Doppler in Portal Hypertension

Abstracts strictures, including benign and malignant etiologies. Most biliary tract strictures are of malignant etiologies, such as pancreatic adenocarcinoma, cholangiocarcinoma, peri-ampullary cancer, gallbladder cancer, hepatocellular carcinoma, lymphoproliferative diseases, and metastatic disease. The benign causes of biliary tract stricture include inflammatory stricture, gall stone related Mirizzi’s syndrome, chronic pancreatitis, primary scelrosing cholangitis, IgG4-related sclerosing cholangitis, iatrogenic bile duct injury following cholecystectomy and choledocholithotmy, and post-transplant strictures. The differentiation between benign and malignant strictures is very importance. Missing a diagnosis of malignant biliary stricture may result in delayed operation and impaired prognosis. However, up to 20% of patients with benign etiologies may receive unnecessary operation under the suspicion of malignant biliary strictures. Transabdominal ultrasonography, multi-detector computed tomography (MDCT), or magnetic resonance imaging (MRI) are traditionally used to detect and to differentiate the biliary tract strictures. Endoscopic retrograde cholangiopancreatography (ERCP) is considered the gold standard diagnostic and therapeutic method for the biliary strictures. Endoscopic ultrasound (EUS) is increasingly being used in the evaluation of patients with biliary obstruction, especially for the distal biliary strictures. It has high sensitivity and accuracy for the diagnosis of malignant biliary tract strictures. EUS guided fine needle aspiration can provide the tissue diagnosis of biliary stricture, though the puncture tract seeding and peritoneal seeding is still a topic of concerns. With the continuing improvement of EUS and the development of accessories, EUS plays not only a diagnostic tool, but also an interventional modality to manage of biliary strictures. EUS guided tumor ablation, EUS guided pain control, EUS guided pancreatico-biliary drainage, and EUS guided gastrointestinal tract bypass are promising applications of EUS in the biliary tract strictures. T12-16-IN11 Expanding Role of US in Diagnosis of Portal Hypertension and Cirrhotic Complications Soon Koo Baik, MD, PhD Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, South Korea Color Doppler Ultrasonography (CD-US) has an advantage of being non-invasiveness, so many attempts to investigate the hemodynamic alterations in cirrhosis and the response to medical treatment of portal hypertension as well as morphologic change of liver have been made. In particular, any CD-US parameter that could be a suitable substitute for the invasive current gold standard for assessing portal hypertension by measuring hepatic venous pressure gradient (HVPG) and hepatic fibrosis evaluated by liver biopsy, would be highly desirable. The presence of intrahepatic shunts resulting from portal hypertension can be helpful to diagnosis of portal hypertension and cirrhosis through novel characteristic CD-US index. It has been recently suggested that the extent of abnormality in Doppler hepatic vein (HV) waveform is associated with degree of HVPG as well as severity of hepatic fibrosis, and a change in HV waveform is closely correlated with that in HVPG. Abnormal flattened HV wave form is thought to be due to hemodynamically blunting the effect of variations in central venous pressure during the cardiac cycle, which is arising from increased HV inflow via intrahepatic shunts secondary to portal hypertension. Moreover, under microbubble contrast enhancement, CD-US detection of decreased hepatic vein transit time due to presence of intrahepatic shunts can be useful to assess the severity of portal hypertension and grade of fibrosis. However, for being reproducible and accurate, a cooperative training program of operators with strict examination protocol would be helpful to reduce the rate of intra-and inter-observer variation.

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Consequently, developments of novel CD-US indices and techniques are ongoing to overcome the limitations of conventional CD-US methods in diagnosis of portal hypertension and cirrhosis, and some of them are enough to potentially allow widespread clinical use. T12-16-IN12 Role of Microbubble-Based Contrast-Enhanced Ultrasound for the Assessment of Portal Hypertension Hitoshi Maruyama, MD, PhD Department of Gastroenterology, Chiba University Graduate School of Medicine Given the high incidence of chronic liver diseases, particularly in Asian Pacific region, diagnosis of portal hypertension (PH) is a key process in the daily medical care. The severity of PH is determined by the portal pressure, which is closely associated with the clinical manifestations and prognosis of cirrhosis patients. Hepatic venous catheterization is the only method to assess the hepatic venous pressure gradient (HVPG), a surrogate marker for directly measured portal pressure. However, because it is an invasive method involving a radiation exposure, non-invasive markers repeatedly available during the long-term clinical course are required. Ultrasound (US) offers non-invasive and real-time evaluations for an anatomical structures and hemodynamics under physiological conditions. It may be the most frequently used imaging tool in the practical management of cirrhosis patients. Furthermore, with the development of digital imaging technologies and the availability of microbubble contrast agents, contrast-enhanced US may now be the definitive primary modality for detailed evaluation. Efforts have been directed at finding the benefits of this technique for the severity of liver disease in order to decrease the requirement for invasive procedures. With these backgrounds, this presentation shows the recent progress in the application of contrast-enhanced US as the non-invasive assessment of PH. T12-16-IN13 Doppler in Portal Hypertension Antonio Carlos Matteoni de Athayde (Brazil) Portal hypertension is a frequent complication in patients with chronic parenchymal liver disease, as can also occur in other entities, such as portal vein pathology. The B-mode echography demonstrates the portal vein dilation and the presence of collateral circulation. It is very important to seek to identify if there is collateral circulation, especially of the veins responsible for drainage of the lower esophagus, which will lead to the formation of esophageal varices, which may cause bleeding, a situation that can lead to life risk for the patient. The color Doppler is very useful to identify presence of flow in the portal vein, direction of the same, and associated with spectral Doppler measure the velocity, which can help to diagnose portal hypertension in portal veins of normal caliber. In the collateral circulation the color Doppler reveals the existence of flow and associated with the spectral Doppler characterize to treat effectively of venous vessels, and also the direction of the flow. T12-16-IN14 The Role of Doppler Ultrasound in Cirrhosis Ja-Der Liang Gastroenterology and Hepatology, National Taiwan University Hospital, Taiwan In clinical hepatology, ultrasound (US) examination is necessary and widely used tool for disease diagnosis, assessment and monitoring. With prevalent viral hepatitis in Taiwan, both conventional