The Role Of Ultrasonography In The Assessment Of Peripheral Intrahepatic Cholangiocarcinoma

Part One:Gray Scale Sonography Characterization of Peripheral Intrahepatic CholangiocarcinomaObjetive:To investigate the gray scale sonography features of peripheral intrahepatic cholangiocarcinoma(ICC).Methods:Gray scale sonography manifestations of 64 ICC proved by surgery and biopsy were analyzed retrospectively. Toshiba SSA—240A,Medison SA—6000 and Toshiba SSA—340A ultrasound systems with 3.5MHz-5.0MHz transducer were used.Results:Snography shows ICC in most cases usually as a homogeneous hypoechoic mass with irregular and ill-defined borders.However,it shows diverse echo patterns and may be hypo-,iso-, or hyperechoic.In some cases it presents hyperechoic lines.Unlike hepatocellular carcinoma,liver cirrhosis is infrequently presented in ICC.Intrahepatic biliary stones and dilation of the intrahepatic bile ducts are ancillary findings of ICC.The location of the masses can be well defined in 62 cases(96.9%) by sonography.Malignant tumor in 43 patients(67.2%) were diagnosed.The accurate pathologic diagnosis was achieved only in 10 cases(15.6%) before surgery.Conclusion:ICC presents some characteristic features on sonogram but it also has diverse manifestations.It is hard to diagnose ICC before surgery with gray scale sonography.Part Two:Value of Color Doppler Sonography in the Diagnosis of Peripheral Intrahepatic CholangiocarcinomaObjetive:To investigate the value of color Doppler sonography in the diagnosis of peripheral intrahepatic cholangiocarcinoma(ICC).Methods:Color Doppler sonography manifestations of 83 ICC proved by surgery and biopsy were analyzed retrospectively.Technos DU6,Acuson—128XP/10—ART and HP 8500 color duplex systems with transducer(3.5MHz～5.0MHz) were used.The distribution of color Doppler signals within and around the tumor were noted and the resistance index(RI) was measured.Results:Color Doppler signals were detected in 75 cases(90.4%).RI was higher than 0.6 in 93.3%(70/75) cases.Though ICC presents variety of patterns of blood flow within and around the nodules,the majority of the ICC lesions show spot or line pattern around the tumor.Accurate histology diagnosis was achieved in 26 (31.3%) cases.Conclusion:Color Doppler sonography can be used to evaluate the blood supply of the tumor and provide clinically useful information about the direction and the parameters(such as velocity,RI) of the blood flow,as well as the infiltration of the vessles.Part Three:Contrast-enhanced real-time harmonic gray scale ultrasound findings of peripheral intrahepatic cholangiocarcinomaObjective:To characterize the contrast-enhanced real-time harmonic gray scale ultrasound(CEUS) findings of ICC and to access the usefulness of CEUS in the diagnosis of ICC.Methods:Retrospective analysis of 24 patients with ICC who had undergone both preoperative CEUS proved by pathology.Sonographic examinations were performed with Technos DU8 and Philips IU22 ultrasound instruments using 2.5-3.5MHz curved-array transducers.Ultrasound contrast agent SonoVue was used. Results:All ICC lesions enhanced in the arterial phase with an initial time of 14.50s(5—20s) and a peak time of 22.29s(10—30s).The lesions displaying isoechoic and hypoechoic comparing with the hepatic parenchyma were 30.38s(14—50s) and 43.54s(21—90s),respectively.Then all lesions presented isoechoic or hypoechoic in the portal phase and in the late phase.Of the 24 patients,12(50%) showed whole-lesion enhancement and 12(50%) showed rim-like or thick bandlike enhancement.There were 70.8%(17/24) cases showing progressive dendritic and concentric filling of the contrast agent and 83.3%(20/24) cases showing heterogeneous enhancement during the peak enhancement.Of all patients,45.8% (11/24) cases presented lobular appearance during the CEUS examination especially in the portal phase and parenchyma phase.The accuracy of contrast-enhanced sonography was 83.3%(20/24) if the diagnostic feature included early wash-in and wash-out,progressive dendritic enhancement and/or heterogeneous enhancement. Conclusion:There are some specific findings in the CEUS which is useful in the diagnosis and differential diagnosis of this disease.Therefore CEUS may be more helpful in the diagnosis of ICC. Part Four:Comparison of enhancement features of peripheral intrahepatic cholangiocarcinoma on contrast-enhanced sonography and dynamic CT/MRIObjetive:To compare the enhancement features of ICC on contrast-enhanced sonography and CT/MRI.Methods:Thirteen ICC patients were examined with Esaote Technos DUB and Philips iU22 duplex systems and a contrast agent SonoVue. The results of CEUS were compared with those of enhanced CT/MRI.Results:All patients presented enhancement during the arterial phase on both contrast-enhanced sonography and dynamic CT and MRI.All cases showed hypoecho comparing to the surrounding liver parenchyma on the delayed phase.There were only 4 cases presented wash-out on the delayed phase while other 9 cases presented continuous enhancement.Seven(53.8%) cases showed peripheral enhancement patterns and 6 (46.2%) cases showed diffuse enhancement on enhanced sonography.The ratio was 62.5%(8/13) and 38.5%(5/13),respectively.Heterogeneous enhancement pattern was seen in 11(84.6%) case both on contrast-enhanced sonography and dynamic CT/MRI.and homogeneous enhancement pattern was seen in 3(15.4%) cases. Conclusion:Early enhancement at the arterial phase with following wash-out at the portal and late phase is an important sign of ICC,which can be used to differentiate malignant from benign tumors in liver.While on dynamic CT and MRI prolonged enhancement is a characteristic feature of ICC.In conclusion,ICC presents some characteristic features on sonogram but it also has diverse manifestations.It is hard to diagnose ICC before surgery on gray scale sonography.Color Doppler sonography can be used to evaluation the blood supply of the tumor and provide clinically useful information about the direction and the parameters(such as velocity,RI) of the blood flow,as well as the infiltration of the vessles.ICC presents some specific features including early wash-in and wash-out, progressive dendritic enhancement and/or heterogeneous enhancement on CEUS. While on dynamic CT and MRI prolonged enhancement is a characteristic feature of ICC.