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W Cwikiel

Publications and source records attributed to W Cwikiel.

45 records · Page 3Linked to original sources
PubMedDate not supplied

Deposition of platelets and neutrophils in porcine iliac arteries after angioplasty and Wallstent placement compared with angioplasty alone.

PURPOSE: This study was designed to compare deposition of 111In-labeled platelets and neutrophils after balloon angioplasty (PTA) alone and PTA plus Wallstents. METHODS: Histological investigation was performed with scanning electron microscopy (SEM). Fifty percent stenoses of both iliac arteries was created by resorbable ligature in 13 pigs. After 30 days, PTA was performed bilaterally with an additional stenting procedure done on one side. Autologous platelets were labeled and reinfused before the interventional procedure in six pigs, and labeled neutrophils were used in seven pigs. The deposition of the labeled cells was recorded in vivo over 270 min using a scintillation camera. The results were correlated with in vitro measurements. RESULTS: Scanning revealed significant increase in platelet and neutrophil deposition at the site of the stent compared with the site where PTA alone was undertaken. In vitro measurements confirmed these differences. SEM demonstrated a fibrin lining on the stent surface and numerous adherent platelets. The adjacent arterial lumen was almost completely covered by fibrinous material. The PTA-alone site demonstrated denudation of endothelial cells and less fibrinous material, as well as platelets and leukocytes. CONCLUSION: The complex interaction in the response of the vessel wall and flowing blood involves both platelet and neutrophil adhesion. The self-expandable vascular endoprosthesis contributes to increased deposition of platelets and neutrophils as seen in this experimental model of nonatheromatous stenosis.

Angioplasty, Balloon↗
PubMedDate not supplied

Isolated liver perfusion using percutaneous methods: an experimental study in the pig.

PURPOSE: To develop a method for isolated perfusion of the liver using radiological methods. METHODS: Twenty-one pigs, weighing about 20 kg, were divided into three groups. By transjugular and transfemoral approaches two occlusion balloons were placed in the inferior vena cava cranial and caudal, respectively, to the origin of the hepatic veins. One occlusion balloon was placed transfemorally in the common hepatic artery. Another occlusion balloon was inserted in the main branch of the portal vein via the transjugular-transhepatic approach in 11 pigs (groups 1 and 2), and in 10 pigs (group 3) by a percutaneous transhepatic route. After inflation of the balloons, patency of the isolated liver circulation was evaluated by recirculation of 99Tcm-labelled human albumin during 30 min. Blood tests were obtained after 1, 3, 5, 10, 15, and 30 min to evaluate leakage from the liver to the systemic circulation. RESULTS: Increasing leakage to the systemic circulation from the isolated liver circulation was observed in groups 1 and 2. In the third group the leakage was less than 10%. CONCLUSION: In an experimental animal model, isolated perfusion of the liver with minor leakage to the systemic circulation may be achieved using radiological methods.

Animals↗
PubMedDate not supplied

Double-balloon catheter for isolated liver perfusion: an experimental study.

PURPOSE: Further development of a previously described interventional method for isolated liver perfusion (ILP) with a new double-lumen balloon catheter, and evaluation of the side-effects of such isolation. METHODS: In six pigs a double-balloon occlusion catheter was placed via the transjugular approach with its tip in the portal vein. One of the balloons was positioned in the inferior vena cava (IVC), cranial to the origin of the hepatic veins and the other balloon in the portal vein. By the transfemoral approach, a single-balloon occlusion catheter was placed in the IVC caudal to the origin of the hepatic veins. A third catheter was placed by the transfemoral route with the occlusion balloon in the proper hepatic artery. After inflation of all balloons 99Tc(m)-labelled human serum albumin was recirculated through the liver. The isolation was evaluated by repeated measurement of radioactivity levels in peripheral blood. Laboratory tests of liver and pancreas function, and hemoglobin, were taken before, at the end of, and 3 days after the procedure. Blood gases were tested at the beginning and end of the procedure. RESULTS: One pig died during the procedure due to technical failure and was excluded from the study. In the other pigs leakage from the isolated liver to the systemic circulation increased slowly, up to 9.7% (mean) during 30 min of recirculation of the perfusate through the liver. Laboratory tests were normal in all pigs except insignificant acidosis directly after the procedure and the slight elevation of s-ALAT after 3 days. CONCLUSIONS: Only minor leakage from the liver to the systemic circulation was noted during ILP performed with a new, double-balloon catheter. There were no serious side effects.

Animals↗
PubMedDate not supplied

Stent recanalization of chronic portal vein occlusion in a child.

An 8-year-old boy with a 21/2 year history of portal hypertension and repeated bleedings from esophageal varices, was referred for treatment. The 3.5-cm-long occlusion of the portal vein was passed and the channel created was stabilized with a balloon-expandable stent; a portosystemic stent-shunt was also created. The portosystemic shunt closed spontaneously within 1 month, while the recanalized segment of the portal vein remained open. The pressure gradient between the intrahepatic and extrahepatic portal vein branches dropped from 17 mmHg to 0 mmHg. The pressure in the portal vein dropped from 30 mmHg to 17 mmHg and the bleedings stopped. The next dilation of the stent was performed 12 months later due to an increased pressure gradient; the gastroesophageal varices disappeared completely. Further dilation of the stent was planned after 2, 4, and 6 years.

Catheterization↗
PubMedDate not supplied

Treatment of adenocarcinoma of the liver with mitomycin, hyaluronidase, and ethanol: an experimental study in the rat.

PURPOSE: To evaluate the effect of intratumorally injected ethanol, mitomycin, mitomycin with hyaluronidase, and hyaluronidase on tumor growth in an experimental model. METHODS: A suspension of 1 x 10(6) cells of chemically induced adenocarcinoma was implanted into the liver of 52 rats. Seven days later the rats were divided into groups according to treatment and injected via a midline laparotomy with ethanol, mitomycin, mitomycin with hyaluronidase, or hyaluronidase. A control group was treated with saline. The rats were killed 7 days after treatment. The tumor growth ratio was calculated, and the results compared for the different groups. Wilcoxon's rank sum test was used for statistical evaluation. RESULTS: The tumor growth ratio was significantly reduced after injection of mitomycin (p < 0.01) but not after ethanol. Hyaluronidase alone did not reduce the tumor growth ratio and had no synergetic effect with mitomycin. CONCLUSION: In an animal model intratumoral treatment of adenocarcinoma of the liver with mitomycin was significantly more efficient than similar treatment with saline or ethanol.

Adenocarcinoma↗
PubMedDate not supplied

Metallic stents in malignant biliary obstruction: results of a multicenter European study of 240 patients.

PURPOSE: In this retrospective multicenter study, the authors analyzed the clinical efficacy of different metallic stents in the palliative treatment of patients with neoplastic obstructive jaundice. PATIENTS AND METHODS: Two hundred forty patients were treated in four European centers. Causes of obstruction were pancreatic carcinoma (n = 84), biliary neoplasm (n = 99), metastases in hilar nodes (n = 34), primary or secondary liver tumors (n = 4), and other tumors (n = 19). A total of 388 metallic stents were used: 300 Wallstents, 35 nitinol Strecker stents, 40 Gianturco-Rosch Z stents, and 13 tantalum Strecker stents. RESULTS: Overall 25- and 50-week survival rates were 42% and 16%, respectively; the 30-day mortality rate was 14.6%. Two deaths were related to the procedure (0.8%); 19 patients (8%) had major complications. The 25-week patency rate was significantly higher for the nitinol Strecker stents and the Wallstents (78% and 67%, respectively) than for the Z stents and the tantalum Strecker stents (30% and 20%, respectively) (P < .01 and P < .001, respectively). Average patency was 8.3, 5.9, 2.3, and 4.0 months, respectively. Reintervention due to stent obstruction was necessary in 53 patients. CONCLUSION: The Wallstent and the nitinol Strecker stents were the most effective in achieving long-term palliation. Patency was significantly affected by the level of obstruction but not by the type of obstructing tumor.

Aged↗
PubMedDate not supplied

Radionuclide angiography in the evaluation of iliofemoral venous patency.

Radionuclide angiography (RNA), was compared to contrast phlebography (CP) for evaluation of iliofemoral venous patency. Twenty-three patients that six months earlier had been treated for iliofemoral venous thrombosis were investigated. The reproducibility of RNA was good as the interindividual and intraindividual variation was 80-85% and 90-95% respectively. The sensitivity of RNA was 91% in the iliac and 65% in the femoral segment. The specificity was 78% in the iliac and 74% in the femoral segment. The advantages as compared to CP are: easy performance, easy to repeat, no adverse reactions and visualization of the whole venous system. The disadvantages are: e.g. difficulties in interpretation in bilateral disease or abnormal anatomy. RNA is recommended as a screening method for suspected iliac venous obstruction and for follow-up of venous patency after iliofemoral venous thrombosis.

Adolescent↗