M.-D. Lu

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.

Imaging features of intrahepatic biliary cystadenoma and cystadenocarcinoma on B-mode and contrast-enhanced ultrasound.

PURPOSE To investigate the imaging features of intrahepatic biliary cystadenoma and cystadenocarcinoma on B-mode and contrast-enhanced ultrasound. MATERIALS AND METHODS The B-mode and contrast-enhanced ultrasound features of 6 intrahepatic biliary cystadenomas and 7 intrahepatic biliary cystadenocarcinomas were retrospectively analyzed, and the differences between cystadenomas and cystadenocarcinomas were compared. RESULTS There were no significant differences between cystadenomas and cystadenocarcinomas in terms of patient gender, age, lesion location, size, and shape (all p > 0.05). On conventional ultrasound, biliary cystadenomas were more likely to be multilocular (6/6 for cystadenoma vs. 2/7 for cystadenocarcinoma) and cystadenocarcinomas more likely presented the features of a mural or septal nodule and a nodule diameter > 1.0 cm (0/6 for cystadenoma vs. 5/7 for cystadenocarcinoma). On contrast-enhanced ultrasound, hyper-enhancement (n = 4) or iso-enhancement (n = 2) was present in the cystic wall, septations or mural nodules of the cystadenomas during the arterial phase and the enhancement washed out to hypo-enhancement (n = 6) during the late phase. Cystadenocarcinomas also showed hyper-enhancement (n = 4) or iso-enhancement (n = 3) in the cystic wall, septations or mural nodules during the arterial phase and iso-enhancement (n = 1) or hypo-enhancement (n = 6) during the late phase. CONCLUSION Intrahepatic biliary cystadenomas are more typically multilocular cystic lesions. A mural or septal nodule and a nodule diameter greater than 1.0 cm on conventional ultrasound are suggestive of cystadenocarcinomas. Contrast-enhanced ultrasound is helpful for depicting the vascularity of the lesions but there was no significant difference between cystadenomas and cystadenocarcinomas.

Evaluation of the microcirculatory disturbance of biliary ischemia after liver transplantation with contrast‐enhanced ultrasound: Preliminary experience

The aim of this study was to determine the efficacy of contrast‐enhanced ultrasound for depicting the perfusion of hilar bile ducts in ischemic‐type biliary lesions after orthotopic liver transplantation. Thirteen transplant recipients with ischemic‐type biliary lesions and 12 patients without ischemic‐type biliary lesions underwent ultrasound examinations after the injection of 1.5 mL of an intravenous contrast agent. The enhancement of the hilar bile duct wall in the arterial, portal venous, and late phases was qualitatively graded as higher, equal, lower, or none with respect to that of the adjacent liver parenchyma. No or low contrast enhancement was seen in 10 of 13 patients (76.90%) with biliary ischemia, whereas increased contrast enhancement with respect to the normal liver parenchyma was found in all 12 patients without biliary ischemia. The difference in the enhancement patterns between the 2 groups was significant (P = 0.0001). In conclusion, contrast‐enhanced ultrasound is a new imaging modality to depict perfusion of the hilar bile duct. No or low contrast enhancement of the bile duct wall in the arterial phase may reflect the microcirculatory disturbance of biliary ischemia and may contribute to its early diagnosis. Liver Transpl 15:1703–1708, 2009.

Magnetic navigation in ultrasound-guided interventional radiology procedures

AIM To evaluate the usefulness of magnetic navigation in ultrasound (US)-guided interventional procedures. MATERIALS AND METHODS Thirty-seven patients who were scheduled for US-guided interventional procedures (20 liver cancer ablation procedures and 17 other procedures) were included. Magnetic navigation with three-dimensional (3D) computed tomography (CT), magnetic resonance imaging (MRI), 3D US, and position-marking magnetic navigation were used for guidance. The influence on clinical outcome was also evaluated. RESULTS Magnetic navigation facilitated applicator placement in 15 of 20 ablation procedures for liver cancer in which multiple ablations were performed; enhanced guidance in two small liver cancers invisible on conventional US but visible at CT or MRI; and depicted the residual viable tumour after transcatheter arterial chemoembolization for liver cancer in one procedure. In four of 17 other interventional procedures, position-marking magnetic navigation increased the visualization of the needle tip. Magnetic navigation was beneficial in 11 (55%) of 20 ablation procedures; increased confidence but did not change management in five (25%); added some information but did not change management in two (10%); and made no change in two (10%). In the other 17 interventional procedures, the corresponding numbers were 1 (5.9%), 2 (11.7%), 7 (41.2%), and 7 (41.2%), respectively (p=0.002). CONCLUSION Magnetic navigation in US-guided interventional procedure provides solutions in some difficult cases in which conventional US guidance is not suitable. It is especially useful in complicated interventional procedures such as ablation for liver cancer.

Three-dimensional contrast-enhanced ultrasonic cholangiography: A new technique for delineation of the biliary tract in a liver donor

Currently, intraoperative cholangiography using a radio-opaque contrast medium is widely used for visualizing the biliary tract before donor hepatectomy in living donor liver transplantation (LDLT). However, radiation exposure and adverse reactions to intravenous iodinated contrast have limited its clinical application. Ultrasonography could overcome these limitations if the bile ducts could be visualized adequately. Contrastenhanced ultrasound (CEUS) and 3-dimensional (3D) CEUS have been successfully used for depicting blood flow by the intravenous injection of microbubble contrast media. Recently, the value of intracavitary administration of microbubble contrast media in the diagnosis of vesico-ureteric reflux has been reported. We describe the use of 3D contrast-enhanced ultrasonic cholangiography (CEUSC) to delineate the biliary tree in an adult living liver donor through the injection of microbubble contrast media into the bile ducts intraoperatively.