AUTHOR AND EDITOR INFORMATION

Section 1 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

INTRODUCTION

Section 2 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Background

Budd-Chiari syndrome (BCS) is a manifestation of hepatic venous outflow obstruction that was first described by Budd in 1845 and then expounded upon by Chiari, who presented 13 cases in 1899. The hepatic outflow obstruction usually occurs at the level of the inferior vena cava (IVC); the hepatic veins; and, depending on the classification and nomenclature, possibly at the venule level.

The causes of BCS are numerous. There are 2 types of BCS: acute and chronic. The acute form results from an acute thrombosis of the main hepatic veins or the IVC. The chronic form is related to fibrosis of the intrahepatic veins, presumably related to inflammation. The classic presentation is with ascites, hepatomegaly, and abdominal pain.

Pathophysiology

In BCS, hepatic venous occlusion causes increased sinusoidal pressure, leading to a delay or reversal of portal venous blood inflow, ascites, and morphologic changes in the liver (resulting in abnormal liver function test results). Both the acute form and the chronic form of BCS result in severe centrilobular congestion and hepatocellular necrosis and atrophy. Two diseases that have clinical characteristics similar to those of BCS are severe right-sided heart failure and veno-occlusive disease of the liver. Hepatic veno-occlusive disease is characterized by inflammation of the postsinusoidal venules, which results in fibrosis and venous occlusion.

Membranous obstruction of the inferior vena cava (MOVC) is a rare clinical entity. The incidence of MOVC is higher in Japan and in Africa than it is in the United States and Europe. MOVC is a curable cause of a primary type of BCS, but MOVC is different from BCS in clinical manifestation and pathologic changes in the liver. Most patients with MOVC are cirrhotic and have ascites and esophageal varices.¹ 

BCS has been variously classified, with some investigators distinguishing between primary BCS (associated with IVC webs) and secondary BCS (ascribed to numerous causes, including tumor, thrombosis, and trauma). Still other authors categorize the disease according to the location of the obstruction, as follows:

• Type I disease - Occlusion of the IVC with or without secondary hepatic vein occlusion
• Type II disease - Occlusion of major hepatic veins
• Type III disease - Obstruction of the small centrilobular venules (considered by some authors as veno-occlusive disease)

The causes of BCS are numerous and include the following:

• Idiopathic: Historically, most cases of BCS considered idiopathic or congenital, although recent studies suggest the cause is unknown in only one third of cases
• Congenital: BCS caused by web, diaphragm, interruption of the IVC
• Venous thrombosis: BCS resulting from polycythemia rubra vera, antiphospholipid syndrome, pregnancy and the postpartum state, use of oral contraceptives, sickle cell disease, thrombocytosis, paroxysmal nocturnal hemoglobinuria
• Injury and/or inflammation: BCS caused by phlebitis, autoimmune disease (Behçet disease), trauma, radiation injury, use of immunosuppressive drugs and pyrrolizidine alkaloids
• Liver pathology: Fibrosis, hemorrhage, congestion causes of BCS
• Tumor: BCS caused by renal cell carcinoma, hepatocellular carcinoma, adrenal carcinoma, metastasis, leiomyosarcoma of the IVC

In most patients with BCS, hepatic venous outflow is not completely eliminated because accessory hepatic veins drain into the IVC above or below the site of obstruction. The most common accessory veins include the accessory inferior hepatic and caudate veins, which drain into the IVC inferior to the major hepatic veins. Vascular communications also exist via the azygos vein, the intercostal vessels, and the paravertebral veins, which provide alternative pathways for hepatic venous drainage in patients with BCS.

Intrahepatic communication between the hepatic and portal veins also establishes reversal of flow in some of the portal venous branches, although flow in the main portal vein tends to remain centripetal. Some of the hepatic venous drainage is preserved; the caudate lobe hypertrophies, sometimes massively, and it may produce secondary IVC obstruction. Other parts of the liver that have preserved venous drainage may also undergo hypertrophy.

Some venous drainage also occurs via the capsular veins, but this drainage is not sufficient to prevent peripheral atrophy in patients with BCS. Parts of the liver that have complete obstruction of venous drainage tend to drain via the portal vein branches, depriving involved parts of the liver of a portal venous blood supply; therefore, the trophic effects of hormones occur. Hepatic hypertrophy and regeneration always depend on the trophic effect of the portal blood supply. Thus, BCS typically is associated with peripheral atrophy of the liver and with caudate and central hypertrophy. On cross-sectional images, the porta hepatis may be displaced anteriorly in BCS. Concomitant portal vein thrombosis may be present in 9-20% of patients with BCS.²

Frequency

United States

Hematologic disorders, such as polycythemia rubra vera, paroxysmal nocturnal hemoglobinuria, and myeloproliferative diseases, account for 18% of the cases of BCS. A history of pregnancy or the postpartum state accounts for another 20%. Tumors account for 9%, while IVC webs account for most cases in patients from eastern Asia, India, and South Africa. Veno-occlusive disease is a complication in as many as 25% of patients treated with bone marrow transplantation.

International

Overall incidence of BCS is unknown.

Mortality/Morbidity

BCS is potentially life-threatening, depending on the extent and rapidity of hepatic venous obstruction. A high index of suspicion is necessary in order to make the diagnosis, because BCS can be very indolent or even asymptomatic.

• Prognosis is more favorable in patients with IVC webs but is extremely poor in patients with renal cell carcinoma, hepatocellular carcinoma, and adrenal tumors.
• Mortality is 83% in patients with veno-occlusive disease, but if BCS is diagnosed early, patients may respond to treatment such as anticoagulant therapy.
• Treatment procedures are high risk and are associated with different rates of morbidity and mortality.
• In a multicenter international investigation, Murad et al studied the determinants of survival and evaluated the use of portosystemic shunting in 237 patients with BCS.³. Overall survival at 1 year, 5 years, and 10 years was 82% (95% confidence interval [CI], 77-87%), 69% (95% CI, 62-76%), and 62% (95% CI, 54-70%), respectively. Independent determinants of survival were encephalopathy, ascites, prothrombin time, and bilirubin level. At the time of diagnosis, patients were classified into 3 prognostic classes on the basis of baseline clinical and laboratory parameters: good prognosis, class I; intermediate prognosis, class II; and poor prognosis, class III. The 5-year survival rate for BCS patients in class I was 89% (95% CI, 79-99%); for class II, 74% (95% CI, 65-83%); and for class III, 42% (95% CI, 28%-56%). Anticoagulants were given to 72% of patients, but this treatment improved survival only in class I patients (relative risk [RR], 0.14; 95% CI, 0.02-1.21). Portosystemic shunting was performed in 49% of the patients (n = 117). Improved survival with surgical portosystemic shunting occurred in class II BCS patients; time-dependent analyses showed improved survival only in these patients (RR, 0.63; 95% CI, 0.26-1.49). 
  

Race

The IVC web/diaphragm, believed to be either congenital or an acquired abnormality from long-standing IVC thrombosis, is a common cause of BCS in South Africa, India, Japan, and Korea but is rare in Europe and North America.

Sex

A slight female preponderance is seen in patients with BCS.

Age

Persons of any age can be affected, although hepatic veno-occlusive disease after bone marrow transplantation is more a disease of the young than a disease of older individuals.

Anatomy

Superior veins (right, middle, left) drain most of the liver. Typically, the superior veins are as large as 1 cm in diameter and pass obliquely back and upward to the IVC. Small veins drain the caudate and adjacent part of the right lobe directly to the IVC. Separate caudate lobe venous drainage may allow preservation of caudate lobe function in hepatic vein obstruction.

Flow in the hepatic veins is complex because it is affected directly by flow and pressure changes in the right atrium and IVC. Throughout the greater part of the cardiac cycle, flow is toward the heart (ie, away from the ultrasound [US] probe on the anterior abdominal wall). Forward flow toward the heart is reduced during right atrial systole as the pressure of right atrial contraction is carried back to the IVC and hepatic veins.

After right atrial systole, a brief increase in hepatic vein flow occurs, followed by a pressure wave caused by sudden tricuspid valve closure at the start of ventricular systole. The pressure wave caused by tricuspid closure may result in transient reversal of normal hepatic vein flow. The reversal of flow indicates that the liver is soft and compliant and can accommodate transient flow reversal.

Hepatic parenchymal disease may increase hepatic rigidity, reducing compliance and preventing flow reversal. A rough correlation exists between the degree of flattening of the hepatic vein waveform and the degree of severity of hepatic parenchymal disease. Cardiac disease may affect the hepatic venous waveform, usually increasing the waveform pulsatility, but the effect depends on the nature of cardiac disease and the presence or absence of hepatic parenchymal disease.

Hepatic disease that increases hepatic rigidity reduces the effect of cardiac disease on the hepatic venous waveform. Prolonged or sudden severe IVC or hepatic venous congestion may cause hepatomegaly and jaundice. When the hepatic parenchyma is abnormally rigid, abnormal cardiac waveforms may be masked by reduced hepatic compliance.

Maximum diameters of the main trunk right hepatic vein are 6.2 mm ± 1.43 in healthy men and 5.6 mm ± 1.66 in healthy women.

Clinical Details

• Patients present with painful hepatomegaly and diuretic-resistant ascites.
• Features of portal hypertension and variceal bleeding occur later.
• Approximately 25% of patients with BCS present acutely, and the remainder of patients present with subacute or chronic disease.
• In addition to abdominal pain, patients also may present with lower limb edema and distended abdominal veins.
• Splenomegaly and jaundice are recorded in as many as 25% of patients.
• In the less common acute form, rapid onset of abdominal pain, vomiting, hepatomegaly, and jaundice occur, often in the setting of a known renal or hepatic tumor or the setting of bone marrow transplantation and a patient on chemotherapy.
• Biochemical findings include elevation of transaminase and serum alkaline phosphatase levels with only a slight elevation of bilirubin levels. The prothrombin time may be prolonged.

Preferred Examination

On the whole, plain radiography has little to offer in the diagnosis of BCS.

Sonography is noninvasive and has high sensitivity and specificity. Sonographic images easily depict the echogenic membrane or fibrous cord in the IVC, which is a common cause of chronic BCS.

CT scanning and MRI are making inroads, but diagnostic features are seen in only a minority of patients, although the cross-sectional images are superior and are vital in planning intervention.

Radionuclide scanning is an elegant and noninvasive technique; however, its findings are nonspecific.

Angiography, although invasive, is the criterion standard. This examination may have to be performed, particularly in patients in whom an IVC abnormality is suspected and when radiologic intervention is planned.

The key imaging findings in BCS, including those of CT, MRI, US, and angiography, are occlusion of the hepatic veins, the inferior vena cava, or both; caudate lobe enlargement; inhomogeneous liver enhancement; and the presence of intrahepatic collateral vessels and hypervascular nodules. Awareness of these findings is important for early diagnosis and appropriate treatment.⁴

Limitations of Techniques

All findings from cross-sectional imaging are nonspecific. Both false-positive and false-negative diagnoses may occur, although this limitation applies less to angiographic studies than to other tests.

DIFFERENTIALS

Section 3 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Other Problems to Be Considered

Cirrhosis: Distinguish primary BCS from cirrhosis. Patients with BCS usually present acutely and have larger livers without the nodularity seen in cirrhosis. The cirrhotic liver is often small and nodular with a heterogeneous texture; this is usually associated with extrahepatic collateral varices.

Hepatic veno-occlusive disease: Distinguish BCS from hepatic veno-occlusive disease, which is manifested in the clinical setting of bone marrow transplantation and in patients on chemotherapy. The disease involves diffuse obliteration of postsinusoidal venules. The IVC and major hepatic veins are usually patent.

Heart failure: Right-sided heart failure can usually be distinguished clinically. On images, particularly MRIs and CT scans, hepatic venous congestion is depicted as a heterogeneous mosaic-like distribution of the contrast agent after a dynamic injection.

RADIOGRAPH

Section 4 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Findings

Plain radiography has little to contribute to the diagnosis of BCS.

• Features of ascites, hepatosplenomegaly, and causes of BCS (eg, hepatocellular carcinoma with calcification or renal cell carcinoma with calcification) may be depicted.
• Calcification within a thrombosed hepatic vein is unusual.
• When associated with concomitant portal vein thrombosis, calcification may be seen in the portal vein after prolonged portal hypertension. Portal vein calcification is typically linear or strandlike and lies transversely across the upper abdomen or slopes upward and obliquely toward the liver hilum.
• Esophageal varices can be seen as lobulated posterior mediastinal masses in 5-8% of patients.
• Silhouetting of the descending aorta and an abnormal convex contour of the azygos-esophageal recess are further signs of portal hypertension.
• Varices, if present, can be confirmed on an upper GI barium series.

Degree of Confidence

Most plain radiographic findings have low sensitivity and are nondiagnostic.

False Positives/Negatives

The causes of ascites, portal hypertension, and hepatosplenomegaly are legion and cannot be separated on the basis of plain radiographic findings.

CT SCAN

Section 5 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Findings

• Contrast-enhanced CT findings in patients with BCS include an inhomogeneous mottled liver with delayed enhancement in the periphery of the liver and around the hepatic veins.
• The peripheral zones of the liver may appear hypoattenuating because of reversed portal venous blood flow, which results from increased postsinusoidal pressure produced by hepatic venous obstruction.
• The caudate lobe is enlarged and demonstrates increased contrast enhancement compared with the remainder of the liver.
• Identification of hepatic veins may fail.
• Thrombosis within the hepatic veins and the IVC can be identified in 18-53% of patients.²

Degree of Confidence

Although CT appearances of BCS are nonspecific, certain features, such as thrombosis within the hepatic veins and the IVC, can be identified in 18-53% of patients.² These features are diagnostic of BCS when they are seen in the appropriate clinical setting. Specific sensitivity and specificity rates of CT scans in the diagnosis of BCS have not been defined.

False Positives/Negatives

When spiral CT scans are being interpreted, it is important not to confuse nonopacified hepatic veins and IVC with hepatic venous occlusion, especially in patients with portal hypertension, in whom enhancement of hepatic veins may be delayed.

Causes of an enlarged caudate lobe (caudate lobe hypertrophy) include the following:

• Cirrhosis of any kind: Cirrhosis often has companion findings of right or left lobar atrophy, irregular lobular liver contour, ascites, and varices. In cirrhosis and other causes of a shrunken liver, relative sparing of the caudate lobe often occurs, so that the caudate lobe looks large in relation to the remaining liver.
• Hepatic venous occlusion in which venous drainage from the caudate lobe to the IVC is maintained by emissary veins: The caudate lobe is spared. An enlarged caudate lobe may narrow the intrahepatic portion of the IVC.
• Focal mass lesions within the caudate lobe: Lesions such as cysts, abscess, or neoplasm may enlarge the caudate lobe. Fatty infiltration confined to the caudate lobe may mimic a tumor. Traumatic fractures of the caudate lobe may occur but are rare. Inhomogeneous contrast enhancement may occur in cirrhosis, diffuse liver metastasis, and hepatitis.

MRI

Section 6 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Findings

On MRIs, findings of BCS may manifest themselves as regional differences in signal intensity because of varying perfusion, atrophy, hypertrophy, necrosis, and differences in the amount of intracellular fat or iron.

• The liver parenchyma appears inhomogeneous in 64% of patients.
• The atrophic peripheral liver typically demonstrates low signal intensity on T1-weighted images and high signal intensity on T2-weighted images.
• After the administration of an MRI contrast agent, enhancement of the liver periphery is variable.
• In patients with long-standing disease, nodular regenerative hyperplasia is seen as large nodules with increased signal intensity on T1-weighted images and low-to-intermediate signal intensity on T2-weighted images.
• In acute BCS, the peripheral part of the liver often demonstrates decreased enhancement.
• Standard MRI findings reported in patients with BCS include hepatic vein thrombosis, hepatic vein occlusion and narrowing, hepatomegaly, atrophy of the right lobe of the liver, and enlargement of the caudate lobe. IVC abnormalities shown on MRI include diffuse narrowing and focal thrombosis.
• Venous collaterals are readily shown.
• Comma-shaped intrahepatic varices are a characteristic finding that is commonly seen on coronal scans but is not readily appreciated by other modalities.
• Ren et al used MRA with an FBI (fresh blood imaging) sequence to evaluate its validity in the preoperative assessment of 50 patients with suspected BCS after they had been checked by B-ultrasonography.⁵ Two- and three-dimensional FBIs were performed on a 1.5T superconductive MR scanner, and original images were rebuilt using a maximal-intensity projection (MIP) method. Two physicians reviewed all the images before they knew the angiographic results, and the diagnosis obtained with the FBIs was then compared with the results obtained with angiography. The FBI results were the following: a correct diagnosis for 38 patients, an incorrect diagnosis for 1 patient, and 3 missed diagnoses. The diagnostic sensitivity of the FBI in this study was 93%; the specificity, 89%; and the accuracy, 92%. On FBI, the 13 membranous stenoses of the IVC showed a sudden stenosis of the postliver segment of the IVC; the 5 membranousobstructionsofthe IVC  showed  IVC  thickening  and  an absence of blood signals in the posthepatic segment  of  the IVC; the 4 segmental thromboses of the IVC showed abnormal and intermittent signals in the IVC; the 6 simple hepatic vein obstructions showed obstructive hepatic veins; the 6 stenoses of both the IVC and the hepatic veins showed the stenosis of the IVC, the thickening of the hepatic veins, and a compensatory circulation in the liver; and 7 images showed a combination of the IVC thrombosis with stenosis or with the obstruction of 1 or 2 hepatic veins. This study showed that FBI can identify a membranous stenosis and an obstruction and thrombosis of the IVC. It can also demonstrate thickening of the flexural hepatic vein and development of intrahepatic compensatory branches with slow blood flow. FBI can therefore guide the puncturing and opening of the hepatic vein involved in an interventional therapy for BCSpatients.⁵
• In a study by Park et al, MRI and vena cavography were performed on 9 patients with membranous obstruction of the IVC. In 7 patients, the MR findings were retrospectively analyzed and compared with CT findings. The morphologic features of membranous obstruction of the IVC on spin-echo MRI in transverse or sagittal views were a curvilinear soft-tissue membrane in 5 cases and an obliterated lumen of a hepatic segment of the IVC in 4 cases. The lumen below the obstruction revealed flow-related signal in 7 cases, intraluminal thrombus in 1 case, and thrombotic occlusion in 1 case. The hepatic veins were narrow and disoriented without connection to the hepatic segment of the IVC just below the diaphragm. On T2-weighted images, inhomogeneity with high signal intensity was shown more prominently in the hepatic parenchyma in Simson type II or III membranous obstruction. Other findings were hepatosplenomegaly, an enlarged caudate lobe, acirrhoticliver,associatedhepatoma,andthepresenceofvariouscollaterals.⁶
• MRI examinations of 22 patients with pathologically confirmed BCS showed the following⁷:
  
  
  • Thrombosis of 3 hepatic veins in 19 patients (86%) and 2 hepatic veins in 3 patients (14%) patients
  • Spontaneous intrahepatic anastomoses in 5 patients (23%)
  • Ascites in 15 patients (68%)
  • Thrombosis of the inferior vena cava by an enlarged caudate lobe in 6 patients (27%) and external compression of the IVC by an enlarged caudate lobe in 5 patients (23%)
  • Prominent azygos and hemiazygos veins were demonstrated in 7  patients (32%), 6 of whom had thrombosis of the IVC
  • MRI showed hepatomegaly in all patients and enlarged caudate lobe in 18 patients (82%)
  • T1- and T2-weighted MRI images revealed inhomogeneous signal intensity of hepatic parenchyma in 14 patients (64%)
  • T1- and T2-weighted MRI images showed homogeneous signal intensity of hepatic parenchyma in 8 patients (36%)

Degree of Confidence

MRI techniques are noninvasive and provide excellent multiplanar imaging. Blood vessels can be depicted both with and without the administration of contrast agents. However, unlike US, MRI has limited availability, and the procedure is expensive. The exact sensitivity and specificity of MRI in the diagnosis of BCS are unknown.

False Positives/Negatives

Primary BCS must be distinguished from cirrhosis and pulmonary heart disease (see Causes of caudate lobe hypertrophy). In severe congestive heart failure and right-sided heart failure, patchy enhancement and congestive liver changes similar to those depicted in BCS may occur; however, the hepatic veins are enlarged rather than attenuated.

ULTRASOUND

Section 7 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Findings

Color-flow Doppler (CFD) images demonstrate abnormality of the anatomy or flow, such as the following:

• Part of or the entire right hepatic vein (regardless of apparent intraluminal echoes), with no flow or inappropriately directed flow
• No depiction of part or all of a hepatic vein using either conventional US or CFD of the right side of the liver
• Discontinuity between the main hepatic vein and the IVC
• Reversed flow in hepatic veins (ie, bicolor hepatic veins)
• Intrahepatic collaterals (collateralization is suggested when reversed flow is found, which may be seen before and after shunting)
• • Intrahepatic veins that communicate with systemic vessels via subcapsular collaterals
  • Collateral vessels that shunt blood from occluded veins to nonoccluded veins or to enlarged inferior hepatic veins or caudate lobe veins
  • Large collaterals that drain directly into the IVC
• Portal vein changes
• • Flow may be hepatopetal or hepatofugal
  • Portal flow dynamics may change between examinations
• IVC changes
• • No flow 
  • Reduced flow
  • Very slow flow
  • Balanced bidirectional flow
  • Thrombus or tumor within the IVC
  • Compression of the caudate lobe
  • Long or localized segmental narrowing
  • Echogenic membrane or fibrous cord in the IVC (easily depicted by CFD), a common cause of chronic BCS

Conventional US may show gallbladder wall thickening, ascites, patchy liver echo pattern, splenomegaly, hypertrophied caudate lobe, and ascites.

Veno-occlusive disease of the liver may be regarded as a variant of BCS. Unlike classic BCS, occlusion of the IVC or major hepatic veins does not occur. The basic pathophysiology is related to occlusion of the postsinusoidal venules by an inflammatory process.

Earlier research suggested that establishing a diagnosis by using US is possible because it demonstrates an increase in the resistive index in the hepatic artery and a decrease or reversal of flow in the portal vein. However, results of later research have been disappointing, reflecting the nonspecificity of the signs mentioned above. Thus, at the present stage, veno-occlusive disease remains a clinical or histologic diagnosis.

Transjugular intrahepatic portosystemic shunts (TIPS) are placed percutaneously via the jugular vein. TIPS placement is becoming popular as a definitive procedure for decompressing the portal venous system or as prelude to liver transplantation. Doppler US is a sensitive and relatively specific means used to evaluate TIPS malfunction. Sonographic evaluation of the shunt usually is performed within 24 hours after shunt placement to establish baseline velocities within the portal vein, hepatic vein, and shunt. Follow-up studies usually are performed every 3 months unless the clinical setting dictates a more emergent examination. The main object of Doppler study of a TIPS is to document flow in the shunt and search for stenosis.

Accuracy of Doppler US in depicting shunt malfunction depends on several US parameters, which include changes in peak shunt velocity, distal shunt velocity, portal vein velocity, and the presence of antegrade flow in the left and right portal veins. Flow velocities in the portal vein may double, compared to preoperative velocities, with successful TIPS placement. Direct observation of shunt thrombosis is possible on color duplex Doppler images. Echo-enhanced color Doppler US also can be helpful in the assessment of TIPS.

Complications of TIPS detectable on US images include the following:

• Early complications
• • Intraperitoneal hemorrhage
  • Shunt thrombosis
  • Neck hematoma
  • Compromise of hepatic blood supply
  • Portal vein thrombosis
  • Hepatic artery occlusion
  • Hepatic infarction
  • Failure of stent deployment
  • Inadequate stent expansion
  • Stent retraction
  • Stent fracture
  • Biliary obstruction
• Delayed complications - shunt stenosis
• • Pseudointimal hyperplasia
  • Hepatic vein stenosis

Degree of Confidence

US is noninvasive and has high sensitivity and specificity. Sonographic images easily depict the echogenic membrane or fibrous cord in the IVC, which is a common cause of chronic BCS.

False Positives/Negatives

Sonography is not an accurate means for measuring the pressure gradient in the IVC, but because the choice of an appropriate decompressive shunt (mesoatrial vs portocaval or mesocaval) depends on the presence of a pressure gradient within the IVC, venography is likely to remain an important part of the evaluation of BCS in any patient in whom surgical decompression is considered.

Duplex US 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 suggests the presence of cirrhosis.

The differential diagnosis of hepatofugal portal venous flow includes portal hypertension, BCS, side-to-side portocaval shunts, surgical/spontaneous splenorenal shunts with cirrhosis, tricuspid regurgitation (tricuspid flow reversal), and severe congestive cardiac failure.

Passive hepatic congestion due to compromise of liver venous drainage causes passive hepatic venous congestion, which is not an uncommon complication of congestive heart failure and constrictive pericarditis, in which the elevated central venous pressure is transmitted from the right atrium to the hepatic veins. Passive hepatic congestion often is accompanied by hepatomegaly. Hepatocytes are extremely sensitive to ischemic injury, even over short periods. A variety of cardiac-related circulatory disorders may cause ischemic injury in the liver.

On sonographic images, the IVC is depicted as distended and associated with dilated hepatic veins. The normal variation of IVC caliber during respiration is lost. Ascites may occur. The portosplenic veins may show variable degrees of dilatation. Hepatomegaly occasionally may be associated with mild-to-moderate splenomegaly. Echogenicity of the liver varies from echo poor to bright. In acute venous congestion, the starry-sky appearance may occur. Pleural and/or pericardial effusions are often present. Cardiomegaly and cardiac rhythm abnormalities may be depicted on liver scans.

NUCLEAR MEDICINE

Section 8 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Findings

As a result of retained venous drainage and, hence, comparatively normal hepatic function of the caudate lobe, ^99mTc sulfur colloid uptake is increased (ie, hot) in the caudate lobe at the expense of the rest of the liver, in which uptake may be normal, reduced, absent, or patchy. Often, colloid shifts to the spleen and bone marrow. Wedge-shaped focal peripheral defects are occasionally identified.

Degree of Confidence

^99mTc sulfur colloid scanning is an elegant noninvasive technique in which findings may not only suggest the diagnosis of BCS but also provide a rough index of liver function and the presence or absence of splenomegaly.

False Positives/Negatives

Hot spots depicted on ^99mTc sulfur colloid scans may appear within healthy liver segments in patients with diffuse liver disease resulting from any cause. Superior vena caval obstruction (not associated with BCS) is a far less frequent cause of a hot spot within the liver and is produced by collateral flow through the intercostal to the paraumbilical vein, hepatic veins, and right atrium. Between the paraumbilical and hepatic veins, radionuclide uptake may occur in Kupffer cells within a localized area of the liver. Increased activity within focal nodular hyperplasia is a well-known phenomenon and exploited diagnostically. False-negative diagnoses may also occur.

ANGIOGRAPHY

Section 9 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Findings

• Hepatic and celiac-axis angiograms reveal hepatosplenomegaly; intrahepatic arteries are markedly stretched and bowed by the edematous liver.
• In patients with long-standing disease, the hepatic arteries may dilate, and arteriovenous shunting may develop.
• The hepatogram phase may be intense and prolonged and may demonstrate a mottled appearance.
• Large lakes of sinusoidal contrast accumulation are occasionally seen.
• Progression of contrast material through the liver may be slow, often with outflow through the portal vein, which has been termed the cul-de-sac phenomenon.
• Opacification of splenic and portal veins is usually faint but adequate to demonstrate portal vein patency and hepatopetal flow. Flow may become bidirectional or centrifugal in chronic disease.
• Portography may demonstrate central hepatic enhancement of the liver with normal hepatopetal flow.
• Splenoportographic findings depend on the duration of disease. In early stages when the flow within the portal vein is centripetal, the portal vein radicles may be stretched, and emptying is delayed. In later stages, portal venous flow reverses, and the splenic and portal veins may not fill.
• Generally, arteriography is not recommended in patients with BCS and usually is performed to investigate hepatosplenomegaly and/or portal hypertension in patients in whom the diagnosis of BCS is not suspected.
• Major vascular findings in patients with BCS occur on inferior venacavography and hepatic venography.
• • The IVC may demonstrate occlusion by a thrombus or tumor at the renal or hepatic level. This appearance usually is adequate for a diagnosis.
  • If the IVC is occluded, the hepatic veins may be catheterized via the jugular/axillary veins through the right atrium.
  • Inferior venacavogram shows a variety of changes.
  • • In the acute form, liver swelling usually gives rise to constriction of the intrahepatic IVC.
    • On the anteroposterior view, the IVC may appear as a contrast-filled, thin, dense, stringlike structure reaching the diaphragm.
    • IVC obstruction by a web may be observed.
    • IVC obstruction from a tumor or thrombus may be seen.
  • A hepatic venogram obtained with selective catheterization of a hepatic vein may show a variety of changes.
  • • A fine-mesh spiderweb appearance may be depicted of the many collateral channels that develop between hepatic venules and systemic veins.
    • A coarse-mesh spiderweb pattern may be depicted, in which changes as above are seen but an intrahepatic network of collaterals cover larger spaces of 1-2 cm in diameter.
    • Hepatic vein stenosis usually occurs near the orifice of the major hepatic veins; collaterals can be seen coursing around the stenosis.
    • Veno-occlusive disease (Senecio) pattern may be seen, in which contrast injection produces a pattern similar to that found in the coarse-mesh spiderweb pattern; however, the major hepatic veins are patent. The use of contrast enhancement shows a patent but narrowed hepatic vein.
    • Hepatic vein occlusion may be caused by tumor, which is most commonly associated with hepatocellular carcinoma.

If the roots to the hepatic veins are occluded, direct-puncture hepatogram may be performed, in which the liver is accessed directly by needle puncture and contrast is injected into the liver parenchyma. The contrast material usually breaks through into the proximal hepatic venules, subsequently filling the collateral channels and resulting in the spiderweb pattern.

Degree of Confidence

Both arteriographic and splenoportographic findings may demonstrate the cause of hepatic venous occlusion. Inferior venacavography and hepatic venography findings may be specific for BCS. The greatest benefit of these procedures is accrued with the diagnosis of a web across the hepatic vein or IVC because, at the moment, no other modality can help in diagnosing this disorder with confidence.

The examination is safe. A transient elevation of serum enzyme levels has been reported after wedged hepatic venography, but the evaluation appears to be of no consequence. Sonography is making inroads in the diagnosis of BCS, but venography is likely to remain an important part of the evaluation of BCS in any patient in whom surgical decompression is considered.

False Positives/Negatives

The arterial pattern in BCS is similar to that in alcohol-induced hepatitis. The cul-de-sac phenomenon also may be seen in patients with heart failure; however, this can be excluded on clinical grounds. Marked narrowing of the IVC may occur in patients with cirrhosis; however, unlike the predominantly side-to-side compression found in BCS, the narrowing is usually circumferential. Unilobar BCS is a rare occurrence, in which hepatic venous occlusion is asymmetric and incomplete. Occlusion gives rise to intrahepatic flow competition, and portoportal and hepatic vein–portal shunts give rise to unusual contrast parenchymal patterns, leading to difficulties in diagnosis.

INTERVENTION

Section 10 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Biopsy analysis of a specimen from the liver may be required in some patients for histologic confirmation. Optimum treatment or palliation of BCS depends on the cause. IVC webs can be treated with transcardiac membranectomy or percutaneous stent placement following balloon dilatation. Some patients with IVC obstruction, but with sparing of the hepatic veins, may be suitable for IVC shunting directly into the right atrium. If the hepatic veins are occluded, a portosystemic shunt may be fashioned, such as a mesocaval shunt. If the IVC and hepatic veins are both occluded, patients may benefit from a mesoatrial shunt. Many patients with tumors such as renal cell carcinoma and hepatocellular carcinoma, in whom curative surgery is unsuitable, may benefit from palliative juguloperitoneal shunting of intractable ascites.

The TIPS procedure may benefit selected patients. Liver transplantation may be considered for advanced cases. Although most of the procedures are surgical rather than radiologic, they do require accurate radiologic assessment of the IVC, liver, portal vein, and hepatic veins prior to intervention.

Medical/Legal Pitfalls

• BCS is an uncommon cause of portal hypertension. The diagnosis is difficult to establish clinically, and many cases are discovered at autopsy. Patients usually do not have alcoholism.
• A hypercoagulation state, renal cell carcinoma, or hepatocellular carcinoma presenting with hepatomegaly, ascites, and often abdominal pain should always raise the possibility of BCS. A diagnosis should be sought actively, because palliation can be offered to most patients.
• Recognition of an IVC web, which presumably is a congenital cause of BCS, is of utmost importance. This is the only curable form of the disease. Cure is attained by transcardiac membranectomy or percutaneous stent placement.
• Veno-occlusive disease is a complication in as many as 25% of patients treated with bone marrow transplantation and usually occurs in the first 3 weeks after the procedure. An early diagnosis is desirable, since veno-occlusive disease has a mortality rate of 83% and patients may respond to treatment.

MULTIMEDIA

Section 11 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT SCAN
• MRI
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Multimedia
• References

Media file 1:  Diagram of hepatic venous drainage depicts the small veins that drain from the caudate lobe and adjacent part of the right lobe directly into the inferior vena cava. The veins tend to be spared in hepatic venous occlusion in patients with Budd-Chiari syndrome, giving rise to hypertrophy of the caudate lobe and adjacent part of the right lobe.
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Media file 2:  Inferior venacavogram shows compression and lateral displacement of the inferior vena cava by an enlarged caudate lobe.
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Media file 3:  Wedged hepatic venogram shows a coarse-mesh spiderweb pattern resulting from an intrahepatic network of collateral vessels.
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Media file 4:  Inferior venacavogram shows an upper inferior vena cava stenosis with reflux of the contrast into the hepatic venous circulation due to partial obstruction of the distal inferior vena cava.
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Media file 5:  Following placement of a wall stent in the upper inferior vena cava, a wide patency of the inferior vena cava is seen (same patient as in Image 6). Note the lack of reflux of contrast into the hepatic veins.
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Media file 6:  A 53-year-old man presented with nonspecific symptoms and a mild swelling of the legs. He had no features of heart failure. Abdominal B-mode sonogram shows a distended inferior vena cava with intraluminal filling defects suggestive of a thrombus within the inferior vena cava. On a thorough search, no hepatic veins were identified, but the liver presented a heterogeneous echo pattern, although no discrete mass was identified.
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Media file 7:  Technetium-99m sulfur colloid scan in a 53-year-old man who presented with nonspecific symptoms and a mild swelling of the legs. The patient had no features of heart failure (same patient as in Images 8-9). Scan shows patchy radionuclide uptake in most of the liver but intense activity in the region of the caudate lobe. Analysis of a sample from percutaneous liver biopsy revealed histologic features of Budd-Chiari syndrome.
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Media file 8:  A 42-year-old man presented with an intractable ascites of unknown cause before CT scanning and gray-scale ultrasonography were available. The patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. At one stage, the symptoms were urological, and an intravenous urogram was performed, which shows right hydronephrosis and displacement of the right lower ureter and bladder to the right. Note the unusual linear calcification in the right upper quadrant. Many years after the initial symptoms appeared, imaging techniques had advanced (see Images 12-19).
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Media file 9:  A 42-year-old man presented with an intractable ascites of unknown cause many years ago. At the time, the patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. When imaging techniques evolved, sagittal ultrasound was performed in the patient's liver and shows 2 hepatic veins, which appeared pruned, with no ramifications (same patient as in Images 11-19).
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Media file 10:  A 42-year-old man presented with an intractable ascites of unknown cause many years ago. At the time, the patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. When imaging techniques evolved, a contrast-enhanced CT scan of the upper abdomen was performed and shows extensive liver/splenic capsular and peritoneal calcification and patchy attenuation within the liver. The left lobe/caudate lobe appears hypertrophied (same patient as in Images 11-19).
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Media file 11:  A 42-year-old man presented with an intractable ascites of unknown cause many years ago. At the time, the patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. When imaging techniques evolved, unenhanced CT scan was performed and shows splenomegaly and a small ascites medial to the spleen (arrow) (same patient as in Images 12-19).
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Media file 12:  A 42-year-old man presented with an intractable ascites of unknown cause many years ago. At the time, the patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. When imaging techniques evolved, unenhanced CT scan of the pelvis was performed and shows a loculated ascites, which was responsible for the displaced bladder and right ureter as seen in Image 11 (same patient as in Images 11, 13-19).
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Media file 13:  A 42-year-old man presented with an intractable ascites of unknown cause many years ago. At the time, the patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. When imaging techniques evolved, T1-weighted axial MRI was performed through the liver and shows a low signal within the right liver (same patient as in Images 11-12, 14-19). The left lobe/caudate lobe is hypertrophied. Note the misshapen inferior vena cava.
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Media file 14:  A 42-year-old man presented with an intractable ascites of unknown cause many years ago. At the time, the patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. When imaging techniques evolved, T2-weighted axial MRI was performed through the liver and shows a high signal within the right liver (same patient as in Images 11-13, 15-19). The left lobe/caudate lobe is hypertrophied. Note the misshapen inferior vena cava.
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Media file 15:  A 42-year-old man presented with an intractable ascites of unknown cause many years ago. At the time, the patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. When imaging techniques evolved, axial short-tau inversion recovery MRI was performed through the liver and shows a high signal (edema) within the right liver (same patient as in Images 11-14, 16-19). The left lobe/caudate lobe is hypertrophied. Note the misshapen inferior vena cava.
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Media file 16:  A 42-year-old man presented with an intractable ascites of unknown cause many years ago. At the time, the patient had repeated juguloperitoneal shunt placements for relief of the ascites. The ascites diminished, but the patient experienced persistent vague abdominal symptoms. When imaging techniques evolved, a wedged hepatic venogram was performed and shows a fine-mesh spiderweb pattern resulting from an intrahepatic network of collateral vessels (same patient as in Images 11-15, 17-18). At this stage, direct questioning elicited that the patient had been accidentally exposed to radiation in the late 1950s. Analysis of a biopsy specimen confirmed Budd-Chiari syndrome. The cause of the capsular/peritoneal calcification could not be determined, but 2 factors may have been the cause: radiation damage or the repeated placement of jugular peritoneal shunts.
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Media file 17:  Budd-Chiari syndrome: Two ultrasound images from a 13-year old boy who presented with jaundice, abdominal distention, and features of hepatic encephalopathy and sepsis. Ultrasound showed bilateral pleural effusions, ascites, and no flow within the hepatic veins but a patent IVC.
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Media file 18:  Budd-Chiari syndrome: Two ultrasound images from a 13-year old boy that presented with jaundice, abdominal distention, and features of hepatic encephalopathy and sepsis. Ultrasound showed bilateral pleural effusions, ascites, and no flow within the hepatic veins but a patent IVC.
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Media file 19:  Budd-Chiari syndrome: Six ultrasound images of a 28-year-old female who presented with a nonspecific illness and abnormal liver function tests. The ultrasound scans show no flow in hepatic veins, compressed IVC, enlarged caudate lobe, splenomegaly, and varices at the splenic hilum.
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Media file 20:  Budd-Chiari syndrome: Six ultrasound images of a 28-year-old female who presented with a nonspecific illness and abnormal liver function tests. The ultrasound scans show no flow in hepatic veins, compressed IVC, enlarged caudate lobe, splenomegaly, and varices at the splenic hilum.
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Media file 21:  Budd-Chiari syndrome: Six ultrasound images of a 28-year-old female that presented who a nonspecific illness and abnormal liver function tests. The ultrasound scans show no flow in hepatic veins, compressed IVC, enlarged caudate lobe, splenomegaly, and varices at the splenic hilum.
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Media file 22:  Budd-Chiari syndrome: Six ultrasound images of a 28-year-old female who presented with a nonspecific illness and abnormal liver function tests. The ultrasound scans show no flow in hepatic veins, compressed IVC, enlarged caudate lobe, splenomegaly, and varices at the splenic hilum.
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Media file 23:  Budd Chiari Syndrome: Six Ultrasound images on a 28-year old female that presented with a non-specific illness and abnormal liver function tests. The Ultrasound scans show no flow in hepatic veins, compressed IVC, enlarged caudate lobe, splenomegaly and varices at the splenic hilum.
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Media file 24:  Budd-Chiari syndrome: Six ultrasound images of a 28-year-old female who presented with a nonspecific illness and abnormal liver function tests. The ultrasound scans show no flow in hepatic veins, compressed IVC, enlarged caudate lobe, splenomegaly, and varices at the splenic hilum.
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Media file 25:  Budd-Chiari syndrome: Contrast-enhanced axial CT scan showing a large ascites, patchy enhancement of the liver, an enlarged caudate lobe, attenuated hepatic veins, hepatic vein–portal vein shunts, and a thrombus within the intrahepatic IVC.
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Media file 26:  Budd-Chiari syndrome: Contrast-enhanced axial CT scan showing a large ascites, patchy enhancement of the liver, an enlarged caudate lobe, attenuated hepatic veins, hepatic vein–portal vein shunts, and a thrombus within the intrahepatic IVC.
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Media file 27:  Budd-Chiari syndrome: Contrast-enhanced axial CT scan showing a large ascites, patchy enhancement of the liver, an enlarged caudate lobe, attenuated hepatic veins, hepatic vein–portal vein shunts, and a thrombus within the intrahepatic IVC.
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Media file 28:  Acute Budd-Chiari syndrome with recovery. A 36-year-old female patient with known Behcet's disease presented with abdominal distention, leg edema, and abnormal liver function tests. Nonenhanced in-phase T2WI shows heterogeneity of the liver parenchyma. Note the thrombus in the IVC and the ascites.
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Media file 29:  Acute Budd-Chiari syndrome with recovery. A 36-year-old female patient with known Behcet's disease presented with abdominal distention, leg edema, and abnormal liver function tests. Nonenhanced in-phase T2WI shows heterogeneity of the liver parenchyma. Note the thrombus in the IVC and the ascites.
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Media file 30:  Acute Budd-Chiari syndrome with recovery. A 36-year-old female patient with known Behcet's disease presented with abdominal distention, leg edema, and abnormal liver function tests. Nonenhanced in-phase T2WI shows heterogeneity of the liver parenchyma. Note the thrombus in the IVC and the ascites.
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Media file 31:  Acute Budd-Chiari syndrome with recovery. A 36-year-old female patient with known Behcet's disease presented with abdominal distention, leg edema, and abnormal liver function tests. Nonenhanced in-phase T2WI shows heterogeneity of the liver parenchyma. Note the thrombus in the IVC and the ascites.
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Media type:  Image