Comparison Of Contrast Enhanced Ultrasound And Enhanced-CT In Diagnosis Of Liver Malignant Neoplasms

In recent years, contrast enhanced ultrasound (CEUS) has been proposed as a new method of ultrasound technique. Contrast-enhanced ultrasonography increases the accuracy of diagnosis. The sensitivity and specificity of CEUS are well correspondent with enhanced-CT.Objective: To compare the features of liver neoplasms on contrast enhanced dynamic gray scale ultrasonography and enhanced-CT.Methods: All the partners come form the patients in NO.2 hospital of Ji Lin university and Tumor hospital of Ji Lin province from Oct of 2005 to Oct of 2006. All cases have been proved hepatic tumors (including primary hepatic carcinoma 18 and secondary tumor of the liver 12) after operation or ultrasound-guided aspiration biopsy. The ultrasonound contrast agent SonoVue and an imaging technique of contrast pulse sequence were used in CEUS. SonoVue-enhanced ultrasonography and enhanced CT were performered on.Enhancement patterns of hepatic tumors on ultrasonography and CT in different phase were compared statistically.Results: Most liver neoplasms demonstrate hyperechoic in the arterial phase and hyperechoic in the portal and later phases on ultrasonography were similar to those on helical CT. The enhancement features of two hepatic tumors in different phases on ultrasonography and helical CT were of no significant difference statistically (p>0.05).Discussion: Contrast enhanced ultrasonography was performed at 4 minutes after contrast material injection. The observation will be divided into 3 phases: (1) arterial phase, from 0 second to 40 second; (2) portal phase, from 40 second to 120 second; (3) delayed phase, after 120 second. Most primary hepatic carcinoma were characterized by quick wash-in and wash-out (high and rapid peak of enhancement in the arterial phase, followed by a relative quick wash-out in the portal phase) Most masses of secondary tumor of the liver appeared as"black hole"sign in the late phase, which were similar with the appearance of enhanced-CT.Advantages of CEUS: First, CEUS provides a simple and accurate method for characterization of liver tumor. Second, contrast agent of ultrasonography is chaotic per-tumoral and intra-lesional tortuous vessels and irregular vascular lakes. Third, CEUS is real-time examination, which is better than enhanced-CT.Disadvantages of CEUS: First of all, hepatic lesions with little blood supply cannot be enhanced, so they are difficult to detect. Secondly, the time for examination is so short that it is difficult to detect all masses in liver.Conclusions: Contrast- enhanced ultrasonography increases the accuracy of diagnosis. Its sensitivity and specificity are well correspondent with enhanced-CT. Contrast- enhanced ultrasonography will provide much significant message for clinical diagnosis.