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P Soyer

Publications and source records attributed to P Soyer.

At least 55 records · Page 3Linked to original sources
PubMed1997

Renal cell carcinoma of clear type: correlation of CT features with tumor size, architectural patterns, and pathologic staging.

The purpose of this study was to report the CT findings of renal cell carcinoma of clear type (RCCCT) and to determine if there are characteristic morphologic features in RCCCT with respect to tumor size, architectural patterns, and pathologic stage. The CT scans of 35 patients with RCCCT were reviewed retrospectively. The CT findings (tumor size, attenuation patterns, presence of calcifications, encapsulation, margins of neoplasms, venous involvement by neoplasms) were correlated with tumor size, architectural patterns, and pathologic staging. Of the 35 neoplasms, 28 (80 %) were solid, 4 (11 %) were papillary, and 3 (9 %) were cystic. Complete encapsulation was more frequent in lower pathologic stages (40 % in stages 1 and 2 vs 0 % in stages 3 and 4; p < 0.05). Venous involvement was less frequent with completely encapsulated neoplasms (0 of 10, 0 %) than with incompletely or nonencapsulated neoplasms (8 of 25, 32 %; p < 0.05). Encapsulated RCCCT are more likely to have lower pathologic stage. Nonencapsulated neoplasms are more likely to have a higher pathologic stage.

Adenocarcinoma, Clear Cell↗
PubMed1997

Computed tomography of complications of lung transplantation.

In spite of improvements in single or double lung transplantation (LT) technique, complications after LT are not uncommon; the most frequent ale anastomotic complications, infections and rejection (acute or chronic). Early detection of complications of LT allows the optimal therapeutic option to be taken, yielding decreased morbidity and mortality. In some cases, CT plays a key role in early detection of several complications of LT that may not be depicted with other diagnostic modalities, so that knowledge of their CT features is important. In this pictorial review, the authors describe the spectrum of CT features of the complications of LT (including reimplantation response, mechanical problems, acute and chronic rejection, infection, lymphoproliferative disorders, recurrence of the initial disease and complications involving the pleura and the anastomotic sites). In addition, the authors analyze the value of CT compared to that of the other available modalities for the detection of complications of LT.

Adult↗
PubMed1997

T1-weighted spoiled gradient-echo MR imaging of focal hepatic lesion: comparison of in-phase vs opposed-phase pulse sequence.

The goal of our prospective study was to compare quantitatively and qualitatively in-phase and opposed-phase T1-weighted breath-hold spoiled gradient-recalled-echo (GRE) MR imaging technique for imaging focal hepatic lesion. Thirty-eight patients with 53 focal hepatic lesions had in-phase (TR = 12.3 ms, TE = 4.2 ms) and opposed-phase (TR = 10.1 ms, TE = 1.9 ms) GRE (flip angle = 30 degrees , bandwidth +/- 32 kHz, matrix size 256 x 128, one signal average) MR imaging at 1.5 T. Images were analyzed quantitatively by measuring the lesion-to-liver contrast and for lesion detection. In addition, images were reviewed qualitatively for lesion conspicuity. Quantitatively, lesion-to-liver contrast obtained with in-phase (3. 22 +/- 1.86) and opposed-phase pulse sequence (3.72 +/- 2.32) were not statistically different (Student's t-test). No difference in sensitivity was found between in-phase and opposed-phase pulse sequence (31 of 53, sensitivity 58 % vs 30 of 53, sensitivity 57 %, respectively). Two lesions not seen with opposed-phase imaging were detected with in-phase imaging. Conversely, one lesion not seen on in-phase imaging was detected on opposed-phase imaging so that the combination of in-phase and opposed-phase imaging yielded detection of 32 of 53 lesions (sensitivity 60 %). Qualitatively, lesion conspicuity was similar with both techniques. However, in-phase images showed better lesion conspicuity than opposed-phase images in 9 cases, and opposed-phase images showed better lesion conspicuity than in-phase images in 7 cases. No definite advantage (at a significant level) emerged between in-phase and opposed-phase spoiled GRE imaging. Because differences in lesion conspicuity and lesion detection may be observed with the two techniques in individual cases, MR evaluation of patients with focal hepatic lesion should include both in-phase and opposed-phase spoiled GRE imaging.

Adult↗
PubMed1997

Intraoperative and laparoscopic sonography of the liver.

Intraoperative sonography is an important aid in the decision making process during open surgery because it can detect additional small liver tumours that may not be depicted preoperatively, even with the use of modern non invasive imaging modalities. A continued important role of intraoperative sonography is to determine hepatic anatomy, allowing for safer and easier hepatic surgery with increased parenchymal preservation. Intraoperative sonography is also used for monitoring cryogenic ablation of hepatic tumour. To overcome the inherent limitations of laparoscopic surgery, laparoscopic sonography can now be used to provide information not available during laparoscopy or laparoscopic surgery alone. In this article, the authors present the most recent techniques for intraoperative sonography. Also they emphasize the important role of intraoperative sonography and laparoscopic sonography in the surgical decision-making process in patients with hepatic or biliary disease and report the most recent advances in intraoperative sonography with respect to the treatment of hepatic tumours. Finally, they try to look forward at the possible use for intraoperative technologies that are now in their early stages.

Hepatectomy↗
PubMed1997

Transjugular liver biopsy with an automated device.

PURPOSE: To determine the potential for use of an automated device for transjugular liver biopsy. MATERIALS AND METHODS: In 29 consecutive patients with liver dysfunction in whom percutaneous transperitoneal biopsy was contraindicated because of thrombocytopenia, severe coagulopathy, or marked ascites, transjugular liver biopsy was performed with an 18-gauge automated device. Histopathologic specimens were quantitatively and qualitatively analyzed. Complications related to the biopsy procedure were noted. RESULTS: In all patients, an adequate biopsy specimen (mean length, 12.0 mm +/- 5.5; range, 5.0-20.0 mm) was obtained during a single pass. In all tissue samples, a confident histopathologic diagnosis was made. Additional information was obtained in 15 patients with cirrhosis who had coexisting diffuse hepatic disease. No complications related to the procedure were noted. CONCLUSION: Use of an automated biopsy device is recommended for transjugular liver biopsy, as it enables safe acquisition of high-quality hepatic tissue samples.

Biopsy, Needle↗
PubMed1997

Hepatic cavernous hemangioma: appearance on T2-weighted fast spin-echo MR imaging with and without fat suppression.

OBJECTIVE: The goals of our study were to define the morphologic appearance of cavernous hemangioma of the liver on T2-weighted fast spin-echo MR imaging and to determine if the use of fat suppression may quantitatively and qualitatively modify the MR imaging appearance of cavernous hemangioma. SUBJECTS AND METHODS: Twenty-six patients with cavernous hemangiomas of the liver were prospectively studied with T2-weighted MR imaging with a fast spin-echo technique with and without fat suppression. Thirteen patients had known hemangiomas for more than 2 years, with no change in size or morphology during this period. The remaining 13 patients had diagnoses based on dynamic CT and sonography and an absence of change in the morphology and size of their lesions during follow-up of more than 6 months (range, 6-12 months) after the MR imaging studies. Values for signal intensity and contrast-to-noise (C/N) ratios in cavernous hemangiomas that were obtained with and without fat suppression were compared. Images were qualitatively analyzed separately at identical level and window settings by two interpreters for morphologic features of cavernous hemangiomas. RESULTS: No significant difference was found between signal intensity values obtained using the fat-suppressed fast spin-echo MR imaging technique (5.62 +/- 1.14 [SD]) and those obtained without fat suppression (5.51 +/- 1.23). Values for C/N ratios obtained with the fat-suppressed fast spin-echo MR imaging technique (20.13 +/- 7.63) were significantly superior to those obtained without fat suppression (16.59 +/- 5.31) (p < .001). On T2-weighted fast spin-echo MR imaging without fat suppression, 100% of cavernous hemangiomas were hyperintense relative to the spleen, 90% had well-defined and sharp margins, 55% were isointense to CSF, and 76% were homogeneous. Without fat suppression, 34% of cavernous hemangiomas showed the combination of isointensity to CSF, well-defined margins, and homogeneity. On T2-weighted fast spin-echo MR imaging with fat suppression, all cavernous hemangiomas showed this same combination of features. CONCLUSION: Seventy-six percent of hepatic cavernous hemangiomas were homogeneous on T2-weighted fast spin-echo MR imaging, and 55% were isointense to CSF. However, only 34% of hepatic cavernous hemangiomas showed typical features. Although fat suppression significantly increased the C/N ratio of cavernous hemangiomas of the liver, fat suppression did not affect their morphologic appearance on T2-weighted fast spin-echo MR imaging.

Female↗
PubMed1997

Non-breath-hold fast spin-echo versus breath-hold fast spin-echo and spoiled gradient-recalled echo MR imaging in the detection of hepatic tumors: correlation with surgical findings.

OBJECTIVE: Our objective was to compare the sensitivity of non-breath-hold T2-weighted fast spin-echo with and without fat suppression, breath-hold T2-weighted fast spin-echo without fat suppression, and spoiled gradient-recalled echo (GRE) MR imaging for detecting hepatic tumors using surgical findings as the standard of reference. SUBJECTS AND METHODS: Eighteen patients with 36 surgically proven hepatic tumors had non-breath-hold T2-weighted fast spin-echo (6000/117 [TR/effective TE; echo train length, 16) MR imaging with and without fat suppression, breath-hold T2-weighted fast spin-echo MR imaging (2700/105; echo train length, 20), and spoiled GRE images (10.1/1.9; flip angle, 30 degrees) obtained before and after injection of a gadolinium chelate. Images were analyzed separately by two independent readers, with disagreements resolved by consensus reading. RESULTS: Non-breath-hold T2-weighted fast spin-echo MR imaging with and without fat suppression depicted 22 (61%; 95% confidence interval [CI], 43-77%) and 20 (56%; 95% CI, 37-72%) of 36 hepatic tumors, respectively. Breath-hold T2-weighted fast spin-echo imaging allowed detection of 19 (53%; 95% CI, 35-69%) of 36 hepatic tumors. Unenhanced and gadolinium chelate-enhanced spoiled GRE images allowed depiction of 18 (50%; 95% CI, 33-67%) and 29 (81%; 95% CI, 63-91%) of 36 hepatic tumors, respectively. Gadolinium chelate-enhanced spoiled GRE images allowed depiction of significantly more hepatic tumors than any of the other pulse sequences. CONCLUSION: Gadolinium chelate-enhanced spoiled GRE imaging is more sensitive than T2-weighted MR imaging obtained with a breath-hold or a non-breath-hold technique.

Contrast Media↗
PubMed1997

Nontumorous hepatic pseudolesion around the falciform ligament: prevalence on gadolinium chelate-enhanced MR examination.

OBJECTIVE: Our objective was to determine the prevalence of nontumorous hepatic pseudolesions seen around the falciform ligament on dynamic spoiled three-dimensional (3D) gradient-recalled echo (GRE) MR imaging obtained during i.v. injection of a gadolinium chelate. SUBJECTS AND METHODS: The gadolinium chelate-enhanced spoiled 3D GRE examinations of the liver of 103 patients were prospectively analyzed by two readers for the presence of a nontumorous hepatic pseudolesion around the falciform ligament to determine the prevalence of this finding. For all pseudolesions, pathologic examination or follow-up imaging studies excluded true tumors. RESULTS: A total of 15 nontumorous hepatic pseudolesions were found on 13 (13%) of 103 examinations. The size of pseudolesions ranged from 5 to 15 mm (mean, 9 mm). Twelve pseudolesions were located in segment IV, and three were in segment III. On two MR examinations, two pseudolesions (one in segment IV and one in segment III) were found. Fourteen (93%) of 15 pseudolesions were seen during the arterial phase of the bolus injection. All pseudolesions (100%) were seen during the portal phase, and one pseudolesion (7%) remained visible during the equilibrium phase. The presence of true tumors was excluded in one case by pathologic examination and in twelve cases by follow-up imaging examinations. CONCLUSION: Nontumorous hepatic pseudolesions around the falciform ligament are not rarely seen on gadolinium chelate-enhanced spoiled 3D GRE examinations. Thus, recognition of these pseudolesions is crucial because they may be misinterpreted as true tumors.

Adult↗
PubMed1997

Intrahepatic cholangiocarcinoma: the role of imaging in detection and staging.

Intrahepatic cholangiocarcinoma can be divided into two basic categories: hilar and peripheral forms. This distinction has important implications in imaging evaluation, treatment, and prognosis. Cholangiocarcinoma often requires multiple imaging modalities for proper evaluation of potential resectability. In this review, we outline the role of CT, MR, ultrasound, cholangiography, and angiography in the evaluation of cholangiocarcinoma. We also describe newer techniques such as CT angiography, CT cholangiography, MR angiography, and MR cholangiography, and look at the possible future roles of these techniques.

Angiography↗
PubMed1997

MR imaging of the liver. Technique.

Multiple techniques are currently available for MR imaging of the liver. Optimization of MR pulse sequences is a critical issue in MR imaging of the liver because image quality and diagnostic value greatly depend on imaging protocol. Imaging protocols vary among institutions because of differences in equipment and because of the absence of consensus regarding the most appropriate sequence. This article presents an overview of the basic MR sequences, highlights the most recent advances, and presents the more promising future trends in MR imaging of the liver.

Artifacts↗
PubMed1997

[Can primary kidney clear cell adenocarcinoma be differentiated from kidney metastasis with computed tomography?].

PURPOSE: To determine if CT scan provides morphologic criteria allowing differentiation between primary renal cell cancer of the clear type (PRCCCT) and renal metastasis (RM). MATERIALS AND METHODS: Twenty cases of PRCCCT and 20 cases of RM from various origins (excluding lymphomatous origin) were retrospectively analyzed by two independent readers. CT scans were evaluated with respect to tumor size, shape, location and number of tumors, encapsulation, contour sharpness, presence of calcification, and extrarenal involvement by tumor. RESULTS: A tumor size > 3 cm was more frequently seen in PRCCCT than in RM (100% vs 70% respectively, P < .05). Rounded shape was more frequent in PRCCCT than in RM (90% vs 50% respectively, P < .01). Encapsulation was more frequent in PRCCCT than in RM (70% vs 10%, P < .01, respectively). Calcification was depicted only in PRCCCT (35% vs 0%, P < .01). Enlarged perirenal lymph nodes were less frequent in PRCCCT than in RM (20% vs 55% respectively, P < 0.05). CONCLUSION: Results of our study show that a constellation of morphologic features suggest the diagnosis of PRCCCT rather than that of RM. Our study suggests that calcification is highly specific for the diagnosis of PRCCCT. However, percutaneous biopsy remains indicated to ascertain the diagnosis.

Adenocarcinoma, Clear Cell↗
PubMed1997

[Radiological aspects of hepatic tuberculoma. 3 cases].

Localized macronodular tuberculosis of the liver is rare. Tuberculous involvement of the liver is usually a diffuse process. We report 3 cases in which clinical and imaging features suggested the diagnosis of macronodular hepatic tuberculoma which was pathologically confirmed by percutaneous biopsy. In the first case, abdominal CT-scan showed a noncalcified hypodense nodular lesion in segment IV of the liver with an enhancing peripheral rim. In the second case, ultrasound showed 4 homogenous hypoechoic hepatic nodules. In the third case, a nodule was incidentally identified in segment VII of the liver. The lesion was hypoechoic with ultrasound, hypodense without enhancement on CT-scan, and hyperintense on both T1- and T2-weighted MR imaging. After percutaneous biopsy, pathologic examination showed peripheral granulomous lesions in all patients with central caseous necrosis consistent with tuberculosis in two patients despite a negative for Zielh stain. Specific M. tuberculosis culture was positive in the first patient, negative in the second patient, and was not performed in the third patient. Appropriate treatment resulted in disappearance of hepatic lesions on follow-up imaging examinations. These 3 cases show that clinical and imaging features of hepatic tuberculoma are not specific and that percutaneous biopsy of lesions provides a definite diagnosis.

Female↗
PubMed1996

CT during arterial portography.

CT during arterial portography (CTAP) is based on portal enhancement of the liver by infusion of contrast material through the superior mesenteric or splenic artery. This technique provides high degrees of enhancement of the portal vein and intrahepatic vessels, allowing reliable segmental localisation of tumours and accurate assessment of relationships between tumours and intrahepatic vessels. Because of its invasiveness, CTAP must be limited to patients for whom non-invasive preoperative imaging suggests resectable tumour. In the majority of cases, CTAP is performed in patients with hepatic metastases from colorectal cancer, but other types of hepatic tumour (either primary or secondary) and pancreatic tumour may be an indication for CTAP. Visualisation of non-tumorous perfusion defects is a limitation of this technique, but such defects have been well described and have characteristic locations and appearance. In difficult cases, correlation with sonographic, CT and MRI findings helps characterise portal perfusion defects. CTAP is the most sensitive technique for the detection of intrahepatic tumours, and the recent use of spiral technology shows promise in the performance of CTAP. CTAP data can be viewed as multiplanar and three-dimensional reconstructions that allow preoperative planning of the extent of resection and determination of the volume of the remaining liver after resection.

Carcinoma, Hepatocellular↗
PubMed1996

Magnetic resonance imaging of the spleen: influence of the dose of a gadolinium chelate on the degree of parenchymal enhancement.

RATIONALE AND OBJECTIVES: We examined how the dose of an intravenous (i.v.) gadolinium chelate (gadoterate meglumine) would affect the degree of splenic enhancement on magnetic resonance (MR) imaging. METHODS: Forty patients had breath-hold three-dimensional fast spoiled gradient-recalled MR imaging of the abdomen done before and after i.v. administration of one of four doses of gadoterate meglumine (0.075, 0.100, 0.150, or 0.200 mmol/kg). Peak enhancement values and the time to peak enhancement of splenic parenchyma were compared (values are reported as means +/- standard deviations). RESULTS: Peak enhancement values were 154 +/- 99%, 215 +/- 109%, 276 +/- 170%, and 349 +/- 144 +/- for the doses of 0.075, 0.100, 0.150, and 0.200 mmol/kg, respectively. A high correlation was found between the dose and mean peak enhancement values (R2 = .998), which varied as a linear function of the dose. The mean times to peak enhancement obtained with the four doses were not significantly different. CONCLUSION: Using doses ranging from 0.075 to 0.200 mmol/kg, the peak enhancement of splenic parenchyma is a linear function of the dose of the gadolinium chelate administered. The time to peak splenic enhancement is not affected.

Adult↗
PubMed1996

Dynamic contrast-enhanced subtraction versus T2-weighted spin-echo MR imaging in the follow-up of colorectal neoplasm: a prospective study of 41 patients.

PURPOSE: To compare dynamic contrast-enhanced subtraction (DCES) and T2-weighted spin-echo (SE) magnetic resonance (MR) imaging in the differentiation of fibrosis from recurrence during the follow-up of treated colorectal neoplasms. MATERIALS AND METHODS: Forty-one patients with 39 malignant and 16 benign lesions confirmed by means of surgery (n = 23), biopsy (n = 24), or 12-month follow-up examination (n = 8) underwent DCES MR imaging and T2-weighted SE MR imaging. Enhancement of an abnormal pelvic structure within the first 90 seconds on DCES images or high signal intensity on T2-weighted SE images was considered indicative of malignancy. RESULTS: Sensitivity, specificity, and positive and negative predictive values were, respectively, 97%, 81%, 93%, and 100% for DCES MR imaging and 77%, 56%, 81%, and 56% for T2-weighted MR imaging. The number of correctly classified lesions was significantly higher with DCES imaging compared with T2-weighted imaging (P < or = .006). CONCLUSION: DCES imaging is more accurate than T2-weighted SE imaging for differentiating fibrosis from recurrence during the follow-up of treated colorectal neoplasms.

Colon↗