PubMed Health⌕ Search

Biomedical subjects

W Kratzer

Publications and source records attributed to W Kratzer.

At least 55 records · Page 3Linked to original sources
PubMed1994

Does adequate patient selection reduce the risk of gallstone recurrence after successful extracorporeal shockwave lithotripsy?

To determine the risk of gallbladder stone recurrence in these patients, 58 of the first consecutive 61 patients with solitary stones achieving complete stone clearance after ESWL and adjuvant bile acid therapy were included in a prospective study. All patients were observed for at least 12 months following discontinuation of oral bile acids. Twenty-one patients fulfilled our postulated ideal criteria (solitary radiolucent stones between 10-20 mm initial diameter, initial stone density < 50 HU, gallbladder ejection fraction > 70%). The remaining patients (n = 37) fulfilled the criteria of the Munich study group. In patients fulfilling our ideal criteria, stone recurrence was not observed in any patient, while in those fulfilling solely the criteria of the Munich group, five instances of stone recurrence were observed (13.5% [n = 37], p < 0.1). Initial stone count is only one factor influencing the probability of gallstone recurrence following ESWL and discontinuation of oral bile acids. Our data suggest that factors such as low initial stone density at gallbladder CT and good gallbladder function not only accelerate initial stone clearance but also reduce the risk of stone recurrence after ESWL once oral bile acids have been discontinued.

Adult↗
PubMed1993

Transhepatic topical dissolution of gallbladder stones with MTBE and EDTA. Results, side effects, and correlation with CT imaging.

Forty-two patients with symptomatic gallstones (28 women, 14 men, mean age 49.8 +/- 13.2 years) were recruited for contact dissolution therapy. Pretreatment CT scans of the gallbladder were obtained in every patient under standard conditions. For contact dissolution treatment of heterogeneous gallstones or gallstones with attenuation values of more than 50 Hounsfield units, methyl tert-butyl ether and bile acid ethylene diaminetetraacetic acid were used in alternating administration at time intervals and durations adapted to the individual tolerance of the patients. In the case of gallstones with mean attenuation values under 50 Hounsfield units, the dissolution therapy was performed with methyl tert-butyl ether alone. In 12 (28.6%) patients a complete dissolution of gallbladder stones could be achieved; 11 patients (26.2%) revealed gallbladder sludge but no radiologically or sonographically visualized residual stone debris. The remaining 19 (45.2%) patients had residual gallstone debris. Shell fragments in three of five rimmed gallstones, seven of eight laminated gallstones, and all densely calcified stones were refractory to contact dissolution therapy. Dissolution rates correlated well with mean attenuation values, whereas no significant correlation was found between stone number and dissolution rates or between stone diameter and dissolution rates respectively. The mean instillation time required for stones with a mean density of more than 50 HU was 17.7 +/- 11.5 hr of bile acid ethylene diaminetetraacetic acid and 5.8 +/- 3.2 hr of methyl tert-butyl ether. In the case of isodense stones, the average instillation time of methyl tert-butyl ether was 12.3 +/- 4.7 hr.(ABSTRACT TRUNCATED AT 250 WORDS)

Bile Acids and Salts↗
PubMed1993

Effect of free fatty acids on the binding kinetics at the benzodiazepine binding site of glycated human serum albumin.

The effect of free fatty acids (FFA) and non-enzymatic glycation on the binding kinetics of dansylsarcosine (DS) to human serum albumin (HSA) was studied using the stopped-flow technique. The influence of FFA on the binding parameters of 25% glycated HSA depended on the type of fatty acid. The addition of stearic, oleic and linoleic acids in a concentration of 0.3 mmol/l showed no inhibitory effects on the association rate constant (k2) value for DS binding to 25% glycated HSA (k2 without FFA: 385 +/- 10 s-1, k2 with FFA > or = 385 +/- 10 s-1). In contrast, shorter chain fatty acids (hexanoic, octanoic, decanoic, lauric and myristic acids) showed marked inhibitory effects for 0.3 mmol/l FFA (k2 range: 233 +/- 32 to 69 +/- 5 s-1) and for 0.6 mmol/l FFA (k2 range: 125 +/- 3 to 20 +/- 4 s-1). The association rate constant (k2) as well as the affinity constant (KA) of DS were markedly affected by glycation: k2 was 686 +/- 61 s-1 for 7% glycated HSA, 385 +/- 10 s-1 for 25% glycated HSA and 209 +/- 12 s-1 for 50% glycated HSA. KA decreased from 6.1 +/- 2.9 x 10(5) M-1 for 7% glycated HSA, to 5.1 +/- 0.1 x 10(5) M-1 for 25% glycated HSA and to 1.3 +/- 0.6 x 10(5) M-1 for 50% glycated HSA.(ABSTRACT TRUNCATED AT 250 WORDS)

Benzodiazepines↗
PubMed1992

[Extracorporeal shockwave therapy in endoscopic therapy-refractory gallstones].

Extracorporeal shock-wave lithotripsy (ESWL) was undertaken in 36 patients (12 men, 24 women; mean age 70.9 +/- 2.4 years) with extra- or intrahepatic bile duct stones which could not be removed endoscopically. Stone fragmentation was successful in 32 patients with stones in the choledochal duct and in one with stones in the left hepatic duct. Fragmentation failed in two patients with stones in the left hepatic duct and one with stones in the cystic duct. 26 of the 36 patients were free of stone after spontaneous passage (n = 3) or after endoscopic removal of the residual concrements (n = 23). Complications occurred in only five patients during or after ESWL (cardiac arrhythmias, respiratory failure, pancreatitis, cholangitis).--These data point to ESWL being clearly preferable to surgical intervention in bile duct stones refractory to endoscopic treatment, especially in the elderly with an increased perioperative risk.

Aged↗
PubMed1992

The relationship between serum lipids, nucleation time, and biliary lipids in patients with gallstones.

The relationship between biliary lipids, cholesterol saturation index, nucleation time, and serum lipids was studied in a group of 45 gallstone patients (10 male, 35 female; age 50.1 +/- 14.5 years). Bile was obtained by direct fine-needle puncture of the gallbladder under local anesthesia and sonographic monitoring. No significant correlation between the serum lipids and either the cholesterol saturation index or total biliary cholesterol levels was observed. We found a positive correlation between the nucleation time and serum triglycerides content (r = 0.45, p = 0.0018) and a negative correlation between nucleation time and biliary cholesterol level (r = -0.38, p = 0.009). The fatty acids derived from the triglycerides are primarily resynthesized to phospholipids in the liver. When the supply of free fatty acids exhausts the metabolic capacity of the liver as, for example, in fat-rich diets, triglycerides accumulate in the liver cells and may possibly by excreted in the bile. Free fatty acids stimulate mucin hypersecretion in the gallbladder. This mucosal hypersecretion has been assigned a significant role in the formation of gallbladder stones. We also found a positive correlation between the total biliary bile acids and serum high density lipoprotein (HDL)-cholesterol in patients with a rapid nucleation time (r = 0.50, p = 0.0128). This supports the findings of other researchers, which suggests that HDL-cholesterol is devoted primarily to bile acid synthesis. In patients with a short nucleation time, the cholesterol saturation index, total lipid concentration, biliary cholesterol, mean age, and biliary bile acids were statistically different in comparison with patients with a prolonged nucleation time.

Aged↗
PubMed1992

Computed tomography after ESWL of gallbladder calculi.

Computed tomography (CT) was performed on 88 patients before and after extracorporeal shock wave lithotripsy (ESWL) of gallstones to find the effects of ESWL on the gallbladder and surrounding liver tissue. Post-ESWL scans demonstrated a thickening of the gallbladder wall in 25 (28.4%) cases. In one patient an intrahepatic bilioma beside the gallbladder was seen 3 days after ESWL treatment. Hematoma of the gallbladder wall or the adjacent liver tissue was not seen, and neither a hydrops nor biliary-induced pancreatitis was observed. The authors conclude that while some patients undergoing ESWL will show some posttreatment abnormality on CT scans, the procedure is associated with a low frequency of serious gallbladder and liver trauma.

Cholecystography↗
PubMed1992

Extracorporeal shock wave lithotripsy in symptomatic cholesterol gallbladder stone patients with a second generation electrohydraulic lithotripter (MPL-9000): experiences with 106 patients over 15 months.

One hundred and six patients were treated with a second generation underwater spark discharge lithotripter (Dornier MPL-9000). During the 15-month study period, Kaplan-Meier analysis predicted a stone clearance rate of 16.5% after 4 months, 37% (7 months), 71% (10 months), and 81% (15 months), respectively. Patients with multiple stones had a 5% probability to be free of stones after 13 months of treatment, when compared to 100% in patients with solitary stones smaller than 2 cm (p less than 0.001). Stones with densities below 100 Hounsfield units (HU) on computed tomography disappeared in 75% of the cases within 13 months. Rim calcified stones were cleared in 100% after 10 months of treatment. Fragmentation efficacy proved to be an essential predictive parameter for stone clearance: a fragment size below 5 mm after extracorporeal shock wave lithotripsy resulted in a 100% stone clearance within 13 months regardless of the initial stone number, size, and density. None of the stones fragmented to pieces of more than 10 mm in diameter could be dissolved within the observation period. Obviously, modern generation electrohydraulic lithotripters are effective in stone fragmentation, thus providing the basis for successful bile acid therapy provided the patients are properly selected.

Adolescent↗
PubMed1992

Increased gallbladder residual volume in nonresponders to extracorporeal shock wave lithotripsy of gallbladder stones.

In a prospective study of 63 patients, we purposed to determine whether gallbladder contractility or gallbladder volume before biliary lithotripsy are predictors of fragment disappearance. Percentage gallbladder contraction was calculated from the fractional difference in the sonographically measured gallbladder volume after a standard fatty meal. Statistical analysis showed no significant differences in gallbladder contractility between the fragment-free group and the residual-fragment group before (77.2 +/- 12.7% vs. 71.9 +/- 19.3%; p = 0.1044) biliary lithotripsy and after the termination of adjuvant cholelitholysis therapy (76.4 +/- 12.9% vs. 72.2 +/- 17.1%; p = 0.1341). Before treatment, there was no significant difference in fasting gallbladder volume in either group (29.9 +/- 15.4 ml vs. 36.6 +/- 18.8; p = 0.0682), but postprandial gallbladder volume was greater in nonresponders (10.4 +/- 9.4 ml vs. 6.5 +/- 3.8; p = 0.0164). After termination of the therapy, both the fasting gallbladder volume (41.2 +/- 24.2 ml vs. 29.8 +/- 10.3 ml; p = 0.0093) and the postprandial gallbladder volume (11.9 +/- 11.7 ml vs. 7.3 +/- 5.3 ml; p = 0.0267) were greater in the residual-fragment group. The increase of the fasting gallbladder volume in the residual-fragment group was statistically not significant. Our results indicate that the increased residual volume is a significant cause of therapeutic failure in nonresponders.

Chenodeoxycholic Acid↗
PubMed1992

Structured reporting of medical findings: evaluation of a system in gastroenterology.

A system using structured reporting of findings was developed for the preparation of medical reports and for clinical documentation purposes in upper abdominal sonography, and evaluated in the course of routine use. The evaluation focussed on the following parameters: completeness and correctness of the entered data, the proportion of free text, the validity and objectivity of the documentation, user acceptance, and time required. The completeness in the case of two clinically relevant parameters could be compared with an already existing database containing freely dictated reports. The results confirmed the hypothesis that, for the description of results of a technical examination, structured data reporting is a viable alternative to free-text dictation. For the application evaluated, there is even evidence of the superiority of a structured approach. The system can be put to use in related areas of application.

Attitude to Computers↗
PubMed1992

[Extracorporeal shock wave lithotripsy in patients with bile duct calculi].

21 patients with choledocholithiasis, in whom methods such as endoscopy or mechanical lithotripsy were unsuccessful, extracorporeal shock wave lithotripsy was performed. Fragmentation could be achieved in 90%, complete stone clearance after endoscopic stone extraction occurred in 76%. Extracorporeal shock wave lithotripsy has proven highly effective with a low complication rate and zero lethality. Therefore, its role in the management of gall stone disease in the elderly patient at high perioperative risk cannot be overemphasized.

Aged↗
PubMed1991

[Gallstone treatment by electrohydraulic extracorporeal shockwave lithotripsy].

Extracorporeal shockwave lithotripsy (ESWL) with an electrohydraulic system was performed in 124 patients (33 men, 91 women; mean age 50.1 +/- 12.7 years). Sufficient stone fragmentation was achieved in 122 patients (98.3%). ESWL was repeated in 29 patients (23.3%), twice in 7 patients (5.6%). Average shockwave application per patient was 1,441 +/- 414 impulses, at a mean energy of 20.0 +/- 1.6 kV. Mean stone diameter before ESWL was 16.2 +/- 4.2 (7-30) mm, 7.1 +/- 4.1 (0-19) mm after ESWL. Computed tomography, performed immediately after ESWL in 88 patients demonstrated hypodense thickening (3-10 mm) of the gallbladder wall in 28.4% of patients. This was interpreted as wall oedema, reversible in all. One patient had a covered gallbladder rupture and two had biliary pancreatitis. None of the patients required emergency surgery. 93 patients (74.9%) had no stones 12 months later. A high success rate can be achieved if certain criteria are adhered to and suitable patients are selected.

Adult↗
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

[Focal size and shock wave pressure: a comparison of three different physical shock wave generators].

Shock-wave delivery and focal size of three different generators-electrohydraulic, electromagnetic and piezoelectric--were compared. Pressure measurements were uniformly made by needle hydrophone (piezoelectric transducer). The smallest focus, 17 x 3 x 3 mm, was achieved with the piezoelectric system (50% isobars), while the focus with the electromagnetic generator was much larger (50 x 7 x 4 mm). With the electrohydraulic generator the focal size of the 60% isobars was 20 mm in the longitudinal axis. The highest pressure, 1512 bar, was achieved with the piezoelectric lithotriptor (mean shock-wave pressure in focus: electrohydraulic 1000 + 100, electromagnetic 1000 + 25, piezoelectric 1400 + 27 bar). The rapid positive pressure rise was followed by a slower pressure fall and a small negative wave. In the focal region the negative pressure wave was between 112 and 200 bar with the electrohydraulic system, 100-146 bar with the electromagnetic one, and 134 bar with the piezoelectric one. The significance of the negative wave is not clear; perhaps it contributes to the development of the cavitation effect and facilitates stone fragmentation.

Electromagnetic Phenomena↗