Yan-Ling Zheng

Characterization of small focal liver lesions using real-time contrast-enhanced sonography: diagnostic performance analysis in 200 patients.

Objective. The purpose of this study was to assess the diagnostic performance of real‐time contrast‐enhanced sonography in characterization of small focal liver lesions (FLLs; ≤3.0 cm in diameter). Methods. Two hundred small FLLs in 200 patients were examined by contrast‐enhanced sonography using a contrast‐specific mode of contrast pulse sequencing and a sulfur hexafluoride–filled microbubble contrast agent. The sonographic images were reviewed by 2 independent readers. A 5‐point confidence level was used to discriminate malignant from benign FLLs, and specific diagnoses were recorded. The diagnostic performances were evaluated by receiver operating characteristic (ROC) analysis, and the interobserver agreement was analyzed by weighted κ statistics. Results. After review of contrast‐enhanced sonography, ROC analysis revealed significant improvement in differentiating between malignant and benign small FLLs that the areas under the ROC curve were 0.856 at baseline sonography versus 0.954 at contrast‐enhanced sonography for reader 1 (P < .001) and 0.857 versus 0.954 for reader 2 (P = .003). The sensitivity, negative predictive value, and accuracy for both readers also improved significantly after contrast agent administration (all P < .001). A better result of specific diagnosis was obtained (38.5% [77/200] at baseline sonography versus 80.5% [161/200] at contrast‐enhanced sonography for reader 1 and 34.5% [69/200] versus 80.5% [161/200] for reader 2; both P < .001) after contrast agent administration, and a better interobserver agreement was achieved (κ = 0.425 at baseline sonography versus 0.716 at contrast‐enhanced sonography). Conclusions. Real‐time contrast‐enhanced sonography improves the diagnostic performance in small FLLs compared with baseline sonography.

Renal Cell Carcinoma and Renal Angiomyolipoma Differential Diagnosis With Real-time Contrast-Enhanced Ultrasonography

Objective. The purpose of this study was to evaluate the usefulness of contrast‐enhanced ultrasonography (CEUS) in differentiating renal cell carcinoma (RCC) from renal angiomyolipoma (RAML). Methods. One hundred nineteen patients with 126 renal lesions (33 RAMLs and 93 RCCs) who had undergone CEUS were retrospectively studied. All of the lesions were histopathologically or clinical proved. Contrast‐enhanced ultrasonography was performed using low–acoustic power modes and a sulfur hexafluoride–filled microbubble contrast agent. The baseline sonograms and CEUS images were retrospectively analyzed in consensus by 2 radiologists. The tumor echogenicity, enhancement patterns, and degree of enhancement at different phases were evaluated. The diagnostic efficacy of CEUS in differentiating the two diseases was computed and compared. Results. On CEUS, the features of wash‐out from hyperenhancement or isoenhancement to hypoenhancement over time (observed in 3.0% of RAMLs and 71.0% of RCCs; P < .001), heterogeneous enhancement (observed in 12.1% of RAMLs and 74.2% of RCCs; P < .001), and an enhanced perilesional rim (observed in 3.0% of RAMLs and 79.6% of RCCs; P < .001) achieved significant difference between RCCs and RAMLs. Early wash‐out and heterogeneous enhancement or peritumoral rim enhancement yielded the highest diagnostic capability in differentiating RCC from RAML. The corresponding sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 88.2% (82 of 93), 97.0% (32 of 33), 98.8% (82 of 83), 74.4% (32 of 43), and 90.5% (114 of 126), respectively. Conclusions. The CEUS features of early wash‐out, heterogeneous enhancement, and an enhanced peritumoral rim highly suggest RCC, whereas homogeneous enhancement and prolonged enhancement are characteristic manifestations of RAML. Contrast‐enhanced ultrasonography is valuable in differentiating RCC from RAML.

Imaging of Peripheral Cholangiocarcinoma With Low-Mechanical Index Contrast-Enhanced Sonography and SonoVue Initial Experience

Objective. The purpose of this study was to investigate the imaging findings of peripheral cholangiocarcinoma with low‐mechanical index (MI) contrast‐enhanced sonography. Methods. Eighteen nodules of peripheral cholangiocarcinoma proved by pathologic examination in 18 patients were evaluated with contrast‐enhanced sonography. A low‐MI real‐time contrast‐enhanced sonographic mode (ie, contrast pulse sequencing) and a sulfur hexafluoride‐filled microbubble contrast agent (SonoVue [BR1]; Bracco SpA, Milan, Italy) were used. Results. On contrast‐enhanced sonographic images, all 18 nodules (100%) of peripheral cholangiocarcinoma showed inhomogeneous enhancement during the arterial phase, and the emergence of nodule enhancement was earlier in 3 nodules (16.7%), simultaneous in 13 (72.2%), and later in 2 (11.1%), respectively, when compared with the adjacent liver tissue. During the arterial phase, 8 nodules (44.4%) showed irregular peripheral rimlike hyperenhancement, 2 (11.1%) showed inhomogeneous hyperenhancement, and 8 (44.4%) showed inhomogeneous hypoenhancement. In portal and late phases, all 18 nodules (100%) showed hypoenhancement. When contrast‐enhanced sonography was added for analysis, the confidence levels of the investigators were improved in 15 (83.3%) of 18 nodules, and 17 (94.4%) of 18 peripheral cholangiocarcinomas were correctly characterized. Conclusions. The imaging findings of peripheral cholangiocarcinoma had some characteristics on low‐MI contrast‐enhanced sonography. Knowledge of these characteristics might be beneficial for improving the diagnostic performance of sonography in evaluating this entity.

Real-time contrast-enhanced ultrasound imaging of infected focal liver lesions.

Objective. The purpose of this study was to investigate the features of infected focal liver lesions on contrast‐enhanced ultrasound (CEUS) imaging. Methods. Thirty‐two hepatic abscesses, 15 infected granulomas, and 6 inflammatory pseudotumors in 53 patients were evaluated with real‐time CEUS before awareness of the definitive diagnosis. A 2.4‐mL dose of a sulfur hexafluoride–filled microbubble contrast agent was administered by intravenous bolus injection. Results. The numbers of abscesses with hyperenhancement, isoenhancement, and hypoenhancement in the arterial phase were 26 (81.3%), 5 (15.6%), and 1 (3.1%), respectively. Thirty (93.8%) lesions were irregularly rim enhanced with nonenhanced areas; enhanced septa were shown in 22 (68.8%) lesions; and transient hyperenhancement of liver parenchyma around the lesion was shown in 20 (62.5%). In 31 abscesses with hyperenhancement or isoenhancement in the arterial phase, 25 (80.6%) showed contrast wash‐out and changed in appearance to hypoenhancement in the late phase. As for infected granulomas and inflammatory pseudotumors, 16 (76.2%) lesions showed hyperenhancement or isoenhancement in the arterial phase, and all of them were hypoenhanced in the portal and late phases. Conclusions. Most infected focal liver lesions showed more rapid contrast wash‐out than the surrounding liver parenchyma, which is similar to malignant lesions. Abscesses typically showed features of rim enhancement, enhanced internal septa, nonenhanced central necrotic areas, and transient hyperenhanced liver parenchyma around the lesions. The CEUS appearance of infected granulomas and inflammatory pseudotumors was variable, and a biopsy was necessary for definitive diagnosis.

Percutaneous thermal ablation for recurrent hepatocellular carcinoma after hepatectomy

Tumour ablation using a thermal energy source has shown promising results, and is particularly suitable for recurrent hepatocellular carcinoma (HCC). The present study evaluated long‐term outcomes after percutaneous thermal ablation for recurrent HCC following liver resection.

Sorafenib suppresses the rapid progress of hepatocellular carcinoma after insufficient radiofrequency ablation therapy: an experiment in vivo.

Background Radiofrequency ablation (RFA) is a widely applied treatment for hepatocellular carcinoma (HCC), but insufficient RFA can promote rapid progression of the residual tumor through the hypoxia inducible factor-1α (HIF-1α)/vascular endothelial growth factor A (VEGFA) pathway. Although sorafenib has been successfully applied to advanced HCC, the use of sorafenib in residual tumor cells after RFA has rarely been tested. Purpose To evaluate the potential role of sorafenib as an adjunct to RFA to reduce the recurrence rate after insufficient RFA. Material and Methods Xenograft tumors of SMMC 7721 were created by subcutaneously inoculating nude mice with hepatoma cells (5× 106 cells per mouse). Fourteen days after inoculation, all mice were divided into three groups (control group [sham puncture], RFA group, and RFA combined with sorafenib treatment group) with six mice in each group. Each group was given a different treatment procedure. After treatment, the volume of the tumors was calculated from the resected specimens. The mRNA and protein expression of HIF-1a and VEGFA was quantified by real-time PCR and immunohistochemistry analysis. The micro-vessel density (MVD) was determined by CD34 immunohistochemistry. Results Real-time PCR and immunohistochemistry analysis showed that, compared to the RFA group, HIF-1α and VEGFA expression were significantly decreased in the group that received RFA combined with sorafenib treatment (P < 0.05). By comparing the control group with the RFA group, we found that insufficient RFA promoted HIF-1α and VEGFA expression (P < 0.05). Similar results were obtained for MVD expression. Additionally, the combination of RFA with sorafenib therapy resulted in a synergistic reduction in tumor growth compared to insufficient RFA and sham puncture (P < 0.05). Conclusion Sorafenib was able to inhibit the expression of HIF-1α and VEGFA, and sorafenib was able to increase time to recurrence when used as an adjunct to RFA.

Shear wave elastography versus real-time elastography on evaluation thyroid nodules: A preliminary study

OBJECTIVE To comparatively evaluate shear wave elastography (SWE) and real-time elastography (RTE) in distinguishing malignant from benign thyroid nodules. METHODS 49 patients with 64 focal thyroid nodules were enrolled and underwent SWE and RTE before surgery. SWE elasticity indices (mean, minimum and maximum value of 2-mm region of interest) of nodules were measured. For RTE, elastograms were assessed by Rago criteria and nodules with scores of 4 or 5 were classified as suspicious for malignancy. Surgery histopathologic results were adopted as diagnostic standard. RESULTS Of the 64 nodules, 19 were papillary thyroid carcinomas and 45 were benign. SWE indices were significantly higher in malignant than benign nodules (P<0.05). Areas under the ROC curves (AUC) of SWE parameters were 0.840, 0.831 and 0.788, which were not significantly different from that of RTE showed as 0.880 (P=0.148-0.482). When the most accurate cut-off, 38.3kPa for mean value was applied to predict malignancy, the diagnostic specificity, sensitivity, accuracy, positive predictive value and negative predictive value of SWE and RTE were 68.4% versus 79.0%, 86.7% versus 84.4%, 81.3% versus 78.1%, 68.4% versus 64.7% and 86.7% versus 83.3%, respectively (P=0.683-1.000). CONCLUSION SWE as a promising tool can be performed in differentiating thyroid nodules with comparable results to RTE.

Optimizing the US Diagnosis of Biliary Atresia with a Modified Triangular Cord Thickness and Gallbladder Classification.

Purpose To evaluate the diagnostic performance of ultrasonography (US) in the identification and exclusion of biliary atresia with a modified triangular cord thickness metric together with a gallbladder classification scheme, as well as hepatic artery (HA) diameter and liver and spleen size, in a large sample of jaundiced infants. Materials and Methods The ethics committee approved this study, and written informed parental consent was obtained. In 273 infants with conjugated hyperbilirubinemia (total bilirubin level ≥ 31.2 μmol/L, with direct bilirubin level > indirect bilirubin level), detailed abdominal US was performed to exclude biliary atresia. Biliary atresia was found in 129 infants and ruled out in 144. A modified triangular cord thickness was measured at the anterior branch of the right portal vein, and a gallbladder classification scheme was identified that incorporated the appearance of the gallbladder and a gallbladder length-to-width ratio of up to 5.2 when the lumen was visualized, as well as HA diameter and liver and spleen size. Reference standard diagnosis was based on results of one or more of the following: surgery, liver biopsy, cholangiography, and clinical follow-up. Area under the receiver operating characteristic curve (AUC) analysis, binary logistic regression analysis, Fisher exact test, and unpaired t test were performed. Results Triangular cord thickness, HA diameter, ratio of gallbladder length to gallbladder width, liver size, and spleen size exhibited statistically significant differences (all P < .05) between the group with biliary atresia and the group without. AUCs of triangular cord thickness, ratio of gallbladder length to width, and HA diameter were 0.952, 0.844, and 0.838, respectively. Logistic regression analysis demonstrated that these three US parameters were significantly associated (all P < .05) with biliary atresia. The combination of triangular cord thickness and gallbladder classification could yield comparable AUCs (0.915 vs 0.933, P = .400) and a higher sensitivity (96.9% vs 92.2%), compared with triangular cord thickness alone. Conclusion By using the combination of modified triangular cord thickness and gallbladder classification scheme, most infants with biliary atresia could be identified. (©) RSNA, 2015.

Value of Contrast-Enhanced Ultrasonography in Assessing the Vascularity of Liver Metastases Comparison With Contrast-Enhanced Computed Tomography

Objective. The purpose of this study was to compare the capability of contrast‐enhanced ultrasonog‐raphy (CEUS) and contrast‐enhanced computed tomography (CECT) in evaluating the vascularity of liver metastases. Methods. Both CEUS and CECT examinations were performed on 70 patients with liver metastases, which were from colon carcinoma in 31, rectal carcinoma in 17, pancreatic carcinoma in 5, and others in 17. In patients with multiple lesions, the most easily observed lesion was selected as the target lesion for evaluation of vascularity. Results. Peak enhancement of the target lesion during the arterial phase was characterized as hyperenhancement, isoenhancement, hypo‐enhancement, and nonenhancement in 61 (87.1%), 6 (8.6%), 3 (4.3%), and 0 (0%) patients on CEUS, respectively, and in 52 (74.3%), 8 (11.4%), 8 (11.4%), and 2 (2.9%) on CECT. Contrast‐enhanced ultrasonography showed more lesions with hyperenhancement than CECT (P < .01). The enhancement pattern during the arterial phase was homogeneous, inhomogeneous, and rimlike in 30 (42.9%), 16 (22.9%), and 24 (34.2%) patients on CEUS and in 13 (18.6%), 8 (11.4%), and 49 (70%) on CECT. Contrast‐enhanced ultrasonography revealed more lesions with homogeneous enhancement than CECT (P < .01). Contrast‐enhanced ultrasonography showed dysmorphic vessels in 33 patients (47.1%) during the arterial phase, whereas CECT showed dysmorphic vessels in 27 (38.6%; P < .01). Contrast‐enhanced ultrasonography showed hypervascular lesions in 58.6% of patients, whereas CECT showed hypervascular lesions in 12.9% (P < .01). Conclusions. Contrast‐enhanced ultrasonography was superior to CECT in assessing the vascularity of liver metastases.

Does the echogenicity of focal liver lesions on baseline gray-scale ultrasound interfere with the diagnostic performance of contrast-enhanced ultrasound?

The objective was to evaluate whether the echogenicity of focal liver lesions (FLLs) on baseline gray-scale ultrasound (US) interferes with the diagnostic performance of contrast-enhanced US (CEUS) for small FLLs. Three-hundred and eighty-eight patients were examined by real-time CEUS using a sulfur hexafluoride-filled microbubble contrast agent. The images of 114 hyperechoic lesions, 30 isoechoic lesions and 244 hypoechoic lesions were reviewed by two blinded independent readers. A five-point confidence level was used to discriminate malignant from benign lesions, and specific diagnoses were made. The diagnostic performances were evaluated by receiver-operating characteristic (ROC) analysis. The diagnostic performances of CEUS on hyperechoic lesions in terms of the areas (Az) under the ROC curve were 0.987 (reader 1) and 0.981 (reader 2), and were 0.987 (reader 1) and 0.984 (reader 2) for iso- and hypoechoic lesions, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 87.0–95.9%, 93.1–100%, 88.6–100%, 70.0–97.1% and 90.0–95.1%, respectively. The echogenicity of FLLs on baseline gray-scale US does not appear to interfere with the diagnostic ability of CEUS for small FLLs.