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A Sibert

Publications and source records attributed to A Sibert.

64 records · Page 4Linked to original sources
PubMedDate not supplied

Intrahepatic bile duct dilatation secondary to hepatocellular carcinoma: CT features in 10 patients.

BACKGROUND: To determine the computed tomographic (CT) features of bile duct obstruction secondary to hepatocellular carcinoma (HCC). METHODS: CT examinations of 10 patients (mean age, 58 years) with bile duct obstruction secondary to HCC were retrospectively reviewed. RESULTS: All tumors were intrahepatic. Eight tumors were well-delineated and two were ill-defined. The largest diameters of tumor ranged from 1.5-6.0 cm (mean, 3.6 cm). All tumors were hypodense before contrast and did not contain calcification. After contrast, four tumors became hypodense, three were isodense, and three were hyperdense to the liver. No tumor demonstrated encapsulation. Diffuse intrahepatic bile duct dilation was observed in seven patients. One patient had extrahepatic bile duct dilatation. Localized bile duct dilatation was observed in three patients, in the hemi-liver which contained the tumor. No tumor invaded the portal vein. CONCLUSION: Although rare, HCC should be included in the differential diagnosis of bile duct obstruction. This diagnosis should be suggested in patients with bile duct obstruction when CT shows an associated intra- or extrahepatic mass. Our results suggest that HCC responsible for bile duct obstruction is remarkable for the absence of encapsulation.

Adult↗
PubMedDate not supplied

Bile duct involvement in hepatocellular carcinoma: MR demonstration.

BACKGROUND: To determine the magnetic resonance (MR) features of hepatocellular carcinoma (HCC) with associated bile duct involvement. METHODS: MR examinations of six patients (mean age, 62 years) demonstrating bile duct involvement due to HCC were retrospectively reviewed and compared to surgical and pathologic findings. RESULTS: Three of the tumors were solitary, and three were multifocal. In two patients, MR showed direct biliary duct invasion by tumor. On T1-weighted MR images, four tumors were hypointense compared to the liver and two were isointense. On T2-weighted MR images, four tumors were hyperintense, and two were isointense. The two tumors studied with dynamic T1-weighted MR images obtained after intravenous administration of a gadolinium chelate, displayed enhancement similar to that of the liver. There was no evidence of a tumor capsule on either unenhanced or enhanced MR images. Intrahepatic bile duct dilatation was seen in five patients. The extrahepatic bile duct was normal in all cases. CONCLUSION: Although rare, HCC should be included when considering the etiology of intrahepatic bile duct obstruction. Imaging features suggestive of the diagnosis by MR include intrabiliary tumor or bile duct obstruction with an associated hepatic mass.

Aged↗
PubMedDate not supplied

MR imaging of intrahepatic cholangiocarcinoma.

BACKGROUND: The purpose of this study was to determine the magnetic resonance (MR) features of intrahepatic cholangiocarcinoma. METHODS: MR imaging studies of seven cases of pathologically proven intrahepatic cholangiocarcinoma were retrospectively reviewed. RESULTS: On MR images the tumors presented as a single mass (N = 5) or multiple nodules (N = 2), as well-delineated (N = 5) or ill-defined (N = 2), and as nonencapsulated (N = 7). Mean tumor diameter ranged from 6-14 cm (mean, 10 cm). On T1-weighted (TR/TE = 400-600/10-17 msec) images, the tumors were hypointense compared to the liver. The five tumors studied with dynamic MR imaging showed progressive centripetal filling-in after intravenous administration of a gadolinium chelate. On T2-weighted (TR/TE = 2000-2500/80-100 msec) images, all tumors were hyperintense compared to the liver; five were markedly hyperintense and two moderately hyperintense. Vascular encasement, bile duct dilatation within the tumor, and central scar were depicted on MR images in four, three, and two tumors respectively. CONCLUSION: The typical MR appearance of intrahepatic cholangiocarcinoma is a large well-delineated nonencapsulated tumor associated with intrahepatic venous encasement.

Adult↗
PubMedDate not supplied

Dynamic gadolinium-DOTA-enhanced MR imaging at 1.0 T. Value in the differentiation of hepatic tumors.

A prospective study was performed to determine the value of dynamic gadolinium-tetraazacyclododecane-tetraacetic acid (Gd-DOTA)-enhanced magnetic resonance (MR) imaging at 1.0 T, using a gradient-echo (GRE) technique, in the differentiation of hepatic tumors. Fifty patients with hemangiomas (n = 14), focal nodular hyperplasia (n = 4), and malignant tumors of the liver (n = 32) underwent GRE MR imaging at 1.0 T before and repeatedly for 4 minutes after intravenous bolus administration of Gd-DOTA. The diagnoses were proved by histology or follow-up examination. On unenhanced GRE images, hemangiomas had a significantly lower tumor-to-liver contrast-to-noise (C/N) ratio (-14.74 +/- 4.49) than did the other tumors (-6.96 +/- 5.49) (p < 0.02), and benign tumors had a significantly lower C/N ratio (-12.43 +/- 5.99) than did malignant tumors (-7.29 +/- 5.71) (p < 0.05). On contrast-enhanced images, hemangiomas had a significantly lower C/N ratio (-17.60 +/- 6.90) than did the other tumors (-5.07 +/- 12.12) (p < 0.05) in the early phase. During the delayed phase, hemangiomas had a significantly higher C/N ratio (3.90 +/- 3.81) than did the other tumors (-4.85 +/- 6.51) (p < 0.01), and benign tumors had a significantly higher C/N ratio (3.21 +/- 3.65) than did malignant tumors (-5.56 +/- 6.56) (p < 0.001). Our data suggest that dynamic Gd-DOTA-enhanced MR imaging at 1.0 T provides useful information to differentiate between benign and malignant hepatic tumors, and to distinguish hemangiomas from the other tumors.

Adult↗
PubMedDate not supplied

Cystic tumors of the pancreas: dynamic CT studies.

OBJECTIVE: Our retrospective study was performed to reassess the common dynamic CT manifestations of cystic tumors of the pancreas and to determine whether they might allow the differentiation between benign and malignant tumors. MATERIALS AND METHODS: Dynamic CT examinations of 19 patients with 20 cystic tumors of the pancreas, including 7 serous cystadenomas, 3 benign mucinous cystadenomas, 5 mucinous cystadenocarcinomas, 3 mucin-producing duct ectasias, and 2 papillary cystic epithelial neoplasms, were retrospectively reviewed. The examinations were obtained with 4 to 5 mm collimation with intravenous injection of 120-130 ml of contrast agent. RESULTS: Calcifications were found only in benign tumors (seven serous cyst-adenomas). Internal septations were found in benign and malignant tumors (seven serous cystadenomas, three benign mucinous cystadenomas, three mucinous cystadenocarcinomas). Solid excrescences within cystic cavities were found only in malignant tumors (two mucinous cystadenocarcinomas, two mucin-producing duct ectasias). Dynamic CT features allowed the distinguishing of serous cystadenomas from other cystic tumors and mucin-producing duct ectasias from other mucinous tumors. Dynamic CT features did not permit differentiation between benign mucinous cystadenomas, mucinous cystadenocarcinomas, and papillary cystic epithelial neoplasms. CONCLUSION: The review suggests that dynamic CT findings are useful to differentiate (a) serous cystadenomas and mucin-producing duct ectasias from other cystic tumors of the pancreas and (b) benign from malignant tumors. Such differentiation has impact on patient management.

Aged↗
PubMedDate not supplied

Contrast-enhanced fast MRI in differentiating brain toxoplasmosis and lymphoma in AIDS patients.

OBJECTIVE: Dynamic contrast-enhanced MRI was used to investigate space-occupying lesions of the brain in 22 AIDS patients without prior neurologic disease. Final diagnoses were toxoplasmosis in 13 patients (19 lesions), primary lymphoma in 7 patients (9 lesions), and both diseases in two (2 lesions, respectively). MATERIALS AND METHODS: Dynamic contrast-enhanced MRI was done by using a heavily T1-weighted GE sequence (TR/TE 100/5, 80 degrees flip angle) performed before and repeatedly for a period of 15 min after intravenous bolus injection of Gd-DOTA (0.1 mmol/kg). Signal enhancement of the lesions and normal brain was measured as the difference of signal intensity before and after intravenous administration of contrast medium. RESULTS: Lymphomas displayed significantly greater enhancement (mean 67%; SD 18%) than toxoplasmosis did (mean 34%; SD 16%; p < 0.001) on FLASH images. The enhancement ratios of the two lesions were significantly (p < 0.01) different between 30 and 600 s after injection. The difference between toxoplasmosis (mean 49%; SD 17%) and lymphoma (mean 69%; SD 26%) enhancement ratios on delayed SE images was less significant (p = 0.04). CONCLUSION: Preliminary evidence suggests that dynamic sequences increase the specificity of MR in distinguishing between toxoplasmosis and lymphoma, and this has important clinical implications.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Scrotal trauma. Report of 33 cases].

We report a serial case study of 33 patients from May 1980 to November 1990 presenting a scrotal contusion. In 2/3 of cases, the physical examination showed a scrotal oedema or an hematocele. Ultrasonography showed a testicular injury while clinical examination was subnormal in 2 patients. In the other cases, ultrasonography showed an hematocele without asserting in all cases the traumatic rupture of the tunica albuginea. 27 patients have been surgically explored: 14 ruptures of the testicle, 3 intratesticular haematoma, 3 scrotal open traumatic injuries, and 7 extratesticular haematoma. Only 3 orchidectomies were required for the 6 patients who have not been explored surgically, the testis was normal at one month. The follow-up of these young patients is difficult, 11 had been seen again at 1 month. At long term follow-up, three patients had been seen at 1, 3 or 6 years without testicular after-effects.

Adolescent↗
PubMedDate not supplied

[Osseous hydatidosis of the pelvic girdle. Contribution of computerized tomography and ultrasonics. Apropos of 3 cases].

Three cases of bone hydatidosis of pelvis with invasion of soft tissues provided data on the effectiveness of CT scan and ultrasound imaging for diagnosis, evaluation of extension and follow up surveillance of this affection. Two of the three patients treated medically were followed up by review CT scan and ultrasound examinations. The two techniques were found to be effective for detecting recurrence and for surveillance of hydatid lesions of soft tissues during medical therapy.

Adult↗