Budd-Chiari syndrome: dynamic CT

A retrospective multi-institutional study was carried out on a series of 38 patients with histologically proved Budd-Chiari syndrome: Five patients had acute disease, and 33 had subacute or chronic disease. All patients underwent dynamic CT scanning. Angiography was performed in 20 cases, inferior cavography in 22, and wedge-hepatic venography in 16. In all acute cases, CT showed global liver enlargement with diffuse hypodensity on plain scans and patchy enhancement after contrast material injection. Thrombosis of the three main hepatic veins was always demonstrated. In subacute or chronic disease, plain CT scans showed abnormalities of liver morphology and hypodensity either in atrophic areas (19 cases) or in the periphery of the liver (eight cases). With dynamic CT, patchy enhancement was present in 28 cases. Correlation with angiography in 15 cases revealed a normal portal blood flow in enhanced areas and an inversed portal blood flow in atrophic areas. Different morphologic and enhancement patterns on CT scans could be related to the direction of portal blood flow, which changes with different stages of Budd-Chiari syndrome.

[Pancreatic cystadenomas. Pitfalls and limitations of radiologic diagnosis]

Pancreatic cystadenoma (CA) are rare tumors. According to the classification described by Compagno and Oertel, microcystic and macrocystic CA are differentiated. The former is a benign tumor with slow growth, but the latter has a malignant potential. According to the literature, these tumors may be differentiated on the basis of US and CT findings in a high percentage of cases. We report a series of 11 cases (5 microcystic CA, 4 mucinous CA, 1 leiomyoblastoma and 1 adrenal cyst) representing all cases of radiologically suspected CA and all cases of histologically proved CA. A correct diagnosis of microcystic CA was possible in 2 out of 5 cases, and in 3 out of 4 cases of mucinous CA. The 2 extra-pancreatic tumors were misinterpreted as mucinous CA. No patient had a false positive diagnosis of microcystic CA. The diagnosis of mucinous CA was made in 7 cases, but only 3 were true positives. There was 1 false negative of mucinous CA. In other cases, laparotomy and resection are mandatory as sonography and CT cannot accurately detect malignancy or differentiate pancreatic CA from adjacent sites tumors.

[Left inferior vena cava. Ultrasonic diagnosis]

A case of left infrarenal vena cava is detected by ultrasonography and confirmed inferior cavography. Embryogenesis of the inferior vena cava aids understanding of this type of congenital anomalies. Ultrasonographic diagnosis is based on the absence of right infrarenal vena cava, the presence of a vascular structure left to the abdominal aorta an a normal hepatic segment of inferior vena cava.

Budd-Chiari syndrome: US evaluation

Twelve patients with proved Budd-Chiari syndrome (eight acute and four chronic cases) were examined, using real-time ultrasonography (US). In all acute cases, US study showed at least one hepatic vein with findings suggestive of the syndrome, such as stenosis, dilatation, thick wall echoes, thrombosis, abnormal course, or extrahepatic anastomosis. In chronic cases, hepatic veins were usually not visible. Modifications of liver morphology were present in all patients except those with recent onset of the disease. Caudate lobe hypertrophy was present in only six cases. US study is therefore the procedure of choice for initial diagnosis of acute Budd-Chiari syndrome. Pitfalls were the failure to detect two caval thromboses and one hepatic vein web. Cavography should still be performed systematically, but hepatic phlebography is useful in selected cases only.

Sonographic and computed tomographic evaluation of intrahepatic calculi

Intrahepatic calculi in non-Asian patients were studied by sonography and computed tomography (CT). Three patients were studied by CT cholangiography also. In two cases, the calculi were consecutive to Caroli disease, and in two others, the biliary stones were formed proximal to a stenosis of a previous surgical anastomosis. Five patients spontaneously developed intrahepatic calculi. All sonograms were abnormal. Image specificity was good, even when bile ducts were not dilated, if appropriate technique allowed identification of a double-arc-shadow pattern. Sonography strongly suggested the diagnosis in eight patients and was nonspecific in only one. On CT, calculi had various densities, and they were not visible in two patients. CT cholangiography was not particularly helpful. Finally, CT added little more information when performed after sonography. Both examinations strongly underestimate the number of stones, and direct cholangiography remains indicated if surgery is planned.

[Magnetic resonance imaging in the exploration of hepatic masses]

Exploration was conducted by magnetic resonance imaging (MRI) at 0.15 T in 33 patients with hepatic masses, including 18 with malignant tumors, 11 with benign tumors and 4 with non-tumoral masses. All tumors appeared hyperintensive in relation to liver on images acquired by long TR spin echos (SE) and all, except for one fatty tumor, appeared hypointense in relation to liver on images acquired in inversion-recuperation (IR). The study seemed to provide data demonstrating that MRI at 0.15 T enables visualization of hepatic masses with a degree of precision that approaches that of other imaging methods. Tumors of the small size of the order of a centimetre can be detected. Tumor outlines and vascular relations are clearly demonstrated without use of contrast. Characterization of masses is still insufficient since the simple play of contrasts between tumor, parenchyma and vessels does not allow differentiation of malignant from benign tumors, nor the identification of a given histologic type.