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H Wenk

Publications and source records attributed to H Wenk.

At least 37 records · Page 2Linked to original sources
PubMed1994

[PTFE prostheses in infrarenal aneurysms of the abdominal aorta].

Postoperative dilatation of Dacron vascular grafts can lead to aneurysms and rupture of the prosthesis making it necessary to change the graft by operation. Therefore, 15 patients at Lübeck University Hospital underwent replacement of the aorta with PTFE prostheses due to infrarenal aortic aneurysms. Ultrasound measurements 2-12 months postoperatively revealed a dilatation of 11.6% concerning tubular grafts, 11.5% for the shafts and 14.6% for the limbs of bifurcation grafts compared to the higher dilatation rate of Dacron prostheses described in the literature. There was no evidence of anastomotic false aneurysms, thrombosis of the limbs of bifurcation grafts, peripheral embolization or perigraft reaction. In conclusion, PTFE prostheses seem to be a means of preventing patients from having secondary complications as a result of graft dilatation. Based on our early results and the results described in the literature, PTFE prostheses can be regarded as an alternative to dacron prostheses.

Aged↗
PubMed1994

Concanavalin-A-extractable non-mucous glycoprotein concentrations in gallbladder bile of cholesterol gallstone patients.

BACKGROUND: The relationship between protein concentrations and the nucleation activity of bile in cholesterol gallstone patients has already been investigated. Nucleation promoters are mucins and concanavalin A (Con-A)-extractable glycoproteins. Nucleation inhibitors are apolipoproteins. We wanted to investigate whether a change in concentration of apolipoprotein A-I (Apo A-I) or Con-A in the bile of cholesterol stone carriers is dependent on the nucleation time. METHODS: Total protein was measured by fluorescence photometry, and Con-A-extractable glycoproteins were separated by their affinity to lectins and measured by photometry. Apolipoproteins were measured by radioactive competitive protein binding assay. RESULTS: The protein concentrations in our bile samples were 2.41 +/- 1.08 mg/ml for the whole group, 2.73 +/- 1.07 mg/ml for a nucleation time less than 3 days, and 2.04 +/- 1.00 for a longer nucleation time. The concentration of the Con-A fraction accounted for 0.289 +/- 0.096 mg/ml, 0.306 +/- 0.081 mg/ml, and 0.274 +/- 0.109, respectively. The Apo A-I concentration was 52 +/- 64 micrograms/ml; 50 +/- 56 micrograms/ml for a nucleation time less than 3 days and 85 +/- 133 micrograms/ml for a longer nucleation time. CONCLUSIONS: Obviously, individual protein fractions have an effect on the nucleation behaviour of gallbladder bile in cholesterol gallstone patients.

Apolipoprotein A-I↗
PubMed1992

[The chemical composition of gallstones and their suitability for litholysis and lithotripsy].

The chemical composition of gallstones removed at surgery from 107 patients (81 women, 26 men; mean age 59 [18-85] years) was examined. In 64 women (79%) and 21 men (81%) microchemical analysis demonstrated concrements with a more than 50% cholesterol content (500 mg/g). Using as definition of cholesterol stones a 75% cholesterol content, only 35 women (43%) and 10 men (39%) would be classified as cholesterol stone carriers. Grossly visible layer formation was present in 18 stones; in eight stones calcium content was higher in the outer layer than in the core. There was no demonstrable relationship between gallstone composition and age.

Adolescent↗
PubMed1992

[Laparoscopic laser cholecystectomy].

In an ex vivo- and an animal study a Holmium-YAG laser, a Nd:YAG laser and a CO2 laser were examined. For laparoscopic cholecystectomy the pulsed Holmium:YAG laser proved to be the best instrument. Dissecting and haemostatic effects were connected when working with a power of 4 watts. Dissected area per minute was 112 mm2, gallbladder dissection (15 cm2) can be performed in 13 min. In the animal study the cholecystectomy lasted 30 min on average when the Holmium:YAG laser was used. Bleeding was not observed, development of smoke was tolerable.

Cholecystectomy, Laparoscopic↗
PubMed1992

[Lowering peripheral vascular resistance by distal arteriovenous fistula surgery. Clinical and experimental studies].

Vascular run off has an important influence on patency rates of infrapopliteal bypasses especially when prosthetic grafts are used. Construction of a distal arteriovenous fistula can improve volume and velocity of graft flow. 39 patients, 14 of them diabetic, had femoro-crural PTFE-bypasses. A distal arteriovenous fistula in common ostium technique was established in 20 cases. The patency rate (early occlusions) was improved, especially diabetic patients seemed to profit by lowering the peripheral outflow resistance, which was measured intraoperatively. The influence of arteriovenous fistulas of different calibre on bypass flow and perfusion was analysed in a circulation model.

Arteriovenous Shunt, Surgical↗
PubMed1991

Diagnostic fine-needle puncture of the gallbladder with US guidance.

From February 1988 to January 1990, 118 fine-needle diagnostic punctures of the gallbladder (DPG) were performed under continuous ultrasound (US) guidance on symptomatic patients with gallstones. The first attempt at gallbladder puncture and aspiration was successful in every patient with use of a 22-gauge needle and continuous US visualization of the needle tip. The aspirated volume varied between 3 and 88 mL (average +/- standard deviation, 25.0 mL +/- 15.3). Biliary analysis revealed an elevation of the cholesterol saturation index in patients with cholesterol gallstones (attenuation at computed tomographic examination of 50 HU or less) relative to that in patients with pigment stones (attenuation more than 50 HU) (1.3 +/- 0.2 vs 1.0 +/- 0.1, P less than .05). The nucleation time was prolonged in patients with pigment stones (19.3 days +/- 3.5 vs 1.8 days +/- 0.8 for patients with cholesterol stones, P less than .001). All patients remained hospitalized for 24 hours after DPG and were reexamined on an outpatient basis at 1 and 3 months thereafter. No complications were detected during either short-term observation or long-term follow-up. The authors conclude that DPG is a safe and valuable technique in the diagnostic work-up of gallstone patients to establish their suitability for nonoperative treatment.

Adolescent↗
PubMed1991

Total biliary protein, mucus glycoproteins, cyclic-AMP, and apolipoproteins in the gallbladder bile of patients with cholesterol stones and stone-free controls.

The concentrations of total protein, mucus glycoprotein, cyclic-AMP, and apolipoproteins A-I, A-II, and B were determined in the gallbladder bile of patients with cholesterol gallbladder stones and in stone-free controls. The total protein content was significantly increased in gallstone patients (2.03 +/- 0.6 versus 1.31 +/- 0.67 mg/ml; p less than 0.05), as was the mucus glycoprotein concentration (380 +/- 88.5 versus 128 +/- 57.2 micrograms/ml; p less than 0.05). The cyclic-AMP concentration in the gallbladder fluid was increased up to 91 +/- 20 pmol/100 microliters in the gallstone subjects, as compared with 46 +/- 26 pmol/100 microliters (p less than 0.01) in stone-free controls. Cyclic-AMP concentrations correlated positively with the glycoprotein content of the bile in cholesterol gallstone patients (r = 0.66; p less than 0.05). The apolipoprotein concentrations were determined by the radial immundiffusion technique. The corresponding values for patients with stones and controls were 7.5 +/- 0.8 versus 3.0 +/- 0.8 for Apo A-I (p less than 0.025), 10.4 +/- 0.6 versus 6.3 +/- 1.3 for Apo A-II (p less than 0.02), and 1.9 +/- 0.5 versus 1.6 +/- 0.2 mg/dl for Apo B (NS), respectively. Biliary proteins probably play an important role in the nucleation process during the pathogenesis of cholesterol gallbladder stones.

Adult↗
PubMed1990

Fistuloscopy--an adjuvant technique for sealing gastrointestinal fistulae.

Endoscopic occlusion of gastrointestinal fistulae can be successfully achieved in a high percentage of patients. In cases where the intestinal opening of the fistula is not accessible, such treatment was hitherto impracticable. Fistuloscopy is a new technique which we have devised, using a flexible endoscope advanced percutaneously along the fistula tract to seal these gastrointestinal fistulae. Eleven out of 17 enterocutaneous fistulae and 5 out of 8 abscesses could be sealed using this technique. The complications in this series were all caused by fibrin glue injection into the fistulae under pressure. One patient died of an air embolism. Provided that elevation of the air pressure in the fistula system is strictly avoided, fistuloscopy is a safe and potent method of occluding gastrointestinal fistulae, which otherwise need prolonged conservative treatment or hazardous surgical intervention.

Aged↗
PubMed1990

[Preventing the recurrence of common bile duct calculi following endoscopic papillotomy with ursodeoxycholic acid].

The effect of ursodeoxycholic acid on recurrence prevention of choledochal calculi after endoscopic sphincterotomy (EPT) was evaluated in 46 patients, whose bile duct stones had been removed endoscopically. 22 patients received 500 mg of ursodeoxycholic acid once a day, 24 patients received placebo. 1 recurrent stone could be detected in the ursodeoxycholic acid treated group 19 months after EPT, whereas 4 recurrent stones occurred in the placebo group about 16 months after EPT. Cholesterol saturation index decreased significantly by the ursodeoxycholic acid treatment 12 and 24 months after EPT (0.93 +/- 0.17 vs. 0.69 +/- 0.12 vs. 0.72 +/- 0.07). The nucleation time increased statistically significant from 9.0 days to 20.4 (12 months) and 17.7 (24 months) days, respectively. Obviously, pharmacological effects of ursodeoxycholic acid exist which modify important processes in the gallstone's pathogenesis.

Aged↗
PubMed1989

Laser vaporization of leiomyoma of the esophagus.

We present the case of a 67-year-old man with a stenosing leiomyoma of the esophagus, which led to dysphagia. Because of severe concomitant diseases, thoracotomy was not possible in this patient. Endoscopic laser ablation was a fast and successful treatment; more than 2 years have passed without any sign of recurrence.

Aged↗
PubMed1989

[Percutaneous transhepatic laser lithotripsy of gallstones--results of animal experiments].

Since laserinduced shock wave lithotripsy of gallstones is possible for treatment of common bile duct stones, the percutaneous transhepatic laserlithotripsy of stones in the gallbladder is examined in an animal study. In 8 animal experiments it could be shown that puncture of the gallbladder, dilatation of the working channel, (laserinduced) shock wave lithotripsy, removal of the fragments and the instruments are possible in one session. Neither when performing simple closure of the wound by suture nor by fibrinsealing severe side-effects could be recognized. After laserlithotripsy ablation of epithelium and hematomas can be observed, which are restituted within one month. The experiments show that in organ-saving shockwave lithotripsy there is no need for waiting for the development of a fistula and the percutaneous approach can be simplified.

Animals↗
PubMed1989

Percutaneous transhepatic cholecysto-lithotripsy (PTCL).

Percutaneous transhepatic cholecystolithotripsy (PTCL) by laser or ultrasound is a minimally invasive form of treatment for gallstones. All the steps of the procedure can be performed in a single session. In clinical use severe side effects have not been observed.

Cholelithiasis↗
PubMed1989

[Intramural pseudodiverticulosis of the esophagus].

A rare case of oesophageal intramural pseudodiverticulosis is described. The typical radiological appearance in the oesophagogram is demonstrated and correlated with the histopathology. Review of the literature leads to the hypothesis that oesophageal pseudodiverticulosis may be the identical result of different diseases.

Aged↗