Computer-Aided Diagnosis of Focal Liver Lesions Using Contrast-Enhanced Ultrasonography With Perflubutane Microbubbles

Contrast-enhanced US for characterization of focal liver lesions: a comprehensive meta-analysis

OBJECTIVES

This meta-analysis was performed to evaluate the accuracy of contrast-enhanced ultrasound (CEUS) in differentiating malignant from benign focal liver lesions (FLLs).

METHODS

Cochrane Library, PubMed and Web of Science databases were systematically searched and checked for studies using CEUS in characterization of FLLs. Data necessary to construct 2×2 contingency tables were extracted from included studies. The QUADAS tool was utilized to assess the methodologic quality of the studies. Meta-analysis included data pooling, subgroup analyses, meta-regression and investigation of publication bias was comprehensively performed.

RESULTS

Fifty-seven studies were included in this meta-analysis and the overall diagnostic accuracy in characterization of FLLs was as follows: pooled sensitivity, 0.92 (95%CI: 0.91-0.93); pooled specificity, 0.87 (95%CI: 0.86-0.88); diagnostic odds ratio, 104.20 (95%CI: 70.42-154.16). Subgroup analysis indicated higher diagnostic accuracy of the second-generation contrast agents (CAs) than the first-generation CA (Levovist; DOR: 118.27 vs. 62.78). Furthermore, Sonazoid demonstrated the highest diagnostic accuracy among three major CAs (SonoVue, Levovist and Sonazoid; DOR: 118.82 vs. 62.78 vs. 227.39). No potential publication bias was observed of the included studies.

CONCLUSION

CEUS is an accurate tool to stratify the risk of malignancy in FLLs. The second-generation CAs, especially Sonazoid may greatly improve diagnostic performance.

KEY POINTS

• CEUS shows excellent diagnostic accuracy in differentiating malignant from benign FLLs. • The second-generation CAs have higher diagnostic accuracy than first-generation CAs. • Sonazoid demonstrates the highest diagnostic accuracy among three major CAs.

Combination of acoustic radiation force impulse imaging, serological indexes and contrast-enhanced ultrasound for diagnosis of liver lesions

AIM

To assess the value of combined acoustic radiation force impulse (ARFI) imaging, serological indexes and contrast-enhanced ultrasound (CEUS) in distinguishing between benign and malignant liver lesions.

METHODS

Patients with liver lesions treated at our hospital were included in this study. The lesions were divided into either a malignant tumor group or a benign tumor group according to pathological or radiological findings. ARFI quantitative detection, serological testing and CEUS quantitative detection were performed and compared. A comparative analysis of the measured indexes was performed between these groups. Receiver operating characteristic (ROC) curves were constructed to compare the diagnostic accuracy of ARFI imaging, serological indexes and CEUS, alone or in different combinations, in identifying benign and malignant liver lesions.

RESULTS

A total of 112 liver lesions in 43 patients were included, of which 78 were malignant and 34 were benign. Shear wave velocity (SWV) value, serum alpha-fetoprotein (AFP) content and enhancement rate were significantly higher in the malignant tumor group than in the benign tumor group (2.39 ± 1.20 m/s vs 1.50 ± 0.49 m/s, 18.02 ± 5.01 ng/mL vs 15.96 ± 4.33 ng/mL, 2.14 ± 0.21 dB/s vs 2.01 ± 0.31 dB/s; P < 0.05). The ROC curve analysis revealed that the areas under the curves (AUCs) of SWV value alone, AFP content alone, enhancement rate alone, SWV value + AFP content, SWV value + enhancement rate, AFP content + enhancement rate and SWV value + AFP content + enhancement rate were 85.1%, 72.1%, 74.5%, 88.3%, 90.4%, 82.0% and 92.3%, respectively. The AUC of SWV value + AFP content + enhancement rate was higher than those of SWV value + AFP content and SWV value + enhancement rate, and significantly higher than those of any single parameter or the combination of any two of parameters.

CONCLUSION

The combination of SWV, AFP and enhancement rate had better diagnostic performance in distinguishing between benign and malignant liver lesions than the use of any single parameter or the combination of any two of parameters. It is expected that this would provide a tool for the differential diagnosis of benign and malignant liver lesions.