Self-made ultrasound/fluorescent bi-functional contrast agent for rabbit's normal lymph node imaging / 中国医学科学院学报

<p><b>OBJECTIVE</b>To prepare a lymph node-targeted ultrasound/fluorescence bi-functional imaging contrast agents, and observe its effectiveness both on contrast-enhanced ultrasound (CEUS) and vivo near infrared fluorescence (NIR) imaging through animal experiments.</p><p><b>METHODS</b>The chimeric lymph node-targeted ligand (phosphatidylserine) and near-infrared fluorescent substance were assembled to form bi-functional contrast microbubbles. The morphology and size distribution were detected by optical microscope and Malvern potential tests. Five normal New Zealand white rabbits were subcutaneously injected with the prepared contrast agent in bilateral footpads, and the imaging effectiveness of lymph nodes and lymphatic vessel were observed by CEUS and NIR technique. Then blue dye was subcutaneously injected at the same site, and the rabbits were sacrificed for lymph nodes pathological examination.</p><p><b>RESULTS</b>Lipid ultrasound microbubbles,with a mean size of 3-5 Μm in diameter, appeared to be uniform in distribution and regular in configuration. The images of inflow lymphatic vessel and relevant lymph node were quickly showed up after the subcutaneous injection by CEUS, which was identical to the result detected by NIR. Biopsy confirmed that all the blue-stained lymph nodes could be displayed by NIR.</p><p><b>CONCLUSIONS</b>The self-made bi-functional contrast agent has a good imaging ability in CEUS and NIR imaging. It may be a better agent as lymph node tracer.</p>

Quantitative assessment of hepatic fibrosis by contrast-enhanced ultrasonography.

OBJECTIVE: To explore the contrast-enhanced ultrasonographic features for quantitative assessment of hepatic fibrosis. METHODS: 86 patients with chronic viral hepatitis B were enrolled in this study from March 2007 to August 2009. The patients were classified into 5 groups (S(0)-S(4)) according to fibrosis stage evaluated with ultrasound guided liver biopsy. New contrast-enhanced ultrasonography (CEUS) features including area under the time-intensity curve (TIC) of portal venous phase/hepatic arterial phase (Qp/Qa) and intensity of portal venous phase/hepatic arterial phase (Ip/Ia) were used to detect the blood supply ratio (portal vein/hepatic artery) in each group. Arrival time of portal vein trunk (Tp) and decreasing rate of TIC (ß) were also analyzed. RESULTS: Qp/Qa and Ip/Ia decreased from S(0) to S(4), while Tp and ß increased. These 4 features were significantly correlated with the degree of fibrosis (P<0.001) and were significantly different among the five groups (P<0.001). Sensitivity and specificity of Ip/Ia were 80% and 86% for groups ≥S(1), 75% and 86% for groups ≥ S(2), 71% and 84% for groups ≥ S(3), and 76% and 80% for group S(4), respectively. Sensitivity and specificity of Qp/Qa were 70% and 88% for groups ≥ S(1), 80% and 76% for groups ≥ S(2), 74% and 70% for groups ≥ S(3), and 81% and 95% for group S(4), respectively. CONCLUSION: Ip/Ia and Qp/Qa could be adopted as reliable, non-invasive features for quantitative assessment of hepatic fibrosis.