CT Features Analysis Of Alveolar Echinococcosis With Extrahepatic Metastasis

Objective: To explore the difference of the general condition and the morphology of CT images of intrahepatic lesions between patients with alveolar echinococcosis with and without extrahepatic metastasis and to analyze the CT imaging characteristics of intrahepatic lesions of patients with alveolar echinococcosis with extrahepatic metastasis.Data and method: Totally 290 patients with alveolar echinococcosis diagnosed or confirmed by clinical diagnosis and imaging in Affiliated Hospital of Qinghai University from January 2015 to September 2019 were collected.Based on the examination result and the clinical diagnosis result,the 290 patients were divided into extrahepatic metastasis group and non-extrahepatic metastasis group,with 124 patients and 166 patients respectively.The age and gender differences between the two groups were analyzed.The types,calcification morphology,maximum diameter,location,range and number of intrahepatic lesions,invasion of hepatic veins,portal veins,intrahepatic and intrahepatic bile ducts,peripheral organs or tissues of the liver,and the amount of ascites quantity in the two groups were analyzed based on CT images.In addition,laboratory test results at the first diagnosis of the two groups were collected and the differences were analyzed,involving echinococcosis antibody test(ELISA),total bilirubin(TB),serum albumin(ALB),prothrombin time(PT),hepatitis b virus surface antigen test(HBsAg),and liver function Child-Pugh grading.The data obtained were imported into SPSS24.0 for statistical analysis.Results: Among the 125 patients in extrahepatic metastasis group,there were 58 patients(46.8%)with single pulmonary metastasis,21 patients(16.9%)with single brain metastasis,9 patients(7.3%)with single site metastasis in other organs except for lung and brain(such as spine,retroperitoneal lymph node,ribs,etc.),and 36 patients(29.0%)with metastasis in two or more sites.The non-extrahepatic metastasis group included 166 patients.The differences in the mean maximum diameter of intrahepatic lesions,the positive rate of invasion of liver segments 1,2,4,5,6,7 and 8,the positive rate of invasion of three or more hepatic segments,the positive rate of two or more intrahepatic lesions,and the positive rate of invasion of peripheral organs or tissues of the liver between the two groups were statistically significant(P〈0.05);The differences of positive rates of invasion of right hepatic vein,middle hepatic vein,inferior vena cava,inter-portion of postcava,right branch of portal vein,portal trunk,right intrahepatic bile duct,left intrahepatic bile duct and common hepatic bile duct caused by lesions were statistically significant(P〈0.05).In addition,differences in age,Child-Pugh grading of liver function and ALB content between the two groups were statistically significant(P〈0.05).Differences in other imaging signs and laboratory indicators between the two groups were not statistically significant.Conclusion: Compared with patients with alveolar echinococcosis in non-extrahepatic metastasis group,the patients in extrahepatic metastasis group had more intrahepatic lesions that invade the right lobe and caudate lobe of the liver,and they had more intrahepatic lesions in liver,that the lesions with larger diameter,so that more severe lesions that invade vessels,bile ducts,or other adjacent tissues inside and outside the liver.These imaging signs are helpful in early warning of the possibility of extrahepatic metastasis of HAE in the liver.