Histology-Based Assessment of Sonazoid-Enhanced Ultrasonography for the Diagnosis of Liver Metastasis

This retrospective study aimed to assess the diagnostic performance of contrast-enhanced ultrasound with Sonazoid (S-CEUS) for liver metastasis. We enrolled in this study 98 patients with 148 histologically proven liver lesions, with 121 metastases and 27 non-metastases. The S-CEUS technique showed sensitivity in 95.0% (115 of 121), specificity in 44.4% (12 of 27) and accuracy in 85.8% (127 of 148) for the diagnosis of metastasis. Higher body mass index had a negative influence on the positive predictive value and accuracy, and a greater depth of the lesion had a negative influence on the accuracy. The management was changed in 8 patients (8.2%) because of S-CEUS findings. In conclusion, the addition of S-CEUS may offer a great benefit by improvement of the quality of diagnosis and management for patients with cancer who have a tentative diagnosis of liver metastasis by contrast-enhanced computed tomography.     

Radiofrequency ablation of very-early-stage hepatocellular carcinoma inconspicuous on fusion imaging with B-mode US: value of fusion imaging with contrast-enhanced US

Background/Aims

To determine the value of fusion imaging with contrast-enhanced ultrasonography (CEUS) and computed tomography (CT)/magnetic resonance (MR) images for percutaneous radiofrequency ablation (RFA) of very-early-stage hepatocellular carcinomas (HCCs) that are inconspicuous on fusion imaging with B-mode ultrasound (US) and CT/MR images.

Methods

This retrospective study was approved by our institutional review board and the requirement for informed consent was waived. Fusion imaging with CEUS using Sonazoid contrast agent and CT/MR imaging was performed on HCCs (<2 cm) that were inconspicuous on fusion imaging with B-mode US. We evaluated the number of cases that became conspicuous on fusion imaging with CEUS. Percutaneous RFA was performed under the guidance of fusion imaging with CEUS. Technical success and major complication rates were assessed.

Results

In total, 30 patients with 30 HCCs (mean, 1.2 cm; range, 0.6-1.7 cm) were included, among which 25 (83.3%) became conspicuous on fusion imaging with CEUS at the time of the planning US and/or RFA procedure. Of those 25 HCCs, RFA was considered feasible for 23 (92.0%), which were thus treated. The technical success and major complication rates were 91.3% (21/23) and 4.3% (1/23), respectively.

Conclusions

Fusion imaging with CEUS and CT/MR imaging is highly effective for percutaneous RFA of very-early-stage HCCs inconspicuous on fusion imaging with B-mode US and CT/MR imaging.     

Ablation therapy guided by contrast-enhanced sonography with Sonazoid for hepatocellular carcinoma lesions not detected by conventional sonography.

OBJECTIVE: We evaluated the usefulness of contrast-enhanced harmonic gray scale sonography with a newly developed sonographic contrast medium as a means of guidance for percutaneous ablation therapy of hepatocellular carcinoma lesions not detected by conventional sonography. METHODS: We examined 85 patients with 108 hepatocellular carcinoma lesions that were identified as hypervascular by multidetector-row computed tomography by using contrast-enhanced harmonic gray scale sonography after injection of Sonazoid (GE Healthcare, Oslo, Norway), a lipid-stabilized suspension of a perfluorobutane gas microbubble contrast agent. We scanned the whole liver by this modality at a low mechanical index in the late phase to detect lesions not detected by conventional sonography and then scanned the lesions again by this modality at a high mechanical index to visualize tumor vessels and enhancement. We also performed percutaneous ablation therapy guided by this modality to treat viable hepatocellular carcinoma lesions that could not be detected by conventional sonography. RESULTS: Conventional sonography identified 90 (83%) of 108 hepatocellular carcinoma lesions; 15 (14%) additional viable lesions not detected by conventional sonography were detected in the late phase of contrast-enhanced harmonic gray scale sonography at a low mechanical index, and tumor vessels and enhancement were observed in the late phase at a high mechanical index. Contrast-enhanced harmonic gray scale sonography diagnosed 105 (97%) of the 108 viable hepatocellular carcinoma lesions, and 14 (93%) of the 15 lesions not detected by conventional sonography were successfully treated by percutaneous ablation therapy guided by this modality. CONCLUSIONS: Contrast-enhanced harmonic gray scale sonography is useful for guidance of percutaneous ablation therapy of hepatocellular carcinoma lesions not detected by conventional sonography.     

Contrast-enhanced intraoperative ultrasonography equipped with late Kupffer-phase image obtained by sonazoid in patients with colorectal liver metastases

AIM： To find occult metastases during hepatectomy in patients with colorectal cancer liver metastases （CRCLM）, contrast-enhanced intraoperative ultrasonography （CE-IOUS） was performed using a new microbubble agent, sonazoid, which provides a parenchyma-specific contrast image based on its accumulation in the Kupffer cells. METHODS： Eight patients with CRCLM underwent CE- IOUS using sonazoid before hepatectomy. The liver was investigated during a late Kupffer-phase imaging, which is a valuable characteristic of sonazoid. RESULTS： CE-IOUS using sonazoid provided the early vascular- and sinusoidal-phase images for 10 min followed by the late Kupffer-phase image up to 30 min after the injection of sonazoid. IOUS did not provide new findings of metastatic lesion in the 8 patients. However, during the late Kupffer-phase image of sonazoid, a metastatic lesion was newly found in two of the 8 patients. These newly detected lesions were removed by an additional hepatectomy and histopathologically diagnosed as a metastasis. CONCLUSION： CE-IOUS using sonazoid can allow surgeons to investigate the whole liver with enough time and to find new metastases intraoperatively.     

Sono Vue与Sonazoid:机械指数及剂量变化与造影过程的定量分析

目的 比较SonoVue(Bracco,意大利)和Sonazoid(GE,挪威)在高频(7 MHz)条件下,剂量、机械指数(mechanical index,MI)与兔肝造影过程时间参数——上升时间(rising time,RT)、达峰时间(time-to-peak,TTP)的相关性.方法 分别对8只新西兰大白兔多次团注SonoVue(0.06 ml/kg、0.12 ml/kg)及Sonazoid(0.045 ml/kg、0.09 ml/kg)声学造影剂:SonoVue组每个剂量水平分别设置7个MI值(0.10～0.55);Sonazoid组每个剂量水平分别设置5个MI值(0.19～0.98).应用时间-强度曲线(time-intensity curve,TIC)做定量分析,并统计造影剂剂量和MI与RT、TTP的相关性.结果 在相同发射频率条件下:(1)SonoVue组1)0.06 ml/kg组在MI≤0.25范围内,RT、TTP未见明显变化(P＞0.05),之后随着MI增大RT、TTP呈下降趋势(P＜0.01);2)0.12 ml/kg组在MI≤0.40范围内,RT、TTP未见明显变化(P＞0.05),之后随着MI增大RT、TTP呈下降趋势(P＜0.01).(2)Sonazoid组1)0.045 ml/kg组随着MI增大RT、TTP未见明显变化(P＞0.05);2)0.09 ml/kg组在MI≤0.40范围内,RT、TTP未见明显变化(P＞0.05),之后随着MI增大RT、TTP呈上升趋势(P＜0.01).结论 2种造影剂理化特性各异,因此其超声造影效能各不相同,临床使用中应对其进行合理选择.     

Contrast enhanced ultrasound of hepatocellular carcinoma

Sonazoid (Daiichi Sankyo, Tokyo, Japan), a second-generation of a lipid-stabilized suspension of a perfluorobutane gas microbubble contrast agent, has been used clinically in patients with liver tumors and for harmonic gray-scale ultrasonography (US) in Japan since January 2007. Sonazoid-enhanced US has two phases of contrast enhancement: vascular and late. In the late phase of Sonazoid-enhanced US, we scanned the whole liver using this modality at a low mechanical index (MI) without destroying the microbubbles, and this method allows detection of small viable hepatocellular carcinoma (HCC) lesions which cannot be detected by conventional US as perfusion defects in the late phase. Re-injection of Sonazoid into an HCC lesion which previously showed a perfusion defect in the late phase is useful for confirming blood flow into the defects. High MI intermittent imaging at 2 frames per second in the late phase is also helpful in differentiation between necrosis and viable hypervascular HCC lesions. Sonazoid-enhanced US by the coded harmonic angio mode at a high MI not only allows clear observation of tumor vessels and tumor enhancement, but also permits automatic scanning with Sonazoid-enhanced three dimensional (3D) US. Fusion images combining US with contrast-enhanced CT or contrast-enhanced MRI have made it easy to detect typical or atypical HCC lesions. By these methods, Sonazoid-enhanced US can characterize liver tumors, grade HCC lesions histologically, recognize HCC dedifferentiation, evaluate the efficacy of ablation therapy or transcatheter arterial embolization, and guide ablation therapy for unresectable HCC. This article reviews the current developments and applications of Sonazoid-enhanced US and Sonazoid-enhanced 3D US for diagnosing and treating hepatic lesions, especially HCC.