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G W Kauffmann

Publications and source records attributed to G W Kauffmann.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Radiologic diagnosis of bone metastases].

Metastases are the most common malignant tumors of the skeleton. Several imaging modalities can be engaged for the diagnosis of skeletal metastases. They may be combined, depending on the individual clinical setting. Plain films are used for evaluation of symptomatic regions of the skeleton. Sensitivity is low, but benign skeletal disorders causing clinical symptoms can usually be identified in plain films. Bone scintigraphy is employed for a survey of the entire skeleton with high sensitivity for the presence of metastases, but only poor specificity. Computed tomography (CT) and magnetic resonance imaging (MRI) are advanced diagnostic methods, essential particularly in the diagnosis of metastatic spinal disease. Using CT, additional percutaneous bone biopsies can be performed easily and safely. Of all imaging modalities, MRI has the highest sensitivity for skeletal metastases. Other advantages are the possibility of multidirectional slice positioning and excellent soft tissue contrast.

Bone Neoplasms↗
PubMed1998

[Hydro-CT in detection and staging of pancreatic carcinoma].

PURPOSE: To document our experience with spiral hydro-CT of the pancreas based on a combination of pharmacologic intestinal paralysis and water distension of the stomach and duodenum with specific reference to tumor detection rate, differentiation of malignant versus benign tumors and assessment of tumor resectability in a prospective study on 211 consecutive patients. MATERIAL AND METHODS: Between May 1994 und September 1997, 211 patients with suspect of pancreatic neoplasm from clinical, laboratory or other imaging data were examined. Our Hydro-CT techniques were based on intravenous injection of 40 mg N-butylscopolaminiumbromid (Buscopan) for intestinal paralysis, gastric and duodenal wall distension by oral administration of an average of 1.5 l warm tap water, 30 degrees RAO patient's positioning, individualized contrast injection technique using portal vein enhancement as reference and thin slice spiral CT (3 mm slice thickness, 6 mm table feed and 3 mm secondary reconstruction). Examined parameters were: (1) tumor detection rate, (2) differentiation of malignant versus benign disease, (3) differential diagnosis and (4) accuracy of assessment of resectability by identification of infiltration into adjacent organs and vessel structures relevant for resectability such as splenic, superior mesenteric, portal vein and celiac trunk, superior mesenteric, splenic and hepatic arteries. As gold standard for positive tumor detection and description surgery (of potentially resectable tumors) and microscopic diagnosis (of clearly unresectable tumors) were used and for negative tumor detection an event-free survival of six months, respectively. RESULTS: 96% of the examinations were well tolerated. In only 4% was on-site administration of a gastric tube required because of vomiting. In 2% of the patients a slight allergic reaction to the contrast medium was seen. The prevalence of a pancreatic neoplasm was 37.8%. In tumor detection Hydro-CT reached an overall accuracy of 94.8% with a sensitivity of 93.7% and a specificity of 95.2%. 52 patients underwent surgical exploration 34 of whom with tumorfree resection margins (RO resection) corresponding to a resection of 42.5%. In those assessment of resectability reached an overall accuracy of 94.6% with a sensitivity of 91.2% and specificity of 95.6%. CONCLUSION: The new technique of Hydro-CT based on the slice and spiral methodology including pharmacologic intestinal paralysis and water distension results in a high tumor detection rate and reliable assessment of resectability.

Aged↗
PubMed1998

[Diagnosis of pulmonary diseases with transthoracic ultrasound].

The indications or ultrasound in the evaluation of pulmonary disorders are described. Clinical applications are several lung diseases in adults and especially in children. In specific, well-defined applications, the feasibilities of ultrasound are promising. Sonography provides important additional information to chest X-ray and is even superior to CT under special circumstances. Pulmonary sonography is a useful link between conventional X-ray and more expensive cross-sectional imaging. In the evaluation of pulmonary diseases at present the potential of ultrasound is not optimally used.

Adult↗
PubMed1998

[After-care of TIPSS patients. Comparison between color Doppler ultrasound and portography].

PURPOSE: Comparison of color Doppler sonography and venous portography in patients with a transjugular intrahepatic portosystemic stent shunt (TIPSS). MATERIALS AND METHODS: In a prospective study 40 consecutive patients with TIPSS underwent venous portography and color Doppler sonography on the same day as follow-up. Shunt velocities were recorded within the TIPSS at the proximal (hepatic vein segment) and distal part (portal vein segment). RESULTS: In 28 patients with functioning TIPSS the mean shunt velocity ranged between 30 and 120 cm/s (median 60 cm/s) at the portal vein segment and between 60 and 155 cm/s (median 82 cm/s) at the hepatic vein segment. There was a significant increase of the mean shunt velocity in the hepatic vein segment (P < 0.001). In 12 patients with compromised TIPSS the mean shunt velocity was reduced to 26 +/- 7 cm/s at the portal venous end (P < 0.0001). CONCLUSION: Because of an accelerated shunt velocity in the hepatic vein segment a site-specific evaluation of both TIPSS endings is necessary with color Doppler sonography. In compromised TIPSS the shunt velocity is reduced at the portal venous end. Color Doppler sonography is a valid non-invasive means for follow-up of patients with TIPSS.

Adult↗
PubMed1998

[Use of the ultrasound contrast medium levovist in after-care of liver transplant patients. Improved vascular imaging in color Doppler ultrasound].

INTRODUCTION: A study was carried out to determine whether an improvement in the detection of vascular signals in patients after orthotopic liver transplantation can be achieved by the use of ultrasound contrast medium in colour Doppler sonography. MATERIAL AND METHODS: In the early postoperative follow-up of liver transplant recipients, 31 colour Doppler sonograms were obtained in 21 patients before and after intravenous injection of the ultrasound contrast agent Levovist (Schering, Berlin). A grading score with four categories was used to evaluate the sonograms with special regard to the visibility of colour and flow signals in the hepatic artery and also in the portal vein and the hepatic veins. The arterial and portal venous signals were evaluated in the hepatic portal and in the left and right lobe. RESULTS: With contrast enhancement significantly better arterial signals were seen in 20 of 31 sonograms for the hepatic portal, in 22 for the right lobe and in 26 for the left lobe. Better portal vein signals were obtained in 17 of 31 examinations for the right lobe and in 16 for the left lobe; only little improvement was obtained for the main stem of the portal vein. For the hepatic veins there was no significant improvement. CONCLUSIONS: Early vascular complications after liver transplantation usually occur in the hepatic arteries. With the use of contrast-enhanced colour Doppler sonography, better detection of arterial and peripheral portal signals can be achieved; peripheral portal vein branches can be helpful in finding small arteries.

Adult↗
PubMed1998

[Diagnostic imaging for therapy control of primary bone tumors].

Adjuvant chemotherapy has significantly improved the prognosis of patients with bone sarcomas. Preoperative diagnostic imaging of tumor response to such therapy has become a mainstay for the assessment of prognosis, planning of surgery and further treatment. During therapy, responding tumors show characteristic changes on conventional radiography, angiography, sonography, radionuclide studies, CT and MR. The usefulness and the limitations of each imaging modality in assessing response to therapy are reviewed. The diagnostic importance of specific changes such as tumor volume reduction, calcification and tumor vascularization is discussed.

Adolescent↗
PubMed1998

[CT-angiography as a non-invasive method for the evaluation of the patency of TIPSS (transjugular intrahepatic portasystemic shunt)].

PURPOSE: To evaluate the feasibility of determining patency of the transjugular intrahepatic portosystemic shunt (TIPSS) by non-invasive CT angiography (CTA). MATERIALS AND METHODS: (1) Non-enhanced scanning of the shunt. (2) Bolus tracking by injecting 20 ml of non-ionic contrast material through a cubital vein access to determine the time to maximal shunt enhancement. (3) Contrast-enhanced spiral CT study applying a delay according to the time to peak of the shunt, 3 mm collimation, 5 mm table feed and 3 mm reconstruction interval. (4) 3D and multiplanar reconstructions. (5) Evaluation of the questions: intrahepatic shunt patent or not; evidence of intimal hyperplasia; evidence of stenosis and potential location. (6) Transjugular portography via the stent. (7) Comparison of angiographic findings and CT morphology. RESULTS: Eight patients had inconspicuous CTA. Four of them had a normal shunt at angiography, four had slight intimal hyperplasia. No intervention was necessary in these patients. CTA of three patients showed intimal hyperplasia (lumen reduction between 10% and 50%). The diagnosis was angiographically confirmed in all cases. Due to a high portosystemic gradient intervention was required in all. In five patients CTA and angiography showed a stenosis (reduction of shunt lumen > 50%). All required a revision including stent placement or PTA of the shunt tract. Four shunts were occluded; all occlusions were shown both in CTA and angiography. CONCLUSIONS: None of the shunts with normal findings at CTA required revision. All shunts conspicuous on CTA resulted in revision. In this study, CTA turned out to be an accurate, non-invasive method to evaluate the patency of TIPSS.

Angiography↗
PubMed1998

[Interventional therapy of primary and secondary tumors of the spine].

Therapeutic interventions in the skeletal system are an essential part of interventional radiology. Although in terms of figures these procedures are applied less frequently, they are very effective. Percutaneous transarterial embolization of a spinal tumor is well-established interventional treatment. It is primary treatment for preoperative devascularization, but also for palliation of pain and for reduction of tumor volume. As an alternative access for embolization, direct percutaneous puncture of a vertebra is used. A new and promising technique is vertebroplasty, the percutaneous injection of acrylic surgical cement in destroyed vertebrae. The present paper discusses indications, technique, results and complications of these interventional therapeutic modalities in the treatment of primary and secondary spinal tumors.

Bone Transplantation↗
PubMed1998

[Morphology and staging of primary mucosa-associated gastric lymphoma in hydro-CT imaging].

PURPOSE: Evaluation by hydro-CT in diagnosing and staging of primary non-Hodgkin lymphoma of the stomach (MALT). MATERIAL AND METHODS: 15 patients with MALT lymphoma underwent imaging by hydro-CT (helical CT scanning optimised for parenchymal and vessel contrast with distension of the gastric wall by water). The CT scans were evaluated for the site, morphology, extent and contrast enhancement of gastric lymphoma; in addition, the number and location of abdominal lymph nodes were examined. The results of CT imaging were compared with the findings at endoscopy + biopsy and endosonography and in case of gastrectomy also with the histopathological results. RESULTS: All lymphomas were correctly diagnosed and were mostly located in the distal parts of the stomach. MALT lymphoma typically grew submucosally, infiltration of the mucosa was rare. Most tumours showed marked contrast enhancement of the mucosa and poor enhancement of the submucosa. Hydro-CT and endosonography had similar accuracies in respect of staging of compartment I and II lymph nodes. Staging of distant nodal groups was more accurate by hydro-CT. CONCLUSION: Hydro-CT is non-invasive and may be used for diagnosis and staging of primary gastric lymphoma with a typical morphology of gastric lymphoma. Hydro-CT may be regarded as complementary to endosonography and is well suited for the initial diagnosis of gastric lymphoma as well as for the diagnosis of recurrent tumour.

Adult↗
PubMed1998

[TIPSS: 10 years of clinical experience].

UNLABELLED: To demonstrate and document 10 years of clinical experience gathered by us with TIPSS and to discuss achievements, problems and outlook. MATERIAL AND METHODS: The analysis is based on the following parameters: portosystemic gradient; morphological delineation of the portal circulation; determination of the portal perfusion fraction (PPF) and the total liver perfusion (GLP); arterial flow changes; hepatic encephalopathy; incidence of restenotic shunt occlusion and recurrent variceal bleeding. RESULTS: Variceal filling was widely reduced by TIPSS, and significantly reduced portal liver perfusion as assessed morphologically and rheologically. However, there was an immediate onset of compensated liver perfusion by increased arterial inflow. Total liver perfusion did not change significantly. In TIPSS portal decompression was readily achieved, the portosystemic gradient dropping from an average of 24 mm Hg to 10.5 mm Hg. In our series we could not demonstrate an increased incidence of hepatic encephalopathy during the 30-day post-TIPSS period. Early mortality was 4% and early rebleeding rate 3%. The 12-month re-intervention rate based on an invasive portography follow-up protocol was 76%, and the 24-month re-intervention rate was 90%. The definite occlusion rate was below 5%. Beyond a follow-up time span of 24-months the necessity for re-intervention dropped significantly: less than one-third of our patients required some sort of re-intervention. CONCLUSION: The concept of TIPSS represents an individually calibrated H-shunt. The significant reduction of post-TIPSS portal perfusion appears to be compensated by increased arterial inflow. This is reflected by an invasive flow measurement results and by the clinical results. Lethality of TIPSS is low mostly as a result of a refined technique, careful patient selection, follow-up care and meticulous shunt surveillance.

Hepatic Encephalopathy↗
PubMed1998

[The staging of renal-cell carcinomas in MRT and CT--a prospective histologically controlled study].

PURPOSE: To evaluate the accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in staging renal carcinoma. MATERIAL AND METHODS: 33 renal carcinomas were preoperatively examined for tumour staging by CT and MR imaging and correlated with histopathological staging. CT imaging was performed at first as a non-contrast scan. Finally incremental images (10 mm) after intravenous contrast injection were obtained. In MR imaging we performed a transversal T1-weighted GE sequence (112/5) with and without GDTPA, a transversal fat-suppressed double-echo sequence (3900/22/90), a coronal T1-weighted GE sequence with and without GDTPA and a coronal T2-weighted TSE sequence (2800/128). In addition, dynamic T1-weighted GE imaging after GDTPA injection as well as TOF angiography in coronal direction were performed. Finally CT and MRI findings were correlated with surgical and histopathological staging results. RESULTS: CT and MRI staging was correct in 27 and 28 of 33 tumours. Sensitivity and specificity for tumour stage T3b to T4 was for MRI and CT 88.9% and 95.8%. With MRI 4 out of 7 thrombi were correctly diagnosed with high accuracy, but via CT none. CONCLUSION: In early stage renal carcinoma CT and MR imaging yielded similar staging accuracies. In advanced renal carcinoma MRI was superior to CT imaging, especially in diagnosing tumour thrombus. Consequently the extent of tumour thrombus may be assessed by MRI which may therefore replace conventional cavography.

Adult↗
PubMed1998

Pseudolesions at T1-weighted gradient-echo imaging after administration of superparamagnetic iron oxide: comparison with portal perfusion abnormalities at CT during arterial portography.

PURPOSE: To compare specific findings at T1-weighted gradient-echo (GRE) magnetic resonance (MR) imaging performed after administration of superparamagnetic iron oxide (SPIO) with nontumorous regional portal perfusion abnormalities seen at computed tomography (CT) during arterial portography (CTAP). MATERIALS AND METHODS: The results of CTAP, MR imaging, and surgery were compared in 19 patients with liver metastases and five with benign liver tumors. MR imaging was performed by using turbo spin-echo (SE) sequences and a GRE sequence before and after infusion of SPIO. RESULTS: At CTAP, 34 nontumorous portal perfusion defects ("straight line sign," pseudolesions) were seen. After intravenous administration of SPIO, 18 nontumorous signal intensity differences were seen on T1-weighted GRE images in corresponding locations. No corresponding nontumorous signal intensity differences were seen on unenhanced MR images. The mean signal-to-noise ratio on the SPIO-enhanced GRE images was reduced from 26.3 to 16.6 in the areas of nontumorous signal intensity differences, whereas that in areas of normal portal perfusion (normal CTAP findings) was reduced to 10.2. CONCLUSION: Impaired portal perfusion decreased the uptake of SPIO in histopathologically normal regions of liver parenchyma. Resultant differences in signal intensity were better visualized on GRE than on turbo SE images.

Adolescent↗
PubMed1997

[Malignant lymphoma. Diagnosis and after-care in adults with special reference to cross-sectional imaging].

Radiological staging continues to remain the basis of a critical therapy of malignant lymphoma. As staging system, the Ann Arbor classification with some added modification is used. Up to now, CT is the imaging study of choice for staging and follow-up of cases of lymphoma. In future however, due to the advantages of the MRI, parts of the staging will be performed by MRI only. Imaging studies provide accurate measurement of extent of nodal disease. The detection of extra-nodal disease depends on the growth pattern and on the location. Focal lesions of sufficient size can be readily detected, diffuse infiltration is often missed. Computed tomography precisely reflects pathologic changes of lung involvement, but the findings are not specific. One weakness of the imaging studies is the low detection rate of splenic and hepatic involvement. Staging of gastrointestinal lymphoma has been improved by "hydro-CT" or "Hydro-MRI".

Adult↗
PubMed1997

[Lymphoma in childhood].

Manifestation of childhood Hodgkin's disease and Non-Hodgkin's lymphoma differ, especially in the latter, from those in adults. Extranodal involvement is seen even more frequently in childhood Non-Hodgkin's lymphomas than in adults. This article reviews the radiological findings in malignant lymphomas in children, explains the differences in the manifestation of Hodgkin's lymphomas, of different subtypes and of the malignant lymphomas in adults. The problems in diagnosis of organ manifestation and special problems of diagnostic imaging procedures in children are discussed.

Adolescent↗
PubMed1997

[Malignant lymphoma in childhood. Ultrasound diagnosis].

The sonographic diagnosis of malignant lymphoma in childhood is described. Malignant lymphomas are sonographically relatively uniform: initial enlargement of the lymph nodes and organs involved and disturbance of normal echo texture by mainly hypoechoic lesions can be found. Generally, four sonographic patterns of infiltration are described: diffuse, small nodular, large nodular and bulky type. Secondary, tumor-related or inflammatory complications (e.g. dislocation or compression of vessels, thoracic inlet syndrome, venous thrombosis, ileus, urinary retention, abscess and effusion) can be sonographically evaluated. Response to therapy correlates with normalization of size and echo texture and recovery from tumor-related complications. Differential diagnosis with ultrasound is based on the topographic distribution and echo pattern of infiltration and, with certain restrictions, on the echogenicity of lesions and perfusion feasible with Doppler sonography. The primary diagnosis has to be established histologically.

Child↗