The Research On The Influence Of Hepatic Background In Diagnosing Hepatic Focal Nodules Using Contrast-enchanced Ultrasound

Objective: To probe the influence of hepatic background in diagnosing hepatic focal nodules using Contrast-enhancement ultrasound through clinical and animal experiment.Methods:Animal study:45 male New Zealand rabbits are grouped into A,B,C group. A group was control group ,the rabbits were fed with normal feedstuffs for 12 weeks, B group were fed with high-lipid feedstuffs for 4 weeks and used for fatty liver model, C group were fed with high-lipid feedstuffs for 12 weeks and used for liver cirrhosis model. Two-dimensional ultrasound and CEUS were performed after the model were built. Liver specimen were examined histologically. Analyze the entire CEUS duration using time-intensity curve(TIC) software. Both the starting enhancement time and the lasting enhancement time of different hepatic background were compared.Clinical study:174 patients with hepatic focal lesions underwent CEUS were admitted and classified into four categories on the basis of hepatic background.The first group was normal hepatic background(I group),containing 63 cases.The second group was compensatory cirrhosis background (II group), containing 28 cases.The third group was decompensated cirrhosis background (III group),containing 43 cases.The last group was fatty liver background(IV group),containing 41 cases.Among 89 cases with hepatocellular carcinoma,I group contained 26 cases,II group contained 28 cases, III group contained 35 cases. Among 46 cases with hemangioma, I group contained 25 cases ,IV group contained 21 cases. Among 23 cases with focal nodular hyperplasia, I group contained 12 cases , IV group contained 11 cases. 8 cases of regenerative nodules belong to III group ,8 cases of focal fatty sparing belong to IV group .Both the starting enhancement time and the lasting enhancement time of different hepatic background were compared. The perfusion, the echo diversification and the enhancement mode of hepatic lesions in different hepatic background were compared.ResultsAnimal study results The pathology examination manifest that the fatty liver model and liver cirrhosis model were successfully built.Two-dimensional ultrasound showed characteristic ultrasonic changes.The starting enhancement time of the liver parenchymal of B,C group were obviously longer than that of A group (P<0.05).The peak intensity half-reduce time of B group is the longest and that of C group is the shortest.Clinical study results The starting enhancement time of II group, III group and IV group are longer than that of I group (p<0.05) ,among which IV group is the longest. The lasting enhancement time of I group had no statistical difference with that of II group. III group's lasting enhancement time was the shortest, IV group's lasting enhancement time was the longest among the four groups.84.6%(22/26) hepatocellular carcinomas with normal hepatic background and 92.9%(26/28)hepatocellular carcinomas with compensatory hepatic cirrhosis background displayed rapid enhancement in the artery phase ,showed hyperechoic or hypoechoic enhancement in the portal vein phase ,appeared hypoechoic enhancement in the delayed phase ,presented"fast-in and fast-out"enhancement mode. However, 15.4%(4/26) hepatocellular carcinomas with normal hepatic background and 7.1%(2/28)hepatocellular carcinomas with compensatory hepatic cirrhosis background appeared equivalent even hyperechoic enhancement in the delayed phase,presented"fast-in and slow-out"enhancement mode. Among 35 hepatocellular carcinomas with decompensated cirrhosis background , 85.8%(30/35) showed hyperechoic enhancement in the artery phase ,displayed equivalent enhancement in both the portal vein phase and the delayed phase , presented"fast-in and slow-out"enhancement mode. While 14.2%(5/35) displayed hyperechoic enhancement in the artery phase ,appeared hypoechoic enhancement in both the portal vein phase and the delayed phase, presented"fast-in and fast-out"enhancement mode. 25 hepatic haemangiomas with normal hepatic background and 21 hepatic haemangiomas with fatty hepatic background enhanced in a pattern of ring and centripetal fill-in in the artery phase, displayed equivalent enhancement in the portal vein phase, while the former even presented hyperechoic enhancement in the delayed phase .However, the latter appeared hypoechoic enhancement in the delayed phase. 12 focal nodular hyperplasias(FNH) with normal hepatic background and 11 FNH with fatty hepatic background presented wheel-like or holistic enhancement in the artery phase ,showed equivalent enhancement in the portal vein phase, while the former manifested hyperechoic enhancement in the delayed phase , whereas the latter manifested hypoechoic enhancement in the terminal delayed phase. 8 cases of regenerative nodules in liver cirrhosis as well as 8 cases of focal fatty sparing of liver showed equivalent enhancement in all of phases ,similar to the enhancement of the hepatic background.Conclusion The experimental study and clinical study showed that different hepatic background have different CEUS phase changes. Clinical study also manifested that focal liver nodules in different background have different CEUS enhancement mode.Thus, different hepatic background CEUS phase changes can influence the CEUS enhanced mode of focal nodules. Therefore, in the process of diagnosing hepatic focal nodules using CEUS, not only the hepatic focal nodules'pathological and biological characteristic should be highly think of ,but also the hepatic background should be take into account.