Objective:

To evaluate the value of contrast-enhanced ultrasound (CEUS) in the diagnosis of 10 mm hepatocellular carcinoma (HCC).

Methods:

Thirty-four cases with pathologically proven 10 mm HCC were enrolled in this study and the image features on CEUS were analyzed retrospectively.

Results:

All cases were hyper-enhanced in arterial phase. 61.8% (21/34) were hypoenhanced and 38.2% (13/34) were iso-enhanced in portal venous phase. In those cases with iso-enhancement in portal vein phase

7 cases showed hypo-enha

ncement and 6 cases showed iso-enhancement in delayed phase. The average enhancement initial time

the time to peak

the time to isoechogenity

and the time to hypoechogenicity were (18.563.94)

(23.884.59)

(32.336.54)

and (134.2166.38) s

respectively. The diagnostic accuracy was 61.8% if the diagnostic standard for 10 mm HCC was set as hyperenhancement in arterial phase and hypo-enhancement in portal venous and delayed phases; However

the diagnostic accuracy was improved to 82.4% if the standard was hypo-enhancement in arterial phase and hypo-enhancmeent or iso-enhancement in portal venous phase and hypo-enhancement in delayed phase. Furthermore

the diagnostic accuracy was improved to 91.1% when combining HCC history.

Conclusion:

Analysis of contrast phase for 10 mm HCC might be helpful in improving the diagnostic accuracy.