7%,83.3%/83.3%according to the two doctors,and of combining MRI ((plain+three phase dynamic enhanced scan+hepatobiliary phase) image group95.5%/93.3%、93.8%/93.3%.95.0%/93.3%. The sensitivity, specificity and accuracy of the conventional MRI (plain+three phase dynamic enhanced scan) image group were higher than that of combining MRI ((plain+three phase dynamic enhanced scan+hepatobiliary phase) image group,but there were no statistically significant between this two groups. The signal intensity ratio of the cancerous lesions with the muscle in hepatobiliary phase were0.94±0.04, and the noncancerous lesions1.04±0.19, the difference between the two shows significantly (P<0.005) According to the visibility score of biliary in the hepatobiliary excretion phase images,33patients’liver function can be classified as A grade (grade>16points)17cases, B (6to15points)10cases, C (6to15points)6cases. The consistency of the evaluatation with the image grading and clinical Child-pugh grading for liver function were OK in the33patients (k=0.570, P=0.000), therein,it was excellent particularly in the10cases with Gd-EOB-DTPA enhanced (k=0.804, P=0.000). The signal intensity of the liver parenchyma with different level liver function in the hepatobiliary excretion phase were different(P<0.005),the highest were that with liver function Child-Pugh A.Conclusion1. The Liver-specific contrast agent can improve the signal of liver parenchyma as a result to improve the detection ratio of liver lesions.2. The MR enhanced scanning with Liver-specific contrast agent can increase the diagnostic information for HCC, so that our confidence to diagnose HCC rises.3.The use of the Liver-specific contrast agent can not only examine the liver lesion but also evaluate the liver function,which were called "One-stop" check.