Budd-Chiari syndrome: detection with color Doppler sonography.

The value of color Doppler sonography in evaluating newly diagnosed Budd-Chiari syndrome in five patients was studied. Hepatic venous findings included absence of vessels (one patient), flow reversal (two patients), narrowing (four patients), and tortuosity (three patients). Detected collaterals included hepatic venous to hepatic venous (four patients), hepatic venous to subcapsular systemic venous (two patients), and portosystemic (three patients). Hepatic venous spectral Doppler waveforms were flat and essentially aphasic in four patients, indicative of distal hepatic venous compression. The inferior vena cava was markedly compressed in two patients and slightly compressed in one. Color Doppler sonography allowed more reliable and confident identification of irregular, compressed, or otherwise abnormal hepatic veins than did conventional sonography. Color Doppler sonography also showed collateral vessels that were undetected with conventional sonography or other imaging techniques. Our results suggest that color Doppler sonography may be a valuable tool in the initial diagnosis and evaluation of suspected Budd-Chiari syndrome.     

Hepatic arterial color doppler signals in Caroli's disease

Three siblings with congenital dilatation of the intrahepatic bile ducts (Caroli's disease) are presented. Bile duct pathology was associated with congenital hepatic fibrosis and polycystic renal disease in all three patients. On color Doppler imaging (CD imaging), multiple small color Doppler signals were observed in the vascular radicles within the dilated bile ducts or in the center of the lumen apart from the vascular radicles, as well as in other well-known sonographic findings such as bile duct dilatations and bilary calculi. Doppler frequency spectral analysis confirmed all these color signals as arterial in origin in all patients, revealing pulsatile wave patterns. In spite of the fact that portal venous radicles have been well described on conventional sonograms or computed tomography (CT), continuous wave patterns of venous flow on spectral analysis were not detected in all patients. Identification of such less emphasized arterial flow may add another clue in the diagnosis and pathogenesis of this rare disease entity. In conclusion, color Doppler signals of arterial wave pattern within the dilated bile ducts are another helpful diagnostic criteria in previously reported sonographic findings, and these color signals are easily depicted on sonograms with color mapping.     

Budd-Chiari syndrome: value of duplex sonography and colour Doppler imaging for diagnosis and follow-up

This retrospective study was designed to evaluate duplex sonography in the diagnosis and follow-up of patients with Budd-Chiari syndrome. Thirteen patients with clotting disease and histologically proven Budd-Chiari syndrome (3 acute and 10 chronic cases) were examined, using conventional duplex sonography (n=5) or colour-coded duplex sonography (n=8). Results were compared with CT in 6 cases, MRI in 11, coeliac and mesentric angiography in 5, and hepatic wedge venography and cavography in 6. Of 39 hepatic veins examined, 33 had an abnormal appearance on ultrasound studies: endoluminal thrombus, stenosis, dilatation, thick wall echoes. Doppler findings included total obstruction of 8 hepatic veins, reversed flow in 22 hepatic veins and intrahepatic collaterals with continous non-phasic flow in all cases. Duplex sonography showed portal thrombosis (n=1), evidence of portal hypertension (n=8) and inferior vena cava thrombosis (n=2). Nine patients were treated surgically. Patency of portocaval shunts was correctly assessed with colour coded duplex sonography in 8 of 9 patients. We believe that colour Doppler imaging is the procedure of choice for initial diagnosis of Budd-Chiari syndrome. Correspondence to: M. F. Bellin     

Diagnosis of portal vein thrombosis: value of color Doppler imaging.

This study was undertaken to determine the accuracy of color Doppler imaging in the diagnosis of portal vein thrombosis. Two hundred fifteen patients were studied with color Doppler imaging to determine patency of the main portal vein. Sonographic findings were confirmed in 75 patients, aged 19 to 66 years. Correlation with angiography was obtained in 13 patients, and surgical correlation was obtained in the remaining 62. Nine patients had portal vein thrombosis on the basis of these gold standards. Sonograms were classified as showing either patency or thrombosis, depending on the ability to show color flow within the main portal vein. Agreement between sonography and angiography or surgery was found in 69 patients (61 patent, eight thrombosed). One patient with a patent portal vein at sonography was found to have a thrombosed vessel at surgery, whereas five patients without portal venous flow at sonography had patent vessels at angiography (one patient) or surgery (four patients). Overall sensitivity and specificity for detection of portal vein thrombosis were 89% and 92%, with an accuracy of 92%, a false-negative rate of 0.11, a negative predictive value of 0.98, and a positive predictive value of 0.62. We postulate that the majority of errors in our study occurred in vessels that, although patent, had only sluggish flow, which could not be resolved because of technical limitations. We conclude that color Doppler imaging is a valuable screening procedure for the assessment of portal vein patency. If the sonogram shows a patent portal vein, no further studies are required. However, a lack of demonstrable flow does not always indicate thrombosis, and other imaging studies should be performed for confirmation.     

Contrast-enhanced versus conventional and color Doppler sonography for the detection of thrombosis of the portal and hepatic venous systems

OBJECTIVE: We conducted a prospective study to compare sonography, color Doppler sonography, and contrast-enhanced sonography for the detection and characterization of portal and hepatic vein thrombosis complicating hepatic malignancies. SUBJECTS AND METHODS: Three hundred sixteen patients with biopsy-proved hepatic tumors were studied at baseline and 3 months later with sonography, color Doppler sonography, and contrast-enhanced sonography. Thrombosis was defined as the presence of intraluminal echogenic material at sonography, absence of intraluminal color signals at color Doppler sonography, and presence of nonenhancing intraluminal area at contrast-enhanced sonography. Thrombi were considered malignant if they displayed continuity with tumor tissue at sonography, intrathrombus color signals at color Doppler sonography, and enhancing signals at contrast-enhanced sonography, both having arterial waveforms at Doppler spectral examination. Definitive diagnoses were obtained by sonographically guided biopsy except for thrombi displaying at conventional sonography unequivocal continuity with tumor tissue. RESULTS: Thrombosis was detected in 79 (25.0%) of 316 patients at baseline and in 83 (26.3%) of 316 patients after 3 months. Eighty-one (97.6%) of the 83 thrombi were malignant. Definitive diagnosis was performed by imaging in 60 (72.3%) of the 83 cases and by biopsy in 23 cases (27.7%). For thrombus detection, contrast-enhanced sonography displayed significantly higher sensitivity than color Doppler sonography (p = 0.004) and borderline superiority over sonography (p = 0.058). For thrombus characterization, contrast-enhanced sonography was significantly more sensitive than color Doppler sonography (p < 0.0005) and conventional sonography (p = 0.02). CONCLUSION: Contrast-enhanced sonography is superior to sonography and color Doppler sonography for the detection and characterization of portal and hepatic vein thrombosis complicating hepatic malignancies.     

Duplex sonography of the splenoportal axis

48 patients with partial or complete portal vein thrombosis or tumor stenosis were examined by pulsed Doppler duplex scanning. In addition to the analysis of morphological changes, the pulsed Doppler duplex system yields functional data on the acceleration of blood flow in stenosis, flow in partial thrombosis and in differentiation between tubular cystic structures like arterial vessels, venous collaterals and dilated bile ducts. Qualitative and quantitative measurements of portal blood flow were performed in 55 cirrhotics and 15 healthy volunteers. Portal venous velocity and portal venous blood flow were significantly reduced in patients with cirrhosis. In 46 cases a hepatopetal blood flow was shown. In five cases a hepatofugal flow and in four cases a stagnant flow was found in the portal vein. Spontaneous portal systemic collaterals with hepatofugal flow were shown in 41% of cases. 11 patients with surgical portacaval shunts were examined. Patency was demonstrated in five patients where the anastomotic site was visible. Pulsed Doppler duplex sonography proved a valuable tool in the assessment of morphologic changes and revealed qualitative and quantitative data of portal venous hemodynamics.     

Doppler sonographic abnormalities suggestive of venous congestion in the right lobe graft of living donor liver transplant recipients

OBJECTIVE: Establishing optimal hepatic venous outflow is the key for a successful outcome of living donor liver transplantation using a right lobe graft. The purpose of this article is to illustrate the surgical techniques of middle hepatic vein reconstruction with an interposition vein graft in living donor liver transplant recipients using a modified right lobe graft, normal postoperative Doppler sonographic findings, and various Doppler sonographic abnormalities suggestive of hepatic venous congestion. CONCLUSION: Hepatic venous congestion after living donor liver transplantation using a right lobe graft may produce various abnormalities on Doppler sonography. In addition to allowing the patency of the middle hepatic vein tributaries and interposition vein graft to be assessed during the early postoperative period, Doppler sonography can depict the flow direction in the portal vein and in the middle hepatic vein tributaries; therefore, Doppler sonography can reveal reversal of portal flow direction in patients with acute and severe venous congestion and can show the presence of a functional intrahepatic anastomosis between the hepatic vein tributaries during the follow-up period in those with improved congestion.     

Doppler sonography of the native liver

Doppler sonography is being used routinely in evaluating the vascular structures of the native liver because of its ease of use, lower cost, easier availability, lack of need for X-ray and accuracy. Doppler sonography can well demonstrate the vascularization of liver tumors, portal vein thrombosis, portal vein abnormalities in patients with portal hypertension and hepatic venous findings in patients with Budd Chiari syndrome. The purpose of this article is to present information about Doppler sonography of the native liver and to show its usefulness in the evaluation of hepatic vascular diseases.     

Sonography and MR imaging of posterior tibial tendinopathy.

OBJECTIVE: The purpose of the study is to describe the appearance of the posterior tibialis tendon on MR imaging and high-resolution sonography with color and power Doppler imaging and to determine whether sonography is as accurate for diagnosing tendinosis as MR imaging. SUBJECTS AND METHODS: Fifteen healthy volunteers and 31 patients (44 tendons) who were clinically suspected of having posterior tibial tendinopathy were prospectively evaluated with MR imaging and sonography. RESULTS: On MR imaging, the normal tendon was elliptic on cross section and showed low signal intensity on all sequences. Minimal peritendinous enhancement and fluid were seen. On sonography, the tendon showed homogeneous longitudinal echogenic fibers. No flow was seen in or around the tendon. Tendinopathy was characterized by enhancement of the tendon on MR imaging (19/44 tendons); intratendinous flow on color Doppler sonography (16/44 tendons); increase in the anteroposterior diameter causing a rounding of the tendon (18/44 tendons); and inhomogeneity of the tendon (16/44 tendons on MR imaging and 21/44 tendons on sonography). Peritendinosis was characterized by peritendinous enhancement on MR imaging (29/44 tendons); flow on color Doppler sonography (20/44 tendons); and increased soft tissue (20/44 tendons on MR imaging and 27/44 tendons on sonography). When compared with MR imaging, the sensitivity and specificity of sonography for diagnosing tendinopathy were 80% and 90%, respectively, and for diagnosing peritendinosis were 90% and 80%. Addition of abnormal size to the structural abnormality criteria did not improve diagnostic ability. CONCLUSION: Sonography can be useful as the initial imaging study in evaluating abnormalities caused by posterior tibial tendinopathy.     

Venoocclusive liver disease after bone marrow transplantation: findings at duplex sonography.

Ascites, thickening of the gallbladder wall, and reversal of portal flow are documented sonographic findings in venoocclusive disease of the liver. The frequency and specificity of these findings and their relationship to the severity of this disease have not been studied. In an attempt to clarify these issues, 65 patients who had bone marrow transplantations were prospectively studied with serial B-scans and duplex color Doppler sonography. For all patients, assessment included liver size and texture, thickening of the gallbladder wall (greater than 10 mm), and presence of ascites. Doppler flow velocity profiles were obtained from the portal vein, hepatic veins, and inferior vena cava. The hepatic artery resistive index (RI) was calculated. Twenty volunteers were also studied to establish normal flow values. Nineteen patients had documented venoocclusive disease, nine had hepatic graft-vs-host disease (GVHD) (five after proved venoocclusive disease), two had hepatitis, and 40 had no clinical or biochemical evidence of liver injury after bone marrow transplantation. Ascites (n = 16), thickening of the gallbladder wall (n = 8), hepatomegaly (n = 8), and altered liver texture (n = 3) were not distinguishing features of venoocclusive disease. Mean hepatic artery RI was as follows (ranges are in parentheses): control group, 0.69 (0.58-0.76); venoocclusive disease patients, 0.81 (0.75-0.87); GVHD patients, 0.69 (0.63-0.71); all other patients after bone marrow transplantation, 0.66 (0.61-0.71). The RI values in venoocclusive disease were significantly elevated, but an incremental rise in RI with increasing severity of the disease was not seen. Abnormalities in portal vein flow were seen in only two patients: in one with fatal venoocclusive disease, reversed portal flow developed, and in one with GVHD, portal vein thrombosis developed. Contrary to previous reports, no correlation between abnormalities in portal flow and venoocclusive disease was seen. Flow velocities in the hepatic veins and the inferior vena cava were not significantly different from values in the volunteer group. These results suggest that a significant elevation of the hepatic artery RI may be a sensitive index of liver damage related to venoocclusive disease after bone marrow transplantation and an important distinguishing sonographic feature.     

Portal venous system: evaluation with contrast-enhanced 3D MR portography

The purpose of this study is to compare contrast-enhanced three-dimensional (3D) magnetic resonance (MR) portograms to Doppler sonography in detection of portal venous abnormalities. Thirty-five consecutive patients, who were suspected of having portal venous system abnormalities, were examined with MR portography and Doppler sonography. Vascular abnormalities were identified in 27 of 35 patients. There was statistically significant agreement between the results of MR portography and Doppler sonography. The major limitation of contrast-enhanced 3D MR portography was its inability to provide objective hemodynamic data regarding flow direction and flow pattern.     

Perfusion imaging of the liver: current challenges and future goals

Improved therapeutic options for hepatocellular carcinoma and metastatic disease place greater demands on diagnostic and surveillance tests for liver disease. Existing diagnostic imaging techniques provide limited evaluation of tissue characteristics beyond morphology; perfusion imaging of the liver has potential to improve this shortcoming. The ability to resolve hepatic arterial and portal venous components of blood flow on a global and regional basis constitutes the primary goal of liver perfusion imaging. Earlier detection of primary and metastatic hepatic malignancies and cirrhosis may be possible on the basis of relative increases in hepatic arterial blood flow associated with these diseases. To date, liver flow scintigraphy and flow quantification at Doppler ultrasonography have focused on characterization of global abnormalities. Computed tomography (CT) and magnetic resonance (MR) imaging can provide regional and global parameters, a critical goal for tumor surveillance. Several challenges remain: reduced radiation doses associated with CT perfusion imaging, improved spatial and temporal resolution at MR imaging, accurate quantification of tissue contrast material at MR imaging, and validation of parameters obtained from fitting enhancement curves to biokinetic models, applicable to all perfusion methods. Continued progress in this new field of liver imaging may have profound implications for large patient groups at risk for liver disease.     

Duplex sonography of hepatic artery thrombosis after liver transplantation

When hepatic artery thrombosis occurs after liver transplantation, another transplantation is required to ensure the patient's survival. Because of the importance of establishing this diagnosis, we reviewed the results of duplex sonography in 37 angiographically or surgically proved cases of hepatic artery thrombosis after liver transplantation. There were 20 children and 17 adults. Ten of the 20 children had angiographically documented hepatopetal arterial collaterals. Such collaterals were not seen in the adult patients. This subset of patients was evaluated separately to determine if intrahepatic arterial blood flow reestablished by collaterals after hepatic artery thrombosis was a cause of false-negative Doppler studies. Thirty-four (92%) of the 37 cases of hepatic artery thrombosis were correctly identified by Doppler. A Doppler pulse was not identified in any of the children with arterial collaterals. We conclude that duplex sonography is sensitive in detecting hepatic artery thrombosis after liver transplantation. Furthermore, the presence of blood flow in hepatopetal arterial collaterals does not cause false-negative examinations.     

Hemodynamic changes in portal circulation after portosystemic shunts: use of duplex sonography in 43 patients

Forty-five patients with 46 surgical portosystemic shunts were examined by duplex Doppler sonography, and the results were compared with those of esophageal endoscopy, angiography, surgery, and clinical follow-up. Thirty-eight shunts were patent, and in 33 of these, the shunt was directly visualized and flow was observed with Doppler sonography. Eight shunts were obstructed. After a successful portosystemic shunt procedure, flow in the shunted splanchnic vein was directed toward the shunt and the systemic vein. We studied the intrahepatic portal venous circulation in all of the patients; we found that in the presence of patent portosystemic shunt, portal flow is hepatofugal. This reversal of blood flow occurred in all but four patients. In the end-to-side portacaval shunt, where the portal vein is ligated, blood in intrahepatic portal branches presumably reaches the shunt through perihepatic collaterals. In the presence of a thrombosed shunt, intrahepatic portal venous flow was hepatopetal. To our knowledge, this is the first noninvasive in vivo study of intrahepatic portal circulation after portosystemic shunt surgery. The duplex Doppler evaluation of portosystemic shunts appears to be reliable and should be the method of choice for shunt patency assessment in patients with recurrent signs of portal hypertension. In addition to demonstrating flow at the site of the anastomosis, the Doppler study may yield an easy and reliable sign of shunt patency: reversed flow (hepatofugal flow) in the intrahepatic portal veins probably signals a patent shunt, even if the site of the anastomosis cannot be visualized directly by sonography.     

Color Doppler sonography of hepatocellular carcinoma before and after treatment by transcatheter arterial embolization.

Color Doppler sonographic findings on 38 lesions in 31 patients who had primary hepatocellular carcinoma were evaluated before and after transcatheter arterial embolization and compared with dynamic CT and hepatic arteriographic findings. All lesions that were observed with dynamic CT or arteriography were correctly identified on color Doppler sonography. Peritumoral pulsatile flow was the predominant color Doppler flow seen in all lesions. Mixed pulsatile and continuous flow were noted in larger tumors and in tumors with a higher degree of vascularity, as determined by arteriography. Two weeks after treatment, color Doppler flow was still identified in 18 lesions (47%), corresponding to dynamic CT or arteriographic findings documenting residual tumor. Histopathologic examination, performed in 10 other lesions, showed that the tumor was completely necrotic in five. These five necrotic tumors were not visible on color Doppler flow images after treatment. Viable tumor was observed in the five remaining lesions, all of which were shown on color Doppler flow images after treatment. During the 6- to 16-month follow-up period, color Doppler flow images showed recurrence of 13 (50%) of 26 lesions, corresponding to tumor recurrence as shown by CT and arteriography. We conclude that color Doppler sonography is useful for imaging hepatocellular carcinoma, for evaluating residual tumor after treatment, and for imaging tumor recurrence during follow-up.     

Hepatofugal flow in the portal venous system: pathophysiology, imaging findings, and diagnostic pitfalls.

Hepatofugal flow (ie, flow directed away from the liver) is abnormal in any segment of the portal venous system and is more common than previously believed. Hepatofugal flow can be demonstrated at angiography, Doppler ultrasonography (US), magnetic resonance imaging, and computed tomography (CT). The current understanding of hepatofugal flow recognizes the role of the hepatic artery and the complementary phenomena of arterioportal and portosystemic venovenous shunting. Detection of hepatofugal flow is clinically important for diagnosis of portal hypertension, for determination of portosystemic shunt patency and overall prognosis in patients with cirrhosis, as a potential pitfall at invasive arteriography performed to evaluate the patency of the portal vein, and as a contraindication to specialized imaging procedures (ie, transarterial hepatic chemoembolization and CT during arterial portography). Hepatofugal flow is generally diagnosed at Doppler US without much difficulty, but radiologists should beware of pitfalls that can impede correct determination of flow direction in the portal venous system.     

MR imaging of portal vein thrombosis

MR imaging is emerging as a potential means of detecting portal venous thrombosis (PVT). Therefore, we attempted to establish specific criteria with which to diagnose PVT on conventional spin-echo images. In a retrospective review of 342 consecutive abdominal MR scans performed with a 0.5-T magnet, we identified nine patients with persistent signal in the portal vein and used the findings in these patients to establish criteria with which to diagnose PVT. We subsequently applied these criteria to 109 additional consecutive abdominal MR scans performed with the same magnet. Fifteen cases were found in which all images showed either (1) signal involving the entire width of the portal vein lumen, which approximated (with T1 weighting) and exceeded (with T2 weighting) the intensity of the hepatic parenchyma in images in which the hepatic veins showed a complete flow void or (2) complete nonvisualization of the portal vein and its major branches in images that showed a flow void in portal venous collaterals and hepatic veins. All patients had unequivocal findings of PVT on at least one other imaging study (CT or sonography) or at surgery. Although the sensitivity of these signs could not be calculated, their specificity was 100%. We conclude that in the presence of these signs, the diagnosis of PVT can be made with confidence.     

Color flow Doppler characterization of focal hepatic lesions.

OBJECTIVE. The purpose of this study was to determine the sensitivity and specificity of color flow Doppler sonography for the specific diagnosis of focal hepatic lesions. SUBJECTS AND METHODS. Color flow Doppler images of 118 focal hepatic lesions in 108 patients were analyzed prospectively. In most patients, liver disease was suspected or known to be present before the Doppler images were obtained. Experienced sonologists obtained and interpreted all sonograms. The lesions were classified, according to their color flow pattern, into two main categories: lesions with internal vascularity and lesions with no internal vascularity. The color flow Doppler pattern of each lesion was correlated with the diagnosis of the lesion on a lesion-by-lesion basis. One hundred two lesions were proved by biopsy and 16 lesions were confirmed by evaluation with other imaging techniques. Lesions included 29 hepatocellular carcinomas, 64 metastases, one cholangiocarcinoma, and 24 benign lesions. The sensitivity and specificity of vascularity as shown by color Doppler imaging in the diagnosis of hepatocellular carcinoma were determined. RESULTS. The majority of hepatocellular carcinoma lesions (76%) had internal vascularity. Most of the metastases (67%) and benign lesions (75%) had no internal vascularity. When the presence of internal vascularity was used as the discriminating criterion, the sensitivity of color flow Doppler findings for the diagnosis of hepatocellular carcinoma was 0.76. The specificity of internal vascularity for the diagnosis of hepatocellular carcinoma vs other focal lesions was 0.69; for hepatocellular carcinoma vs metastases it was 0.67. CONCLUSION. Although most hepatocellular carcinomas have internal vascularity on color flow Doppler images, a significant number of metastases also have internal vascularity. This overlap limits the usefulness of color flow Doppler imaging for distinguishing hepatocellular carcinoma from metastatic tumors.     

MR angiography and dynamic flow evaluation of the portal venous system

We studied the value of MR angiographic techniques in imaging the portal venous system. Projection angiograms were created by postprocessing a series of two-dimensional, flow-compensated gradient-echo images. Flow velocity was determined by a bolus-tracking method with radiofrequency tagging and multiple data readout periods. Each image was acquired during a breath-hold. MR angiography was applied to six normal subjects and four patients with abnormal hemodynamics in the portal venous system. Flow velocity determined by MR was correlated with the results of duplex sonography. The main portal vein and intrahepatic branches were shown in all cases. Portosystemic collaterals were identified in all patients with portal hypertension. In normal subjects, peak flow velocities (17.9 +/- 2.8 cm/sec) on MR correlated well with values determined by duplex sonography (17.5 +/- 2.2 cm/sec) (r = .846, p less than .04). Reversed portal blood flow was shown in two patients. One patient with portal vein thrombosis had no evidence of flow by MR angiography. Our results indicate that MR angiography can provide a three-dimensional display of normal and abnormal vascular anatomy as well as functional information in the portal venous system.     

Identification of a patent paraumbilical vein by using Doppler sonography: importance in the diagnosis of portal hypertension

The aim of this study was to determine if the addition of pulsed Doppler imaging to conventional sonography allows discrimination between true paraumbilical veins of portal hypertension and the apparent vein sometimes seen in the ligamentum teres in normal subjects. Conventional sonography and Doppler sonography of the ligamentum teres were performed in 33 normal subjects and in 39 patients with portal hypertension due to chronic liver disease. An apparent ligamentum teres vessel (i.e., hypoechoic channel) was identified on sonograms in 32 (97%) normal subjects (diameter 0.6-1.9 mm) and in 35 (90%) patients with portal hypertension (diameter 1.1-22 mm). In the portal hypertension group, the apparent vessel had a diameter of greater than 3 mm in only 20 patients (51%), but in 32 patients (82%) it was shown on Doppler examination to be a patent paraumbilical vein (i.e., hepatofugal venous signal). A patent paraumbilical vein on duplex Doppler sonography is therefore a specific sign of portal hypertension. The addition of Doppler imaging to conventional sonographic examination significantly increases the sensitivity for the diagnosis of portal hypertension by demonstration of a paraumbilical vein.