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At least 55 records · Page 3Linked to original sources

[Imaging of ciliated hepatic or biliary cysts. 4 cases].

Four patients with ciliated hepatic cysts, a rare and benign lesion, were examined between 1990 and 1994. Imaging features were compared to 12 previous cases. All lesions were revealed by US, and were hypoechoic in 3 cases, and anechoic in 1 case. All lesions were less than to 4 cm in diameter, and were well-defined, unilocular, isolated, and located in subcapsular areas, usually in the medial segment of the left lobe of the liver (3 cases). In one case, the cyst was found in the gallbladder wall. The lesions were low density on pre- and post-contrast CT scan (performed in 2 cases), strongly hyperintense on T2-weighted MR images (2 cases), and had a variable signal intensity on T1-weighted MR images. One patient underwent percutaneous guided biopsy but no diagnosis was obtained. None of the patients had preoperative diagnosis and all underwent surgery. Diagnosis was confirmed by histopathologic examination of the resected specimen. Ciliated hepatic cysts may be suspected in this study and in the literature. Diagnostic criteria are as follows: hypoechogenic mass less than 4 cm in diameter, located in the subcapsular area of the medial segment of the left lobe of the liver.

Adult↗

[Imaging of peripheral cholangiocarcinoma. Comparison with pathological anatomy].

OBJECTIVE: Peripheral cholangiocarcinoma is a rare malignant intrahepatic tumor which originates in the distal bile duct. Our purpose was to identify the imaging characteristics of peripheral cholangiocarcinoma and to establish a correlation with surgical and histopathologic findings. METHODS AND MATERIALS: The imaging data of 16 patients with proven cholangiocarcinoma were retrospectively reviewed by sonography in 13 cases, computed tomography in 13 cases, magnetic resonance imaging in 6 cases, and angiography in 10 cases and correlated with surgical and histopathologic findings. RESULTS: In most cases peripheral cholangiocarcinoma appeared as a single, large (> 10 cm), heterogeneous, and non encapsulated mass. On precontrast computed tomography, the lesions were mostly low density. Enhancement was moderate in the bolus phase and increased in the delayed scan. With magnetic resonance imaging, lesion signals were low intensity in T1-weighted images and variable intensity in T2-weighted images. On angiogram, lesions were often hypovascular. Associated features were frequently observed: portal encasement (69%), lobar atrophy or capsular retraction (43%), dilated intrahepatic bile ducts (30%), extension into the hepatic capsule (23%), and inferior vena cava extension (15%). Radiopathologic comparison showed that imaging modalities accurately identified vascular encasement, but underestimated extrahepatic tumor extension. CONCLUSION: In most cases, peripheral cholangiocarcinoma has a typical appearance which may be helpful in differentiating this disease from other intrahepatic tumors.

Adult↗

Liver metastases of digestive endocrine tumours: natural history and response to medical treatment.

BACKGROUND: Few data are available about the natural history of liver metastases of digestive endocrine tumours. Moreover, results of studies on treatment with intravenous chemotherapy, hepatic arterial chemoembolization and somatostatin analogues are conflicting. AIMS OF THE STUDY: To assess the progression of liver metastases of digestive endocrine tumours before antitumoral treatment, and to evaluate a stepwise therapeutic strategy in these patients. PATIENTS AND METHODS: 22 patients with histologically-confirmed liver metastases were studied. Primary tumours were carcinoids in nine, gastrinomas in five, non-functioning pancreatic tumours in six and calcitonin-secreting tumours in two patients. The progression of liver metastases was assessed according to the World Health Organization criteria in 10 patients before treatment, and during treatment in all patients. Intravenous (i.v.) chemotherapy with streptozotocin and 5-fluorouracil was used in patients with more than 25% progression in tumour size or with more than 50% liver involvement. Hepatic arterial chemoembolization was performed if i.v. chemotherapy failed, or as a first-choice treatment after 1993. The somatostatin analogues octreotide or lanreotide were used as a third-choice treatment. RESULTS: Progression (+90%, range 28-600%) of liver metastases was identified in the 10 patients studied before treatment, after a median follow-up of 11.5 months. Objective and minor responses were obtained in 2/10 patients (20%) and 1/10 patients (10%) receiving i.v. chemotherapy. Corresponding figures were 3/7 (43%) and 2/7 (29%) for hepatic arterial chemoembolization. No objective response was observed with somatostatin analogues, although 2 patients experienced a minor response. CONCLUSION: Untreated liver metastases of digestive endocrine tumours show an objective increase (their size approximately doubles after 1 year of follow-up). Among the currently available therapeutic modalities, hepatic arterial chemoembolization provides the highest response rates. An increase in patient survival as a result of this procedure remains to be determined.

Antineoplastic Agents↗

[A rare cause of obstructive jaundice: peripancreatic pseudoaneurysm].

We report the case of a 54-year-old-man with alcoholic calcified chronic pancreatitis complicated by jaundice and abdominal pain. Investigations (Doppler ultrasonography examination and computed tomography scan) showed peripancreatic pseudoaneurysm of the posterior and inferior pancreatico-duodenal artery and a dilatation of the common bile duct. Selective embolization of the pseudoaneurysm resulted in rapid regression of both jaundice and abdominal pain. Common bile diet compression is a rare complication of peripancreatic pseudoaneurysm. Selective embolization seems to be the first line treatment in this indication.

Aneurysm, False↗

[Hepatic angiomyolipoma simulating hepatocytic tumor. 3 cases].

Hepatic angiomyolipoma is a rare, benign, mesenchymal tumor. We report 3 cases of atypical angiomyolipomas simulating benign hepatic tumors in 3 women free of tuberous sclerosis (Bourneville's disease). Hepatic angiomyolipomas were solitary in 2 cases and multiple in one. At imaging, the 6 lesions were large (7 cm in mean diameter), mainly hypoechoic and heterogeneous. At CT, lesions did not contain fat and were hypervascular. At MR imaging, lesions were hypointense in 4 cases and isointense in one case on T1-weighted sequences, hyperintense and isointense on T2-weighted sequences in four and in one case respectively. Percutaneous biopsy, performed in 2 cases, did not provide a correct diagnosis. Histopathologic examination of the resected specimen showed angiomyolipomas with very low or lacking fat in all 3 patients. All lesions were positive with the HMB-45 antibody. In conclusion, hepatic angiomyolipoma with a low fat component may mimic other hepatic tumors. Diagnosis may be improved by using HMB-45 reactivity on the biopsy specimen.

Adenoma, Liver Cell↗

Abdominal aortic aneurysms: assessment with gadolinium-enhanced time-of-flight coronal MR angiography (MRA).

A prospective study was performed to evaluate the efficacy of a gadolinium-chelate-enhanced MR angiography (MRA) using a coronal acquisition in the preoperative assessment of aneurysms of the abdominal aorta (AAA). Twenty patients with AAA were explored with MR using a two-dimensional (2D) time-of-flight MRA technique with a coronal acquisition, before and after intravenous administration of 0.1 mmol/kg of a gadolinium-chelate. Gadolinium-chelate-enhanced MRA with a coronal acquisition decreased deleterious saturation effects within aorta and iliac arteries in 16 of 20 patients (80%) and improved the overall quality of the images of the upper and lower parts of the AAA (i.e. extent of the aneurysm). Furthermore, gadolinium-chelate-enhanced MRA with a coronal acquisition allowed a better differentiation between slow flow and mural thrombus. Gadolinium-chelate-enhanced MRA had a sensitivity of 100% and a specificity of 96% for evaluation of renal artery involvement, and a sensitivity of 93% and a specificity of 100% for iliac artery involvement. The results of this study show that gadolinium-chelate-enhanced MRA obtained with a coronal acquisition is efficacious for the preoperative assessment of AAA.

Aorta, Abdominal↗

Assessment of vascular involvement with magnetic resonance angiography (MRA) in Pancoast syndrome.

The purpose of this study was to evaluate the diagnostic value of MRA in determining vascular involvement in bronchogenic carcinoma with Pancoast syndrome. Six patients with Pancoast syndrome were investigated preoperatively by means of MRA. Following standard spin-echo MR imaging in the axial and coronal planes, two successive two-dimensional (2D) time-of-flight acquisitions were obtained in the axial plane, the first with venous, the second with arterial presaturation. MRA data were compared to angiographic data in four cases, and to surgical findings in all six cases. MRA demonstrated displacement (n = 2) and encasement (n = 2) of subclavian and/or brachiocephalic arteries, and encasement or occlusion of subclavian and/or right brachiocephalic vein (n = 3). Close correlation between MRA, angiography and surgery was obtained. These preliminary results suggest that MRA is a noninvasive diagnostic method complementary to MR imaging for detecting vascular involvement in bronchogenic carcinoma with Pancoast syndrome.

Adult↗

A bedside ultrasound sign ruling out pneumothorax in the critically ill. Lung sliding.

STUDY OBJECTIVES: To describe and evaluate an ultrasound pattern useful in the diagnosis of pneumothorax. DESIGN: Ultrasound examination of "lung sliding," a respiratory movement visible when investigating the chest wall. SETTING: The medical ICU of a university-affiliated hospital. PATIENTS: The study group included 43 proved pneumothoraces, either by chest radiograph (n = 40) or by CT (n = 3). The control group included 68 hemithoraces in which the absence of pneumothorax was proved by CT. INTERVENTION: Analysis of anterior chest wall in supine patients. MEASUREMENTS AND RESULTS: Feasibility was 98.1%. Disappearance of "lung sliding" was observed in 100% of 41 analyzable cases of pneumothorax vs 8.8% of the hemithorax without pneumothorax (6 of 68). In this series, sensitivity was 95.3%, specificity 91.1%, and negative predictive value 100% (p < 0.001). CONCLUSIONS: Ultrasound was a sensitive test for detection of pneumothorax, although false-positive cases were noted. The principal value of this test was that it could immediately exclude anterior pneumothorax.

Adult↗

[Hemoperitoneum caused by spontaneous rupture of hepatocellular carcinoma. Value and prognostic factors of hepatic artery embolization].

To assess efficiency and to determine prognostic factors in emergency embolization for intraperitoneal hemorrhage from hepatocellular carcinoma we retrospectively analyzed 12 consecutive procedures. In order to evaluate the extension of tumor thrombus in the intrahepatic portal system before embolization, a portal perfusion rate was defined as the relative patency of the segmental portal veins demonstrated at arteriography. Serum bilirubin level and portal perfusion rate were correlated with length of survival. Successful hemostasis was achieved in all patients. Mean length of survival was 149 days. Two patients are still alive 545 and 195 days, respectively, after the procedure. A significant correlation (p = 0.005) between portal perfusion rate and length of survival was obtained. There was no correlation between serum bilirubin level and prognosis. Emergency embolization is an effective treatment in patients with intraperitoneal hemorrhage from hepatocellular carcinoma. Prognosis depends of portal perfusion rate.

Aged↗

Radioanatomic study of the gastrocolic venous trunk.

The mode of formation, measurements and frequency of occurrence of the gastrocolic venous trunk were studied by the injection-corrosion technique in a series of 54 anatomic specimens and by the analysis of 50 CT studies in patients without hepatic or pancreatic disease. The gastrocolic trunk was found in 51 of the 54 anatomic specimens and in 27 of the 50 CT studies. The great variability in its formation, whether bipodal, tripodal or quadripodal, was noted. With a mean diameter of 4.9 mm, it opened into the anterior, right or antero-left aspects of the superior mesenteric v. at a mean distance of 15 mm below the inferior border of the spleno-mesenteric confluence. The value of preliminary CT assessment before an operation for portal hypertension or a pancreatic tumor or in the diagnosis of a splenic thrombosis is emphasised.

Aged↗

Dynamic Gd-DOTA-enhanced MR imaging of hepatic metastases from pancreatic neuroendocrine tumors.

The aim of this study was to determine the MR imaging features of hepatic metastases from pancreatic neuroendocrine tumors (HMPNT), and to assess their enhancement characteristics on dynamic gadolinium-chelate-enhanced MR imaging. Twelve consecutive patients with pathologically proven HMPNT underwent spin-echo (SE) and dynamic gradient-recalled echo (GRE) MR imaging before and after intravenous administration of a gadolinium-chelate (gadolinium tetraazacyclododecanetetraacetic acid; Gd-DOTA). MR examinations were performed prospectively and interpreted retrospectively in consensus by two radiologists. Fifty-five HMPNT were identified in matching anatomic sections on the different MR sequences and included in the study. On T1-weighted SE images, 45 HMPNT (82%) were hypointense and 10 HMPNT (18%) were isointense. On T2-weighted SE images 55 HMPNT (100%) were hyperintense. On GRE images obtained 20 s after Gd-DOTA injection, 41 HMPNT (75%) showed slight peripheral enhancement, and 14 HMPNT (25%) showed internal enhancement. Forty-four HMPNT (80%) were heterogeneous. On GRE images obtained 4 min after Gd-DOTA injection, 37 HMPNT (67%) showed peripheral enhancement, and 18 HMPNT (33%) showed a global and almost complete enhancement. Heterogeneity of enhancement was seen in all 55 HMPNT (100%). Although HMPNT exhibit a large spectrum of MR features, early enhancement and heterogeneity on dynamic GRE MR images are suggestive features of HMPNT.

Adult↗

Functional evaluation of normal and ischemic kidney by means of gadolinium-DOTA enhanced TurboFLASH MR imaging: a preliminary comparison with 99Tc-MAG3 dynamic scintigraphy.

The functional value of TurboFLASH MR imaging in the assessment of dynamic contrast enhancement and renal perfusion anomalies was evaluated in seven patients, who also underwent renal scintigraphy in baseline conditions. The basal renograms obtained from MAG-3 scintigraphy (mercapto acetyl triglycine, MAG3-S) and from Gd-DOTA-enhanced turboFLASH MRI were compared. After hydration, the protocol used consisted in breath-hold coronal turboFLASH acquisitions after IV bolus of Gd-DOTA (4 s every 20 s during 10 min) for MRI, and IV bolus of 370 MBq of 99mTc-MAG3 followed by 60 frames of 1 s and then 120 frames of 10 s for MAG3-S. Relative renal functions were computed for both methods by calculation of the integral of the uptake phase between the first and the second minute. Renograms exhibited 10 normal and 4 ischemic kidneys. There was a close correlation between the contrast enhancement of MRI and isotopic uptake in normal and ischemic kidneys. Global renograms of MRI correlated with MAG3-S (r = .82, p < .001) with similar curve shape and time to peak. Relative renal function of the right and left kidney were closely correlated in all patients (r = .98, p < .001), although there was a tendency for MR to overestimate MAG3-S evaluation in kidneys with severe basal dysfunction. Enhanced turboFLASH provides noninvasive assessment of renal perfusion in patients with renovascular disease. Accurate renograms are obtained with dynamic-enhanced MRI, but the relative renal function seems to be overestimated in low values of ischemic kidneys, and needs further comparative evaluation.

Adult↗

Focal hepatic masses: comparison of detection during arterial portography with MR imaging and CT.

PURPOSE: A prospective study was performed to compare the sensitivity and specificity of magnetic resonance (MR) imaging and computed tomography (CT) both performed during arterial portography in depicting focal hepatic masses. MATERIALS AND METHODS: Eleven patients with 31 pathologically proved focal hepatic masses were prospectively evaluated. MR arterial portography was performed with 4 mL of a 0.5 mmol/kg solution of gadolinium tetraazacyclododecanetetraacetic acid (DOTA) injected through a catheter into the superior mesenteric artery during multisection gradient-echo imaging. RESULTS: MR arterial portography depicted 29 of the 31 masses (sensitivity, 94%). CT arterial portography depicted 27 of the 31 masses (sensitivity, 87%). Two masses not depicted with either CT or MR had a diameter of 3 and 7 mm, respectively. Neither MR nor CT demonstrated a false-positive finding (specificity, 100%). The difference in sensitivity and specificity between the two techniques was not statistically significant. CONCLUSION: MR arterial portography does not enable detection of significantly more focal hepatic masses than does CT arterial portography.

Female↗

Enlarged mediastinal lymph nodes in bronchogenic carcinoma: assessment with dynamic contrast-enhanced MR imaging. Work in progress.

PURPOSE: To determine whether dynamic contrast material-enhanced magnetic resonance (MR) imaging can help differentiate between malignant and benign mediastinal lymph nodes (MLNs) in bronchogenic carcinoma. MATERIALS AND METHODS: Nine patients with biopsy-proved lung carcinoma underwent dynamic contrast-enhanced MR imaging before undergoing thoracic surgery. MR studies included spin-echo, electrocardiographically gated axial and coronal sequences and transaxial gradient-echo breath-hold sequences, which were performed after administration of a bolus of gadoterate meglumine. The enhancement curves were established on the basis of mean signal intensities from regions of interest at the level of tumor and the enlarged MLN. MR images were compared with pathologic specimens obtained at surgical resection. RESULTS: Metastatic MLNs exhibited their peak enhancement at 60-80 seconds, with a slow decrease until 6 minutes. Granulomatous and anthracotic lymph nodes displayed a slight enhancement, with no peak within 6 minutes (P < .01). CONCLUSION: Dynamic contrast-enhanced MR images may provide informative data about the nature of enlarged MLNs in the preoperative assessment of lung carcinoma. Further studies are needed to investigate its usefulness in clinical practice.

Aged↗

Hepatic adenoma: MR findings in 51 pathologically proved lesions.

PURPOSE: To describe the magnetic resonance (MR) imaging features of hepatic adenoma and correlate these findings with histopathologic findings. MATERIALS AND METHODS: MR findings of 51 pathologically proved hepatic adenomas in 29 consecutive patients were retrospectively analyzed. T1- and T2-weighted spin-echo (SE) images were obtained in all patients, and contrast material-enhanced MR images were obtained in 16 patients. RESULTS: At pathologic analysis, a peripheral rim, observed in 16 (31%) hepatic adenomas, corresponded to pseudocapsule, and tumor heterogeneity, observed in 26 (51%) lesions, corresponded to hemorrhagic necrosis and peliosis. Hyperintensity on T1-weighted SE images was observed in 30 (59%) adenomas; 10 (67%) of 15 hepatic adenomas were hyperintense on contrast-enhanced gradient-echo images, and 13 (45%) of 29 were hyperintense on delayed contrast-enhanced T1-weighted SE images. CONCLUSION: Presence of a peripheral rim, heterogeneity, and hyperintensity are common features of hepatic adenoma.

Adenoma↗