首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
OBJECTIVE: To determine whether the hepatovenous intrahepatic anastomoses exist in normal humans. METHODS: A total of 13 livers were isolated during the early autopsies of normal men who died in accidents. Perfusion venography of the branches of hepatic veins using meglucamine diatrizoate was performed in 6 cases. This method of investigation has not been reported in the literature. In one case, a portal venography was done. In the remaining 6 cases, liver substance stainings were done by injecting ink through the middle hepatic vein, and the tissue sections of these livers were observed under light microscope. RESULTS: There were intrahepatic anastomoses between the hepatic veins within the liver. These anastomoses belonged to the 4th or 5th branch of hepatic vein near the capsule. There were also anastomoses between the middle hepatic vein and the hepatic short veins. Shunts existed between the portal veins and hepatic veins. CONCLUSIONS: The detection of anastomoses of intrahepatic veins in normal individuals provide anatomical rationale for the performance of irregular hepatectomy, as well as rationale for the ligation of one or two hepatic veins should such veins be traumatized or invaded by liver cancer.  相似文献   

2.
Unique spiral structures, located in the wall of the hepatic venous system in the dog, were examined in the central veins and the hepatic venous branches, utilizing microvascular corrosion casting and freeze-fracture technique in scanning electron microscopy and transmission electron microscopy of tissue sections. The whole hepatic venous system was divided into 4 portions: the central, sublobular, collecting and branches of the hepatic veins. The central vein was spindle-shaped with several compressions. Removing the endothelial cells of the central vein, pathways of venous sinusoids were like a labyrinth. In the sublobular veins, spiral structures distinctly appeared as the diameter increased. Beneath the endothelial cells in the constricted portions, smooth muscle bundles were found. The spiral structures gradually became irregular in the collecting veins and discontinuous to form shallow constrictions in cast thicker branches of the intrahepatic veins. A single, fine spindle of the central vein was formed by the arrangement of liver cells. The spiral structures of the sublobular vein were formed by smooth muscle bundles. Irregularity of the spiral structures in the collecting veins was caused by smooth muscle bundles anastomosing with adjacent ones. Disappearance of the spiral structure in cast thicker branches of the intrahepatic veins was due to absence of muscle bundles.  相似文献   

3.
Budd-Chiari syndrome (BCS) due to membranous obstruction of the hepatic vein and the inferior vena cava is rare in children. We report a child with BCS that had a membranous obstruction at the level of the hepatic veins. The web was successfully dilated percutaneously by balloon catheters. Symptoms and signs of obstruction improved without any complication. As percutaneous catheterization is an effective, safe and repatable procedure, we recommend this technique for treatment of children and adults with BCS due to membranous obstruction of the hepatic veins.  相似文献   

4.
OBJECTIVE: Changes in the Doppler waveform of the hepatic veins are associated with chronic liver disease, particularly cirrhosis. We correlated abnormalities in Doppler waveforms of hepatic veins with histologic findings in the liver to determine the accuracy of Doppler imaging in the detection of cirrhosis. SUBJECTS AND METHODS: Fifty-two patients with chronic hepatitis C were examined prospectively and blindly by two sonographers. In the same session, a liver biopsy specimen was obtained from each patient and submitted to three independent pathologists for conventional interpretation and for grading of severity according to a predetermined scoring system. Duplex sonography of the hepatic veins was also performed in 50 control subjects. RESULTS: Abnormal hepatic vein waveforms were detected in 12 of 16 patients with cirrhosis and in eight of 36 patients without cirrhosis. However, histologic examination of the biopsy specimens showed that only two of the eight patients without cirrhosis had no significant abnormalities, other than mild portal inflammation. Abnormal waveforms were seen in no control subjects. We found a correlation between fibrosis and steatosis and abnormalities in the Doppler waveform of the hepatic veins (r = .50, p < .001). Portal inflammation, intralobular degeneration, and necrosis did not correlate with an abnormal waveform. CONCLUSION: Duplex sonography of the hepatic veins may be useful for studying liver disease associated with fibrosis and steatosis. In patients with well-compensated liver disease, flattening of the Doppler waveform of the hepatic vein suggests the presence of cirrhosis.  相似文献   

5.
The purpose of this study is to identify the existence of hepatovenous intrahepatic anastomosis in normal men. A total of thirteen livers were investigated during the early autopsies of normal men who died in accidents. Perfusion venography of branches of hepatic veins using meglucamine diatrizoate was done in six cases; this method we used had not been reported in the literature. In one case, portal venography was performed. And in the other six cases, liver substance staining was done by injecting the ink through the middle hepatic vein, and such staining of the liver was observed by light microscope. The results show, (1) there are intrahepatic anastomoses between the hepatic veins within the liver; (2) there are anastomoses between the middle hepatic vein and the accessory hepatic veins; and (3) shunts exist between portal veins and hepatic veins. The above findings provide an anatomical basis for the performance of irregular hepatectomy and the rationale for one or two hepatic veins ligation should such veins were traumatized or invaded by liver cancer.  相似文献   

6.
In gross anatomic and angiographic examinations of the hepatic veins of 15 goats, the following were seen: (i) The middle hepatic vein was formed by the contribution of two main branches, one branch coming from the quadrate lobe and the other branch from the right lobe. (ii) There were two right hepatic veins, one of them running along the caudate process and the other formed by branches coming from the dorsal part of the right lobe. (iii) The entrance of the middle hepatic vein, as well as the entrance of the left hepatic vein into the caudal vena cava were partly covered by valvelike membranous flaps.  相似文献   

7.
BACKGROUND/AIMS: Complete intermittent vascular exclusion of the liver (IVEL) combines clamping of the hepatic pedicle with clamping of the hepatic veins without interruption of the caval flow. The major advantages of this technique are that patient preclamping fluid overload is avoided, major haemodynamic changes due to caval clamping are escaped, and it allows a very long clamping time. Disadvantage of this technique is the necessity of looping the terminal part of the hepatic veins. METHODOLOGY: In this prospective study, 41 cases of IVEL (Representing 19% of the hepatectomies carried out for cancer during the same period) used for difficult hepatectomies were analyzed, and the operative technique is presented. RESULTS: IVEL was feasible in 90% of the 46 attempted cases, and completely controlled the bleeding in 90% of the cases. The mean duration of IVEL was 69.2 minutes (Range: 37 to 140), and was greater than 130 minutes in three patients. No liver failure occurred during the postoperative course. CONCLUSION: We conclude that IVEL without caval clamping is a new, and valuable, technique of vascular exclusion of the liver. Its application is indicated in the following conditions: 1. For patients who should have classical vascular exclusion but cannot tolerate vena cava clamping (18% of the cases), 2. for patients with pathological liver parenchyma when intrahepatic venous pressure is high, 3. for patients with impaired liver parenchyma, requiring conservative surgery that leads to anatomic or non-anatomic resection close to a vein (Example: A tumor located in the dihedral angle of the terminal part of two hepatic veins), 4. for patients with tumors closely located to a hepatic vein that must be preserved and sharply dissected (Example: A left trisegmentectomy that requires pelting of the right hepatic vein), and 5. for the scarce patient with tumors infiltrating the major hepatic veins, constraining a hepatic vein reconstruction to preserve liver function.  相似文献   

8.
The blood flow in the hepatic veins can normally be studied easily by Doppler ultrasound. The pattern of blood flow in normal individuals is described, and its relation to the cardiac cycle and changing pressure in the right atrium. The blood flow shows variations in healthy persons, and may change in cases of heart disease and hepatic disease. Conditions such as atrial fibrillation, tricuspid regurgitation, abnormal relaxation, restrictive cardiomyopathy, constrictive pericarditis and cardiac tamponade are reflected in the hepatic veins, and the pattern of blood flow may help in diagnosis, and in grading the pathology. In cirrhosis and portal hypertension the heart-synchronous variation in velocity is reduced. This is due to increased resistance to blood flow across the liver and the pressure gradient becoming larger than the variations in pressure in the right atrium.  相似文献   

9.
The hepatic arterial and hepatic portal venous vascular beds of the chloralose-urethane anesthetized dog were perfused simultaneously in situ. Vasopressin (10 mU = 1 unit) was injected in graded increasing doses into the hepatic artery and into the portal vein. Both intra-arterial and intraportal vasopressin elicited both hepatic arterial vasoconstriction and hepatic venous dilation; the delay in onset of both hepatic vascular effects was significantly shorter than that for any succeeding systemic effects (a rise in systemic arterial pressure and fall in heart rate), showing that they were not attributable to recirculation or to arterial baroreceptor reflexes. Injections of vasopressin into the inferior vena cava at the level of the hepatic veins consistently produced smaller hepatic vascular effects than either intra-arterial or intraportal injections of the same doses. The results are discussed in the context of the therapeutic role of vasopressin in controlling gastrointestinal bleeding and portal hypertension.  相似文献   

10.
BACKGROUND: The clinical pattern and long-term course of chronic inferior vena cava (IVC) obstructions are variable and depend on the underlying cause, the segment involved, and the extension of secondary thrombosis. Pertinent data on IVC obstructions in well-defined series of patients are lacking. We report the sequelae of chronic IVC obstructions in the hepatic segment in 11 consecutive patients derived from a cohort of 104 patients with alveolar echinococcosis of the liver. METHODS: Based on the results of computed tomography scans, 11 patients (7 men, 4 women; mean age, 53.4 years) with IVC obstructions were selected from an ongoing prospective long-term chemotherapy trial comprising 104 patients with alveolar echinococcosis studied at yearly intervals according to a protocol. Obstruction of the IVC in the 11 patients existed for a mean duration of 8.6 years. In these patients, magnetic resonance imaging was performed to assess the morphologic features and extension of the IVC obstruction, as well as the collateral venous pathways. Patency and valvular function of the femoropopliteal veins were analyzed by color-coded duplex ultrasonography. RESULTS: Total occlusions of the IVC were evident in 8 patients (73%) and subtotal stenoses in 3 patients (27%). Only 4 patients (36%) exhibited signs and symptoms of chronic venous insufficiency of the lower extremities; 2 (18%) of the 4 had a history of swelling in the lower extremity. Seven patients (64%) had no lower extremity symptoms. One patient had a history of pulmonary embolism. Abdominal collateral veins were documented in 5 patients (45%) by using magnetic resonance imaging; however, they were clinically evident in only 3 patients (27%). In the 8 patients with IVC occlusion, thrombosis ended at the confluence of the hepatic veins. Obstruction of the IVC was limited to the hepatic segment in 2 patients (18%) and extended to the distal IVC or the iliofemoral veins in 6 patients (54%). Chronic venous insufficiency was present only if the femoropopliteal veins had been involved in the thrombotic process, showing residual venous obstruction, valvular incompetence, or both. Bilateral renal vein thrombosis with moderate proteinuria was observed in 2 patients (18%). The main collateral drainage was achieved through the ascending lumbar, azygos, and hemiazygos veins. CONCLUSIONS: In patients with alveolar echinococcosis, obstruction of the IVC in the hepatic segment often develops asymptomatically and rarely leads to the impairment of renal function. The collateral circulation fully compensates for obstruction of the IVC. Thrombotic involvement and valvular incompetence of the femoropopliteal veins seems to determine the development of chronic venous insufficiency of the lower extremities.  相似文献   

11.
Injuries to the hepatic veins and retrohepatic vena cava have a high mortality due to uncontrolled hemorrhage. Successful repair may necessitate interruption of flow through the retrohepatic vena cava. Active bypass of the area is then needed to provide adequate venous return. Published methods for active bypass require cannulation of axillary and femoral veins in addition to clamping of the vena cava above and below the liver, often with limited exposure and significant risk. This report describes active bypass of the retrohepatic vena cava utilizing two right atrial cannulae. The simplicity of establishing the bypass together with the excellent exposure allowed repair of a bullet wound of the vena cava in one patient and the orderly performance of a left trisegmentectomy for a huge hepatic tumor in a second patient.  相似文献   

12.
Budd-Chiari syndrome (BCS) was initially defined as a symptomatic occlusion of the hepatic veins, but subsequent reports on various obliterative changes that occur in the hepatic portion of the inferior vena cava (IVC) and hepatic vein orifices have resulted in a broadened and ambiguous definition. Membranous obstruction of the inferior vena cava has been regarded by many as a congenital vascular malformation, but its relation to the classical BCS has remained obscure. With modern imaging and recent histological study of new cases, membranous obstruction of the IVC is now considered to be a sequela to thrombosis. How to classify various forms of occlusion and stenosis of the IVC and hepatic vein ostia is a major challenge. In this review, we emphasize that primary hepatic vein thrombosis (classical Budd-Chiari) and an obliterative disease predominantly affecting the hepatic portion of the IVC, both of which account for most patients with venous outflow block, are clinically quite different. In the West, the former is more common than the latter, which constitutes the vast majority of cases of outflow block in developing countries such as Nepal, South Africa, China, and India. The latter is frequently complicated by hepatocellular carcinoma (HCC), and primary hepatic vein thrombosis is not. The major cause of thrombosis is a hypercoagulable state in hepatic vein thrombosis, but more of the latter cases are idiopathic. The clinical presentation of the latter is milder, and onset is frequently inapparent, whereas the former is more severe, sometimes causing acute hepatic failure. Markedly enlarged subcutaneous veins over the body trunk characterize the latter. We propose that these two disorders be clinically distinguished with a suggested term "obliterative hepato-cavopathy" for the latter against classical BCS.  相似文献   

13.
OBJECTIVE: The objective of this paper is to describe a new finding on CT of hepatic and portal vein segments located in a subcapsular location on the surface of the liver. SUBJECTS AND METHODS: From a series of more than 11,000 contrast-enhanced abdominal CT scans performed from 1993 to 1997, 14 patients were identified as having hepatic or portal vein segments or both in a subcapsular location on the surface of the liver. RESULTS: We found seven portal vein surface segments in seven patients and 14 hepatic vein surface segments in 12 patients. Of the 14 patients, five had both portal and hepatic vein surface segments. Therefore, in a cohort that exceeded 11,000 patients, the incidence of this finding was 0.1%. Four patients had cirrhosis, two had small hypervascular liver lesions, and eight had healthy livers. The surface veins were not associated with any other recognized vascular anomalies or with anastomoses to extrahepatic systemic veins. CONCLUSION: Hepatic and portal veins can course to a subcapsular location on the surface of the liver. This anatomy is believed to be a normal variant and can be found in patients with healthy livers and normal hepatic vein hemodynamics and in patients with portal hypertension.  相似文献   

14.
The principal aim of this study was to elucidate key features of the inferior phrenic vein (IPV) of adult rats to determine whether the IPV has the potential to function as a collateral return route conveying blood from the lower portion of the body to the heart, bypassing the subhepatic vein segment of the inferior caval vein. In rats, the IPVs on both sides were found to reveal a symmetric appearance. They were both composite vessels, being made up of two fellow subvessels, the sternocostal and the lumbocostal veins, which in turn anastomosed in tandem in their periphery with each other, formed a collateral route bridging the interval between the suprarenal and the hepatic vein segments of the inferior caval vein. In rat embryos of E17.5, the sternocostal and lumbocostal veins of the IPV were observed to have been well developed, forming tandem anastomoses more clearly than in adults, thus connecting the subcardinal vein to the hepatic vein segment of the inferior caval vein. This fact substantiates our supposition that the rat's IPV originally has the potential to act as a collateral returning route which allows blood to bypass the subhepatic vein segment of the inferior caval vein.  相似文献   

15.
BACKGROUND: Hepatic vein outflow is discussed in liver transplantation after preservation of recipient retrohepatic vena cava. The aim of this study was to compare two methods of suparahepatic caval anastomosis. METHODS: From January 1993 to January 1995, 81 patients received 88 liver transplants because of liver cirrhosis (n = 70), acute liver failure (n = 7), elective retransplantation after hepatic artery thrombosis (n = 2), giant hemangioma (n = 1), and combined liver-small bowel transplantation (n = 1). Seven patients underwent urgent retransplantation, 12 had preoperative transjugular intrahepatic portocaval stent, and 11 had portal vein thrombosis. Five patients required extracorporeal venous shunt. A total of 82 liver transplantations had preservation of RHVC, and 70 patients received temporary end-to-side portacaval shunt. Suprahepatic caval anastomosis was carried out in 52 patients (group 1) between the graft suprahepatic vena cava and the ostia of recipient left and median hepatic veins. Thirty patients (group 2) had associated 3 cm vertical cavotomy with partial clamping of RHVC. In the fourth postoperative month 20 patients from each group had pressure and gradient measurement made among the hepatic veins, right atria, and the RHVC. RESULTS: Mean pressure gradient between hepatic veins and right atria was 0.75 +/- 0.49 mm Hg in group 1 and 2.06 +/- 0.85 mm Hg in group 2. Between the RHVC and the right atria it was 0.63 +/- 0.5 mm Hg in group 1 and 2.22 +/- 1.29 mm Hg in group 2. A pressure gradient higher than 3 mm Hg was considered hemodynamically significant. This pressure gradient was found between the hepatic veins and right atria in 10% of patients in group 1 and 40% of patients in group 2 (p = 0.03) and between the RHVC and right atria in 15% of patients in group 1 and 30% of patients in group 2 (p = 0.3). CONCLUSIONS: Preservation of the recipient RHVC with recipient caval anastomosis at the ostia of the median and left hepatic veins is a reliable technique without any hepatic venous outflow alteration. Associated cavotomy is not necessary.  相似文献   

16.
PURPOSE: To compare use of magnetic resonance (MR) imaging and ultrasonography (US) for diagnosis of vascular involvement by tumor at the hepatic vein confluence. MATERIALS AND METHODS: Thirty-seven consecutive patients with tumors at the hepatic vein confluence were prospectively evaluated with spin-echo and gradient-echo MR imaging and gray-scale and Doppler US. Encasement, thrombosis, occlusion, and nonvisualization were considered to be evidence of vascular involvement. Imaging results were compared with surgical and pathologic examination findings in 27 patients who underwent resection. RESULTS: Sixteen hepatic veins (nine right, four middle, three left) were seen to be involved at surgery. Twelve of 16 involved veins were identified at MR imaging (75% sensitivity, 98% specificity, 92% positive predictive value, 94% negative predictive value). Thirteen of 16 involved veins were detected at US (81% sensitivity, 97% specificity, and 87% positive and 95% negative predictive values). There was one false-positive diagnosis of inferior vena cava involvement at both MR imaging and US. Ten patients had unresectable disease. One patient had motion artifact on MR images; in the remaining nine patients, MR imaging and US yielded identical findings at 26 of 27 hepatic vein sites. CONCLUSION: MR imaging and US provide comparable results for assessment of hepatic vein involvement by tumor.  相似文献   

17.
To determine the absorption and metabolism of 17 beta-estradiol (E2) by the stomach and liver of the pig, crystalline E2 was placed in the stomach of prepubertal gilts. Blood samples were subsequently obtained from the hepatic portal and jugular veins and plasma was assayed for E2, estrone (E1), 17 beta-estradiol-glucuronide (E2G), estrone-glucuronide (E1G) and estrone-sulfate (E1S). Concentrations of E2, E1, E2G and E1S rose in the hepatic portal vein within five min and remained elevated for several hr. Concentration of E2 represented only 6% of the total estrogen detected in the hepatic portal vein during the sampling period, indicating that most of the E2 was converted or conjugated prior to entering the hepatic portal vein. The metabolism of E2 presumably occurred in the stomach mucosa because food had been withheld for 26 hr before infusion of E2. Concentrations of E2G, E1G and E1S, but not E2 and E1, rose in the jugular vein and remained elevated for several hr. The lack of a rise in E2 and E1 in the jugular vein indicates that the E2 and E1 from the hepatic portal vein were completely converted and/or removed by the liver. Most of E2 was converted to E1 and then to E1G. The infusion of bile containing normal estrogens from pregnant gilts into the duodenum of prepubertal gilts resulted in a peak of E1G and E2G in the hepatic portal and jugular veins within a few minutes. This was followed in about 180 min by a second sustained rise. The first peak was essentially abolished by extracting E1 and E2 from the bile before infusion. The second peak failed to occur in gilts given antibiotics orally to reduce gut bacteria before infusion of bile.  相似文献   

18.
Hepatic occlusion venography with the aid of a Swan-Ganz balloon catheter represents a significant improvement in the radiographic demonstration of hepatic veins and their alteration in liver disease. It is simple to perform and can be combined with other hemodynamic examinations (e.g., hepatic vein pressure measurements). In this way the morphologic and hemodynamic changes in the pre- and postoperative evaluation of patients with portal hypertension can be investigated simultaneously. The method allows optimal demonstration of large branches of hepatic veins. Overloading of small areas of liver parenchyma with concentrated contrast medium, as in wedged hepatic venography, is avoided. Previously unknown portosplanchnic anastomoses developing after end-to-side portacaval shunt were demonstrated in seven of eight patients using this method. The frequency and size of these collaterals suggest possible hemodynamic and clinical significance.  相似文献   

19.
BACKGROUND/AIMS: To preserve remnant liver function, extended left hepatectomy combined with middle hepatic vein reconstruction using a left renal vein graft was performed in resection of liver metastasis from sigmoid colon cancer, involving the confluence of the middle and left hepatic veins. METHODOLOGY: The tumor, 5 cm in size, occupied the superior part of segment 4, and involved the confluence of the middle and the left hepatic veins. An extended left hepatectomy, including the left lobe, left caudate lobe and part of segment 8, together with the middle hepatic vein trunk, was performed. The left renal vein was resected as a graft from the confluence of the inferior vena cava just distal to the branches of the gonadal vein, renal-azygos, splenorenal communications and vertebral veins. The middle hepatic vein was reconstructed using the left renal vein 3 cm in length. RESULTS: Impaired values of liver function tests were normalized by the third postoperative day. Renal function was good throughout the postoperative period. The patient was discharged two weeks after the surgery. The reconstructed middle hepatic vein was patent, which was evaluated by a color Doppler ultrasonography, computed tomography and magnetic resonance imaging 60 days after the surgery. The patient remained well in the eight months thereafter. CONCLUSIONS: Hepatic vein reconstruction using a left renal vein graft is a new and preferable addition for the selection of an optimal graft.  相似文献   

20.
We report a case of Budd-Chiari syndrome following repair of a giant omphalocele. Thrombosis of hepatic veins and of retrohepatic inferior vena cava may result from direct pressure on the hepatic venous outlet after visceral reduction and final abdominal wall closure.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号