Study Of Gray Scale Contrast-enhanced Ultrasonography (SonoVue^?) In Infiltrative Belt Surroubding Hepatic Alveolar Echinococcosis

Object: To assess the accuracy of color Doppler ultrasonography in diagnosinghepatic alveolar echinococcosis, and evaluate the clear boundary and microvesselperfusion of the lesions and demonstrate the characteristic imaging and clinicalsignificance of HAE lesions by contrast-enhanced ultrasonography (CEUS), and tofurther investigate the expression of hypoxia inducible factor-1α (HIF-1α) andmicrovascular density (MVD) in the surrounding invasion range of HAE lesions andget the pathological basis of CEUS in HAE. Methods:1)129patients wereexamined at the First Affiliated Hospital of Xinjiang Medical University betweenJuly2004and June2010. Those patients suspected of having hepatic alveolarechinococcosis were examined and diagnosed by color Doppler ultrasound. All thecases were compared with the Gold Standard. The findings of their sensitivity,specificity, positive predictive value, negative predictive value, positive likelihoodratio, negative likelihood ratio, and95%confidence interval were recorded.2)Seventeen patients with19HAE lesions were examined in sequence with US, colorDoppler flow imaging (CDFI), and then CEUS before any treatment. All the datawere compared before surgery.3)23rats with hepatic echinococcus multilocularisinfection were examined by contrast-enhanced ultrasonography, and then obtainedtheir livers which had27HAE lesions. In accordance with the result of CEUS, thespecimens segments were made from119paraffin blocks. Tissue samples containedthe HAE nodules and the hepatic peranchyma of its surrounding and then proceededto the comparative analysis of immunohistochemical SP method. Results:1)Sensitivity:95%（95%confidence interval:90.7%~99.3%）; specificity:20.7%（95%confidence interval:6.0%~35.4%）; positive predictive value:80.5%; negative predictive value:54.5%; positive likelihood ratio:1.2: negative likelihood ratio:0.2.2) Examined by fundamental US,47.4%of HAE lesions showed irregularhyperechoic substantive areas,52.6%appeared as having a mixed echotype withirregular anechoic areas in the central portion of the lesions. The CDFI methodindicated no blood flow signals inside any of the19lesions. By CEUS, all19lesionsdisplayed circular rim enhancement in the peripheral segments, and absentenhancement within the central areas of the lesions (a ‘black hole’ effect). As a result,the lesions’ margins were clear, irregular and distinct. In general, the sizes of all theHAE lesions observed by CEUS were larger than those obtained by fundamental US.There was a significant difference among the two groups （P<0.05）.3) The twoimmunohistochemical staining methods were applied to the specimens segments ofthe HAE rats in this animal experiment, CD34and HIF-1α, and Expression ofHIF-1α and MVD were compared in surrounding invasion range and the hepaticperanchyma. The relationship between the expression of HIF-1α and MVD valuewas also calculated. HIF-1α positive expression rate was97.5%（116/119） andMVD was99.2%（118/119）. The expression of HIF-1α in the active multipliedinfiltrative region of the HAE lesion was significantly increased, compared with thehepatic peranchyma（P<0.05）. The expression of MVD in the active multipliedinfiltrative region of the HAE lesion was also significantly higher than the hepaticperanchyma（P<0.05）. And there was positive correlated between HIF-1α positiveexpression and MVD（P<0.05）. Conclutions:1) Our study indicates that colorDoppler ultrasonography, when used in diagnosing hepatic alveolar echinococcosis,has high sensitivity although specificity is low. Color Doppler ultrasound is thusconsidered to be an efficient means for diagnosing hepatic alveolar echinococcosis.2)CEUS is a simple imaging method and can be a helpful tool for more accurate sizingof HAE lesions and their surrounding invasion range, and the proper cut-off marginwhen radical hepatectomy is needed.3) The overexpression of HIF-α in the activemultiplied infiltrative region of the HAE lesion of the rats is closely related withangiogensis and microvasculature. HIF-1α is very sensitive and representation. It canindicate that the invasion range of HAE lesions was based on extrusion andcompression and caused the hepatic tissue anoxic and ischemic. It is valuableindexes in evaluating activity of HAE.