Study on hepatocellular carcinoma-associated hepatic arteriovenous shunt using multidetector CT

AIM: To investigate multidetector CT (MDCT) findings of hepatocelluar carcinoma (HCC)- associated hepatic arteriovenous shunt (HAVS) and to evaluate their clinical significance. METHODS: Thin-slice and dynamic enhancement MDCT of HAVS was performed on 56 patients with HCC. MDCT findings, including those of portal veins, hepatic veins, superior mesenteric veins, splenic veins, HCC foci, liver parenchyma without HCC foci, spleens, and thromboses in portal veins and hepatic veins, were all confirmed by digital subtract angiography and analyzed. RESULTS: MDCT demonstrated earlier enhancement of main portal trunks and/or the first order branches than that of superior mesenteric veins or splenic veins (n=31). One patient had strong early enhancement of left hepatic vein with thromboses in left hepatic vein and upper part of inferior vena cava and 1 patient had transient patchy enhancement peripheral to HCC foci in late hepatic arterial phase among them. It demonstrated stronger opacification of main portal trunks and/or the first order branches than that of superior mesenteric veins or splenic veins (n=18), and earlier enhancement of the second order and smaller branches of portal veins than that of main portal trunks (n=4), stronger opacification of the second order and smaller branches of portal veins than that of main portal trunks (n=3), with transient patchy enhancement (n=3) or wedge-shaped enhancement (n=4) peripheral to HCC foci in late hepatic arterial phase. Enhancement degree of HCC foci was all decreased. As for 49 patients with severe or moderate shunts, enhancement degree of liver parenchyma without HCC foci was increased with heterogeneous density, but enhancement degree of spleens was decreased. There were thromboses in main portal trunks and/or the first order branches in 32 patients. CONCLUSION: The main MDCT findings of HCC-associated HAVS are earlier enhancement and stronger opacification of portal veins and/or hepatic veins. Understanding of these findings will contribute to the diagnosis and prognosis of the disease and improve therapy for the patients.     

大肠癌肝内转移灶分布研究

目的 为了探讨门静脉内是否存在血液流线型分流以及这种以是否影响大肠癌转移灶在肝内的分布，为防治方法及途径提供依据。方法 根据肠系膜上、下动脉供血范围没，以脾曲为界，将整个大肠分为左右两阗，分别观察各半结肠癌在肝内左右两叶转移灶的分布情况。结果和结论 肠系膜上、下静脉及脾静脉在汇入门静脉后，其血液并未完全混合，存在流线型血液分流，且对肝内转移灶的分布造成影响。右半结肠癌者的肝内转移灶多分布在肝右叶，     

Histological evaluation of intracapsular venous invasion for discrimination between portal and hepatic venous invasion in hepatocellular carcinoma

Background and Aim:  Histological criteria for intracapsular venous invasion (IVI) that would allow its discrimination between portal and hepatic venous invasion in hepatocellular carcinoma (HCC) have not been established.
Methods:  We evaluated IVI immunohistochemically to discriminate between portal and hepatic venous invasion in 89 resected specimens from patients with HCC. IVI was defined as the microscopic involvement of the vessels within the fibrous capsule of HCC. The hepatic venous system was subdivided into the central vein and the sublobular/hepatic vein. Immunohistochemical analysis with the D2-40 monoclonal antibody revealed lymphatic vessels.
Results:  In non-neoplastic liver tissues, the portal veins ( n  = 4355) were accompanied by lymphatic vessels (99.7%), bile ductules (100%) and arteries (96%), whereas the central veins ( n  = 3932) and sublobular/hepatic veins ( n  = 662) were rarely accompanied by lymphatic vessels (0% and 17%, respectively) and bile ductules (12% and 33%, respectively). In total, 29 IVI foci were detected; three foci were clearly visible within vessels that contained a distinct layer of connective tissue fibers, signifying sublobular/hepatic venous invasion. As the remaining 26 foci were accompanied by lymphatic vessels (26/26 [100%]), bile ductules (21/26 [81%]) and arteries (10/26 [38%]), these foci were considered to reflect intracapsular portal venous invasion rather than venous invasion of the central vein. Intracapsular portal venous invasion was significantly associated with extratumoral portal venous invasion ( P  < 0.001).
Conclusions:  D2-40 immunoreactivity for the histological evaluation of IVI in HCC allows discrimination between portal and hepatic venous invasion for cases in which portal venous invasion predominates.     

Role of portal and splenic vein shunts and impaired hepatic extraction in the elevated serum bile acids in liver cirrhosis

To study the mechanism for the elevation of serum bile acids in liver cirrhosis, bile acid concentrations were measured in the portal, superior mesenteric, and splenic veins, using percutaneous transhepatic catheterization, and compared with those of peripheral veins in 41 patients with mild to moderately advanced cirrhosis. The demonstrated gradient of bile acid concentration was superior mesenteric vein greater than portal vein greater than peripheral vein nearly equal to splenic vein, suggesting that the superior mesenteric vein is the main route of transport for the intestinally absorbed bile acids. Bile acid concentrations in peripheral vein were correlated with the measured portal and splenic vein shunt indexes. The ursodeoxycholic acid oral tolerance test carried out in 10 patients during portal vein catheterization demonstrated that hepatic extraction of this bile acid was correlated with indocyanine green clearance and that it was inversely correlated with portal vein shunt index. These findings are consistent with the view that distorted hepatic blood flow has a significant role in elevating serum bile acid, at least in patients with moderately advanced liver cirrhosis.     

Hepatic Encephalopathy Associated with Extensive Portal Hepatic Venous Shunts: A Case Report

Extensive intrahepatic portal-hepatic venous anastomosis is very rare. This report describes a 47-year-old man with cirrhosis who presented with mental confusion and flapping tremor, and in whom percutaneous transhepatic portography and superior mesenteric angiography demonstrated shunting between the portal vein branches and the right hepatic vein. Measurements of pressure, ammonia, and immunoreactive insulin in blood of the portal and right hepatic veins clearly indicated that a large amount of portal vein blood was being shunted into the right hepatic vein. These findings suggest that hepatic encephalopathy in this patient is accounted for at least in part by an intrahepatic portal-hepatic venous shunting.     

Dynamic helical biphasic CT emerges as a potential tool for the diagnosis of proximal arterioportal shunting.

BACKGROUND/AIMS: This article reports our preliminary observation regarding the diagnostic ability of dynamic helical biphasic computed tomography (CT) for proximal arterioportal shunting in hepatoma patients as compared with that of conventional angiography. METHODOLOGY: Three hundred and sixty patients with clinically-suspected liver lesions received both dynamic helical biphasic CT scan and conventional angiography of the liver. The criteria for diagnosis of proximal arterioportal (AP) shunting in dynamic helical biphasic CT included early and strong enhancement of main portal vein or its major branches approaching the density of the aorta, or enhancement of the portal vein earlier than opacification of the splenic vein and superior mesenteric vein in the arterial phase. The angiographic diagnosis of proximal AP shunting was made if there was early opacification of the main portal vein or its major branches in the arterial phase. Peripheral subsegmental small AP shunting was excluded from our study. The existence and extent of AP shunting were compared in these two imaging modalities. RESULTS: Dynamic helical biphasic CT scan demonstrated proximal AP shunting in 23 patients. All of these patients harbored hepatoma. Conventional angiography showed proximal AP shunting in 20 patients, which were all positive on dynamic helical CT. Dynamic helical biphasic CT demonstrated the presence of proximal AP shunting in 3 more patients than conventional angiography did. The extent of AP shunting was well correlated between these two imaging modalities in 17 patients. CONCLUSIONS: From our preliminary experience, the diagnostic accuracy of dynamic helical biphasic CT for proximal AP shunting in patients with hepatoma seemed to be comparable to, or even surpassed that of conventional angiography. It seems that faint AP shunting in patients with large hepatoma might be missed by conventional angiography.     

Multidetector CT in evaluating blood supply of hepatocellular carcinoma after transcatheter arterial chemoembolization

AIM: To assess the value of multidetector-row computed tomography (MDCT) in choosing retreatment methods of hepatocellular carcinoma (HCC) through evaluating the blood supply of low-density area of HCC after transcatheter arterial chemoembolization (TACE). METHODS: Thirty-two patients with HCC after TACE treatment were examined by plain scanning and hepatic multidetector-row CT. The location of low-density area on plain scanning and the enhancement patterns on dynamic contrast-enhanced scanning were observed. At the same time, three-dimensional CT (3D CT) models of the volume rendering, curved multiplanar reformations, surface shaded display and maximum intensity projection reconstruction of the hepatic artery and portal vein were performed in 6 cases. RESULTS: In CT plain scanning data, low density areas of 32 cases of HCC after TACE treatment were divided into three types: peripheral, one-side-located and mixed types. In contrast-enhanced CT scans, the blood supply of low-density area was classified into four types: arterial blood supply (20 cases), portal blood supply (5 cases), arterial combined with portal blood supply (5 cases) and poor blood supply (2 cases). In 6 cases, the relationship between the low-density area and branches of hepatic artery as well as portal vein was shown by 3D CT. CONCLUSION: Hepatic MDCT is an effective method for evaluating the blood supply of low-density area and therapeutic effect of HCC after TACE treatment. Types of blood supply is helpful for the selection of retreatment.     

Primary antiphospholipid syndrome presenting with abdominal angina and splenic infarction

The antiphospholipid syndrome is an autoimmune hypercoagulability syndrome in which a wide variety of thromboembolic diseases may occur. Gastrointestinal manifestations associated with vascular occlusion include Budd-Chiari syndrome, hepatic and splenic infarction, pancreatitis, omental and intestinal infarction, and esophageal variceal bleeding due to portal vein thrombosis, but chronic mesenteric ischemia associated with mesenteric arterial thrombosis is very rare in this syndrome. We experienced a female patient with primary antiphospholipid syndrome with abdominal angina and splenic infarction associated with celiac trunk and mesenteric arterial thromboses. This is the first report describing chronic mesenteric ischemia and splenic infarction in a patient with primary antiphospholipid syndrome.     

Extensive calcifications in portal venous system in a patient with hepatocarcinoma

Calcification of the portal venous system is a rare entity that can be incidentally discovered during computed tomography(CT).We describe a case of extensive calcifications in the portal venous system in a middleaged male patient with hepatocellular carcinoma(HCC).This patient presented with epigastric pain that had no obvious origin prior to admission.Laboratory examinations were positive for hepatitis B surface antigen andα-fetoprotein,and severe esophageal and gastric varices were detected during gastroscopy.Abdominal X-ray plain film showed well-defined linear and tracklike calcification,with irregular margins directed along the course of the portal venous system.CT revealed extensive calcifications along the course of the portal,splenic,superior mesenteric and gastroesophageal veins.He underwent splenectomy 22 years ago due to splenomegaly and partial hepatectomy seven months before because of HCC of low-grade differentiation,confirmed by pathology.Finally,the patient was diagnosed with postoperative recurrent HCC and extensive portal venous system calcification after selective hepatic angiography under digital subtraction angiography.     

Panhepatography: Simultaneous radiographic visualization of all hepatic veins

Summary Panhepatography, a new method of hepatic phlebography by means of a single injection of contrast medium into the inferior vena cava, is described. Simultaneous arrest of caval flow during injection of contrast medium into the vena cava near the outlet of the hepatic veins enables opacification of all the hepatic veins and their branches. Because of the block at the level of the caval vein, the contrast medium follows a retrograde flow into the hepatic veins.The method was developed in 76 experiments on 36 dogs and applied clinically in 1 patient. In the animal experiments good visualization of all the hepatic veins and their branches was obtained. In one clinical trial on a patient suffering from portal hypertension and hypersplenism, the main right hepatic vein and the large accessory hepatic vein were clearly outlined, as well as their small branches.I believe that it is feasible to opacify all of the hepatic veins in man.The work described in this paper was carried out in collaboration with the Departments of Operative Technique and Experimental Surgery and of Radiology Faculty of Medicine, University of Minas Gerais, Belo Horizonte, Brazil.     

Venous thrombosis in gastroenterology

Venous thrombosis involving the digestive tract affects the suprahepatic veins and the terminal part of the inferior vena cava, the portal vein and its roots. The etiology and diagnosis of this condition have made considerable progress. A thrombogenic disease can now be recognized in 90% of cases of involvement of the suprahepatic veins, and 75% of portal involvements. The most frequent causes are primary myeloproliferative syndromes, paroxysmal nocturnal hemoglobinuria, hereditary deficiency in coagulation proteins and circulating anticoagulants. The cause of involvement of the portal vein also include insults during biliary surgery and abdominal infections, particularly those caused by Bacteroides fragilis. Mechanical involvement due to compression finally plays a minor role in the etiology. Noninvasive techniques of diagnosis are now available, including ultrasound, computed tomography and magnetic resonance imaging. The expression of obstruction of the suprahepatic veins predominantly consists in ascites and hepatomegaly. Thrombosis of the portal vein preserving the mesenteric arches usually remains asymptomatic until the intrahepatic block is revealed by a digestive hemorrhage caused by portal hypertension. Isolate involvement of the splenic vein exceptionally causes the rupture of gastric or esophageal collateral veins. The treatment should combine the prevention of further thromboses by anticoagulants and the specific treatment of the venous obstruction. In case of suprahepatic obstruction, there are several methods of restoring a canal of drainage for hepatic blood. Their indications depend on the patency of the inferior vena cava and of the portal vein. In case of portal obstruction, portal-systemic bypass is feasible only if one of the major roots of the portal vein still is patent.(ABSTRACT TRUNCATED AT 250 WORDS)     

Capability of multidetector CT to diagnose hepatocellular carcinoma-associated arterioportal shunt

AIM: To investigate the capability of multidetector CT (MDCT) to diagnose HCC-associated arterioportal shunt (APS). METHODS: Two hundred and eighty-two patients with HCC received both thin-slice and enhancement MDCT scanning at early hepatic arterial phase, late hepatic arterial phase and portal venous phase, and digital subtract angiography (DSA) examination. Images were analyzed jointly by two experienced radiologists blinded to the opposite examination results, including the existence or not of APS, shunt locations, types and degrees of APS, with or without thrombosis. RESULTS: There were 56 APS associated with HCC, including 48 central, seven peripheral and one mixed, or 42 severe, seven moderate, seven mild APS. Forty-one severe, seven moderate and central APS were all revealed with MDCT and DSA. Seven mild and peripheral APS were all displayed with MDCT; only five of them displayed DSA, two faint shunt APS associated with massive HCC were missed. One mixed APS was demonstrated as severe combined with mild shunt with both MDCT and DSA. CONCLUSION: MDCT could diagnose not only DSA revealed APS, but also missed mild and peripheral APS with DSA due to faint shunt associated with massive HCC, is a simple, effective and noninvasive new technique for diagnosis of HCC-associated APS.     

乙酸灌注兔肝门静脉分支后兔肝组织超声改变的实验研究

观察乙酸灌注兔肝门静脉分支后兔肝组织的二维超声、彩色多普勒、脉 冲多普勒变化。选19只兔,分5组,剖腹后经门静脉右外支注入50％乙酸（按公斤体重）,行彩色多普勒和脉冲多普勒检测,发现灌注区门静脉无血流信号或有极少的血流信号,伴行的肝动脉血流速度明显降低甚至未能测到。认为经门静脉分支灌注乙酸可同时降低或阻断灌注区肝组织的门静脉和肝动脉血供。     

Aneurysms of digestive arteries. What are the indications?

Twelve cases of visceral artery aneurysms have been retrospectively reviewed in order to evaluate the results of the various therapeutic decisions. Aneurysms were located on splenic (n = 5), hepatic (n = 1), celiac (n = 3), superior mesenteric (n = 1), pancreatico-duodenal arteries (n = 1) and superior mesenteric artery branches (n = 2). Among two patients operated on for ruptured aneurysms, one patient who suffered from free intraperitoneal hemorrhage died after the operation. All patients operated on with unruptured aneurysms survived. Among two patients who were not operated on because of the small size of the aneurysms, one died suddenly a few years later from an unknown cause which may have been a rupture, and the second one was lost from the survey. Our results and those in the literature suggest that surgical treatment (or in some cases percutaneous embolization) is indicated in any symptomatic aneurysm and in most asymptomatic aneurysms except in splenic artery aneurysms. The latter should be operated on only when the diameter is more than 2.5 cm or when they are found in pregnant women or in women with child-bearing capacity.     

IgA and its different molecular forms in the mesenteric, portal and peripheral venous blood in man

The aim of this study was to assess the role of mesenteric blood in polymeric IgA (p-IgA) and IgA2-transport from the intestinal mucosa into plasma and the role of the liver in the clearance of these molecular forms of IgA. The concentrations of IgA, p-IgA and IgA2 were measured in mesenteric, splenic, portal, and hepatic veins of 7 control subjects without liver disease and in portal and peripheral veins of 4 patients with alcoholic cirrhosis. In control subjects, the concentration of the different molecular forms of IgA were not significantly different in mesenteric and in splenic vein. No significant decrease of IgA concentrations was observed in hepatic vein, as compared with portal vein. In cirrhotic patients IgA concentrations were significantly higher than in control subjects, but concentrations of IgA, p-IgA and IgA2 were not different in portal and peripheral blood. These results show that mesenteric vein is not a major way for p-IgA and IgA2 from the gut lamina propria to plasma, and suggest that the origin of a significant part of these molecular forms of IgA could be peripheral lymph-nodes more than gut-associated-lymphoid-tissue. The absence of significant clearance of p-IgA by the liver in normal subjects suggests that abnormalities of hepato-biliary transport of p-IgA is not responsible for the increased IgA levels observed in cirrhotic patients.     

Immunological characteristics of cells entering the liver with portal blood

The mononuclear cell populations were characterized phenotypically and functionally in the splenic, mesenteric, portal, sinusoidal, and hepatic venous blood. We found higher concentrations of mononuclear cells in splenic than mesenteric and portal blood; splenic blood contained high numbers of cells with Fc, C3b receptors and surface immunoglobulin and OX8+ (cytotoxic/suppressor) cells. Liver sinusoidal blood was enriched, compared with inflowing portal blood, in cells with Fc, C3b receptors and surface immunoglobulin, OX+8 cells, and natural killer and killer cells. These findings indicate that the spleen may be the main source of migrating streams of cells to the liver and that cytotoxic subsets of these cells are retained in that organ.     

Carbon dioxide‐based portography: An alternative to conventional imaging with the use of iodinated contrast medium

Background and Aim: To clarify the efficacy of carbon dioxide (CO₂) as a contrast material to evaluate portal vein images by percutaneous transhepatic portography (PTP). Methods: Twenty patients (38–76 years; male 13, female 7) with chronic liver diseases were the subjects of this prospective study. Portal venous opacification by PTP was compared between CO₂‐based images and iodinated contrast medium (ICM)‐based images by two independent reviewers, according to the three‐grade scoring; 0 for none, 1 for weak and 2 for sufficient. Results: Total scores of extrahepatic portal veins (137 for CO₂, 93 for ICM), collateral vessels (64 for CO₂, 60 for ICM) and intrahepatic portal veins (69 for CO₂, 76 for ICM) were not statistically significant between CO₂‐based and ICM‐based images (P = 0.0623). Sufficient opacification of superior mesenteric vein was more frequent on CO₂‐based images (none 0, weak 4, sufficient 16) than ICM‐based images (none 19, weak 0, sufficient 1; P < 0.0001). The score was not statistically significant between CO₂‐based and ICM‐based images in portal trunk, splenic vein, inferior mesenteric vein and other collateral vessels. Although opacification grade in the intrahepatic left portal vein was not statistically significant between CO₂‐based and ICM‐based images (P = 0.1515), weak opacification was significantly frequent on CO₂‐based images (weak 10, sufficient 10) compared to ICM‐based images (weak 0, sufficient 20; P = 0.0003) in the intrahepatic right portal vein. Inter‐reviewer agreement was excellent between the two reviewers for CO₂‐based images (kappa = 0.913) and ICM‐based images (kappa = 0.924). Conclusions: Carbon dioxide may be a first‐line contrast material for evaluating portal vein images by PTP.