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T Waggershauser

Publications and source records attributed to T Waggershauser.

32 records · Page 2Linked to original sources
PubMed1998

Renal effects of transjugular intrahepatic portosystemic shunt in cirrhosis: comparison of patients with ascites, with refractory ascites, or without ascites.

Renal effects of the transjugular intrahepatic portosystemic shunt (TIPS) were compared in 6 patients without ascites (group 1), 11 patients with ascites responding to diuretic treatment (group 2), and 6 patients with refractory ascites (group 3). Seven days after insertion of TIPS, 24-hour urinary sodium excretion had increased in patients with ascites: 113 +/- 16 mmol to 170 +/- 30 mmol (P = .012) in group 2, and 22 +/- 8 mmol to 77 +/- 27 mmol (P = .050) in group 3. In group 3, fractional sodium excretion tended to increase from 0.26% +/- 0.14% to 0.62% +/- 18% (P = .081). The relative increase of urinary sodium excretion (to 444% +/- 122%) and fractional sodium excretion (to 413% +/- 127%) in group 3 was significantly (P < .05) higher than in group 1 and group 2, respectively. Creatinine clearance and 24-hour urinary volume were not significantly changed in either group. Patients with Child-Pugh class C had a more pronounced effect of TIPS on urinary sodium excretion (increase to 396% +/- 115% vs. 139% +/- 15%; P = .066) and on fractional sodium excretion (increase to 415% +/- 103% vs. 94% +/- 15%; P = .020) than patients with less-severe liver disease. Fractional sodium excretion of less than 0.35% before TIPS was found to be an indicator of renal response to TIPS. The effect of TIPS on urinary sodium excretion and on fractional sodium excretion was related to the patients' Child-Pugh score (r = .55; P = .007 and r = .68; P = .001, respectively) and inversely to their fractional sodium excretion (r = -.44; P = .047 and r = -.54; P = .012, respectively) before TIPS. These data demonstrate that TIPS affects renal sodium handling in patients with ascites, particularly in patients with refractory ascites. Severity of liver disease and fractional sodium excretion before TIPS are parameters to predict the extent of the renal response.

Adult↗
PubMed1998

[Contrast medium studies of the venous system].

PURPOSE: To give an overview of various diagnostic techniques and indications for phlebography in different parts of the body. METHODS: Procedures of conventional phlebography of the lower and upper extremity and cavography are described and their indications in comparison to alternative techniques are discussed. The literature is reviewed with regard to specific advantages and disadvantages of the different methods. RESULTS: Conventional phlebography with iodine contrast media is still considered to be the gold standard in many regards. The diagnosis of acute and chronic thrombotic disease, venous vascular occlusions, hemodynamic malfunctions and anatomic variants of the venous system can readily be established with contrast phlebography. DISCUSSION: Main disadvantages of contrast studies of the venous system are radiation exposure and adverse effects of contrast media. Non-invasive methods such as ultrasound and MR-phlebography are becoming more and more popular and may replace venography. Other techniques such as CT-phlebography and the use of CO2 as contrast medium are under investigation. The latter can be indicated in the case of contraindications against iodine contrast media. CONCLUSION: When choosing diagnostic methods for the venous system, their sensitivity and specificity for specific diagnoses and vascular territories have to be balanced against the risks and disadvantages.

Contrast Media↗
PubMed1998

[Vena cava filter. Indications, complications, clinical evaluation].

INTRODUCTION: Pulmonary embolism is the third leading cause of death in the western countries. If anticoagulation fails or is contra-indicated, or if the risk for pulmonary embolism is increased for other reasons, the percutaneous implantation of a vena cava filter should be considered. METHODS: The available filters can be differentiated by the design (cone, basket, net-types), by the material, and by their removability. The rate of complications (caval thrombosis, fracture of filter) and the in vitro efficacy in trapping thrombotic clots is dependent on the specific filter type. RESULTS: In clinical practice there is no evidence for significant differences in trapping efficacy among the different filters. About 4% of all patients treated by caval filters still can have pulmonary embolism, and 1% will have a fatal outcome. Dependent on the filter type, the most common complication is caval thrombosis, in up to 25% of cases. CONCLUSION: The percutaneous implantation of caval filters can readily be performed by interventional radiologists. However, randomized clinical studies failed to clearly document efficacy of caval filters. Therefore, indication has to be considered carefully.

Humans↗
PubMed1998

Transjugular intrahepatic portosystemic shunt (TIPS) for variceal bleeding in portal hypertension: comparison of emergency and elective interventions.

Nonsurgical reduction of portal hypertension by transjugular intrahepatic portosystemic shunt (TIPS) is widely used for prevention of variceal rebleeding (elective TIPS). Information is limited about the value of emergency TIPS for acute variceal bleeding unresponsive to endoscopic and drug therapy. The aim of the present study was therefore to determine whether the effects and complications differ between emergency and elective TIPS in patients with cirrhosis of the liver. TIPS was performed in 11 patients with acute variceal bleeding unresponsive to endoscopic treatment and 22 patients in stable condition after an episode of variceal bleeding. Clinical examination, blood sampling, Doppler sonography of TIPS flow, and upper gastrointestinal endoscopy were performed at days 1, 7, and 30 and at three-month intervals after TIPS. Mean follow-up was 549 (1-987) days. Bleeding was controlled by emergency TIPS in 10/11 patients. Probability of survival was not different after emergency and elective TIPS (0.73 vs 0.84 at one year). Early rebleeding (< or =2 weeks) occurred more often after emergency TIPS (3/11 vs 0/22 patients; P = 0.03), but there was no significant difference in late rebleeding. Occlusion of TIPS was more frequent after emergency TIPS. Occurrence of TIPS stenoses was identical in both groups (4/11 vs 8/22). De novo or deterioration of preexisting hepatic encephalopathy was similar (18% vs 24%; NS). It is concluded that TIPS is effective for control of acute variceal bleeding unresponsive to endoscopic and drug treatment. Early rebleeding and stent occlusion occurred more often after emergency TIPS. Late rebleeding, complications, and long-term survival did not differ from elective TIPS.

Acute Disease↗
PubMed1998

Experiences with novel techniques for reduction of stent flow in transjugular intrahepatic portosystemic shunts.

The transjugular intrahepatic portosystemic shunt (TIPS) may deteriorate liver function and can cause encephalopathy in patients with cirrhosis of the liver. Then reduction of TIPS flow may be required. We here report several attempts to reduce shunt flow in TIPS-induced encephalopathy or liver function impairment with novel techniques. Three patients with cirrhosis of the liver were investigated: Two with severe recurrent encephalopathy and one with impaired liver function following TIPS insertion. Insertion of a reducing stent was ineffective to decrease shunt flow velocity in one patient with severe coagulopathy. Sufficient reduction of shunt flow was achieved by embolizing the space around the hourglass waist of the reducing stent with an occlusion emulsion. Insertion of a conventional stent within the preexisting TIPS with or without additional embolization reduced TIPS flow in the other patients. After reduction of shunt flow encephalopathy improved and liver function returned to the level before TIPS, respectively. During follow-up no occlusion of TIPS was observed. Thus, reduction of shunt flow velocity can be achieved by insertion of an additional stent into a curve-shaped TIPS. Embolization can be helpful to decrease TIPS flow, particularly in patients with severe coagulopathy. Reduction of TIPS flow can correct TIPS-induced complications.

Blood Flow Velocity↗
PubMed1996

[Initial experiences with pulsed fluoroscopy on a multifunctional fluoroscopic unit].

PURPOSE: Comparison of radiation doses in pulsed and continuous fluoroscopy to quantify the dose reduction by pulsed fluoroscopy. Further, the applicability of pulsed fluoroscopy in clinical routine has been evaluated. MATERIALS AND METHODS: In a human pelvic phantom, the radiation dose (skin entry dose in cGycm2) was measured at two pulses per second (pps), 3 pps, 6 pps, 12 pps and continuous fluoroscopy mode, respectively, using image-intensifier entries of 38 cm, 25 cm, and 17 cm. 300 examinations were carried out, and the results of the different fluoroscopy modes were registered. RESULTS: Dose reduction depends on the image-intensifier entry. Compared to the radiation dose in continuous fluoroscopy, with 12 pps fluoroscopy the radiation dose can be reduced at a minimum of 51%, with 6 pps fluoroscopy to 40%, with 3 pps fluoroscopy to 20%, and with 2 pps fluoroscopy to a minimum of 14.5%. Clinical routine has shown that 78% of all examinations can be performed with 2 or 3 pps fluoroscopy mode. In 12.7% of the cases pulsed fluoroscopy of diverse frequencies was used, in an additional 2% combined with continuous fluoroscopy. Exclusively, continuous fluoroscopy has been employed in 2% of the cases. CONCLUSIONS: Using pulsed fluoroscopy, an 80% reduction of the radiation dose compared to continuous fluoroscopy is possible. About 96% of all examinations can be performed with pulsed fluoroscopy of different pulse rate and without using continuous fluoroscopy.

Diagnostic Tests, Routine↗
PubMed1995

[The percutaneous treatment of surgical and catheter-angiographic vascular complications].

PURPOSE: Technical innovations of angioplasty have introduced new therapeutic options in the treatment of symptomatic arteriosclerotic disease. Atherectomy devices, aspiration catheters and vascular endoprostheses can be used not only for angioplasty purpose but also for correction of iatrogenic dissections and thromboembolic complications. MATERIAL AND METHODS: 54 patients with vascular complications after surgical (n = 7) and percutaneous (n = 47) interventions were observed in a 5 years period. The complications included acute dissections in 34 cases, acute thrombosis in 4 cases, distal embolism after angioplasty in 14 cases, and two cases with arterial rupture after balloon dilatation. RESULTS: 34 patients with dissections and 18 patients with acute thrombosis were treated. Stent implantation for repair of vessel dissection was successful in 33 of 34 cases. Percutaneous catheter aspiration in combination with local thrombolysis was successful in 4 cases with local thrombosis. Distal emboli after angioplasty were successfully removed using aspiration catheters in 13 of 14 patients. Vessel rupture after angioplasty was closed with prolonged balloon dilatation in two patients avoiding emergency surgery. CONCLUSION: Using newly developed intravascular technologies such as atherectomy, stents, and catheter aspiration, many iatrogenic complications after vascular surgery or vascular interventions can be treated. These technologies should be available in every radiology department performing angioplasty.

Acute Disease↗
PubMed1995

[Reducing radiation dosage with modern DSA equipment].

PURPOSE: In angiographic and interventional procedures the often long fluoroscopy times add a great deal to the total patient dose. The new Multistar T.O.P. (Siemens) is equipped with various features for dose reduction. In this study pulsed fluoroscopy was tested versus standard continuous fluoroscopy and supervisions. MATERIALS AND METHODS: Fluoroscopy with 3, 7.5, and 15 pulses/s in the Multistar T.O.P. were compared to standard fluoroscopy and to reduced-dose supervision in a human pelvic phantom. The skin entry dose and pelvic dose were continuously registered. RESULTS: The supervision mode used 58% of the dose used in continuous fluoroscopy. Pulsed fluoroscopy with 15 pulses/s required 54%, 7.5 pulses/s 27% and 3 pulses/s. These provide adequate image quality with only 10% of the standard dose. CONCLUSIONS: It was possible to save up to 90% of the fluoroscopy dose in interventions and angiographies when using the new pulsed fluoromodes available in the Multistar T.O.P.

Angiography, Digital Subtraction↗
PubMed1991

[A 3-dimensional reconstructive procedure in lumbar computed tomography].

In this study, 50 patients were examined by a Siemens' "Somatom Plus"; continuous 2 mm sections between the third lumbar and first sacral vertebra were obtained. The accuracy of the 3-D reconstruction software programme was checked by measuring a polyethylene phantom of a second lumbar vertebra. Reconstruction was carried out with a threshold definition of 150 Hu. In each case, four standard projections and medio-sagittal, medio-lateral and coronary sections were reconstructed, photographed and compared with axial CT sections and conventional radiographs. All these imaging procedures were suitable for the diagnosis of osteochondrosis and chondrosis. Spondylosis was diagnosed more frequently on 3-D CT. Spondylarthrosis, with narrowing of the intervertebral foramina and root canals is shown particularly well by 3-D CT, since the entire extent of these structures can be seen. 3-D surface reconstruction of the lumbar spine is useful in the diagnosis of lumbar spondylarthrosis with narrowing of the root canals and of the spinal canal. This method of axial Ct is superior to conventional radiography of the lumbar spine in the usual two planes.

Adult↗
PubMedDate not supplied

Interventional radiological procedures in impaired function of surgically implanted catheter-port systems.

PURPOSE: System-related complications in surgically implanted catheter-port systems (CPS) for intraarterial (i.a.) chemotherapy are well known. In most cases of complications, the treatment must be interrupted and the catheter-port system must be repaired surgically. We describe microinvasive interventional radiological procedures to correct some dysfunctions of CPS. METHODS: Five patients with repetitive dysfunction of CPS were treated with interventional techniques. Two patients presented with perfusion impairment, one patient had a pseudoaneurysm of the hepatic artery, and two patients presented with catheter displacement. Radiological interventions included mechanical recanalization with a guidewire, vascular stenting, and correction of catheter dislocation with a goose-neck snare. RESULTS: In all cases, correct function of the CPS was restored. No intervention-related complications occurred and surgery was avoided. Chemotherapy could be continued for a period of 4--10 months. CONCLUSION: For some system-related complications, minimally invasive radiological interventions can be used to restore the function of CPS for i.a. chemotherapy.

Aged↗
PubMedDate not supplied

Hepatic arterial infusion with oxaliplatin, folinic acid, and 5-fluorouracil in patients with hepatic metastases from colorectal cancer: role of carcino-embryonic antigen in assessment of response.

BACKGROUND: Therapy for patients with hepatic metastases from colorectal cancer (CRC) remains controversial and may be improved by regional oxaliplatin which proved to be effective when administered systemically to patients with advanced CRC. METHODS: During the current study, which aims to determine the maximum tolerated dose, the dose-limiting toxicity, and the pharmacokinetics of oxaliplatin applied as hepatic intra-arterial infusion combined with folinic acid and 5-fluorouracil in patients with hepatic metastases from CRC, serial levels of carcino-embryonic antigen were determined and their relationship to response to therapy was assessed. RESULTS: Toxicity mainly consisted of nausea, pain, mucositis, sensorial neuropathy, diarrhoea, and thrombocytopenia. The results of tumor marker analyses suggest that progressive disease may be detected early by increasing CEA levels and responsive disease may be characterized by low or decreasing values. CONCLUSIONS: Further analyses are warranted to determine the role of CEA in the assessment of response as compared to imaging techniques.

Aged↗
PubMedDate not supplied

Effects of transjugular intrahepatic portosystemic shunt (TIPS) on quantitative liver function tests.

BACKGROUND/AIMS: The transjugular intrahepatic portosystemic stent-shunt (TIPS) has been established as a new effective treatment for portal hypertension in advanced liver disease. Impairment of liver function due to reduced portal venous perfusion is considered to be a major risk of TIPS, and the shunt leads to an increase in the incidence of hepatic encephalopathy (HE). Known complications, like the increase in the incidence of HE or TIPS stenosis, are diagnosed either clinically or by doppler ultrasound. It is not practicable to use quantitative liver function tests in the diagnostic work-up of HE, and medical or interventional therapy can be established after clinical diagnosis. Still, information is limited about the influence of TIPS on quantitative liver function tests in patients with liver cirrhosis. Therefore, the aim of this prospective study was to assess the effects of TIPS on various liver function tests. METHODOLOGY: Fifteen patients with liver cirrhosis, a hepatopetal portal flow before TIPS, and an uncomplicated course without stenosis after elective TIPS were analysed. Liver function was quantitatively measured using the [14C]aminopyrine breath test (ABT), considered to be independent of hepatic blood flow, the monoethylglycinexylidide test (MEGX), believed to be largely dependent on hepatic blood flow, serum bilirubin, serum albumin, and prothrombin time. Measurements were performed before, 1, 3 and 6 months after TIPS. RESULTS: TIPS decreased the portal venous pressure gradient from 31.0+/-2.0 cm (SEM) H2O to 16.9+/-1.8 cm H2O (p<0.01). One, 3 and 6 months after TIPS there was no significant deterioration of liver function as assessed by ABT, MEGX or serum bilirubin, serum albumin, and prothrombin time compared to baseline values before TIPS. ABT and MEGX were significantly correlated before TIPS (r=0.72; p<0.01) and after TIPS (r=0.76; p<0.05). CONCLUSIONS: These data show no significant deterioration of microsomal liver function as measured by the quantitative liver function tests ABT and MEGX over a period of 6 months after elective TIPS. In particular, there was no significant reduction of the MEGX-test considered to depend predominantly on hepatic blood flow. Thus, there is no need for the quantitative liver function tests ABT and MEGX in the routine management of patients following the TIPS procedure.

Adult↗