Preliminary Study Of Contrast-Enhanced Ultrasound In The Focal Liver Lesions Diagnosis

Objective To discuss the diagnostic value of contrast-enhanced ultrasound in focal liver lesions (FLL) .Methods Contrast-enhanced ultrasound were performed on 56 patients , with 90 focal liver lesions, including 24 primary liver cancers, 43 metastatic liver tumors, 19 hepatic hemangiomas, 3 focal fatty sparing of liver, and 1 liver tuberculosis necrotic lesion.Results 10 (41.7%) of primary liver cancers presented homogeneous and 14 (58.3 %) presented inhomogeneous enhancement in the arterial phase, presented low-echo in the parenchymal phase; the perfusion patterns of 43 liver metastasis lesions were in four types: 20(46.5%) presented homogeneous enhancement in the arterial phase, 14 (32.6%) presented rim-like and flocky enhancement, 6 (14.0%) presented peripheral ramose and centripetal fill-in enhancement, and 3 (6.9%) presented no obvious enhancement, presented low-echo"lacking" area in the parenchymal phase; in 19 hemangiomas, 14 (73.7%) presented ring with peripheral small nodular enhancement in the arterial phase, 5 (26.3%) presented peripheral mosaic and nodular enhancement, presented centripetal fill-in from portal phase to parenchymal phase in majority ; 3 "liver focal fatty sparing" enhancement presented no obvious different with peripheral liver parenchyma in the arterial phase, portal venous phase and parenchymal phase, low echo area disappeared; 1 liver tuberculosis necrotic lesion presented no obvious enhancement from the arterial phase to parenchymal phase. The initiation time of enhancement in liver metastasis was significantly different compared to primary liver cancers (P<0.05) . Presented homogeneous enhancement in the cases with small(≤3cm) primary liver cancers , and 87.5% (14/16) presented inhomogeneous enhancement in the largers (>3cm); 15(75.0%) small tumors (≤3cm) of 20 liver metastasis presented homogeneous enhancement. the perfusion patterns of malignant FLLs were linked with size, blood vessel and putrescence. The larger hemangiomas (>3cm) mostly presented to be peripheral mosaic and nodular enhancement. The sensitivity, specificity, positive predicative value, negative predicative value and accuracy of the contrast-enhanced ultrasound in identifying malignant FLLs were 95.5% (64/67), 91.3%(21/23), 97.0% (64/66), 87.5% (21/24), 94.4% (85/90) .Conclusion Different FLL showed different enhancement patterns of the contrast-enhanced ultrasound, which provide the new basis for the differential diagnosis of FLL; real time gray-scale contrast tuned imaging was a useful technique in differential diagnosis of FLL.