The Journal of stone disease最新文献

In order to facilitate laparoscopic cholecystectomy in the presence of large gallbladder stones seven patients underwent ESWL before operation. In six cases (83%) a fragmentation to less than or equal to 1 cm could be achieved by application of 1,605 to 2,900 (mean 2,266) shock waves with the spark-gap lithotripter Philips-Dornier MFL 5000. In these cases intraoperative stone destruction or an increase of the puncture incision size could be avoided, thus proving the efficacy of this combined treatment approach. Laparoscopic inspection was performed 2 to 48 hours after ESWL. Including two additional cases operated because of unsuccessful ESWL, hematomas of the liver and adjacent organs were observed in six of nine patients (67%). This high rate of subclinical tissue lesions warrants caution if repeated ESWL sessions are scheduled at short-term intervals.

Several different piezoelectric lithotripters have been under clinical investigation for gallstones in the USA. Design differences in the different shock wave generators result in different characteristics for the three devices and different peak pressures at the focus of the lithotripters. Using gallstone families, we sought to study fragmentation in the three lithotripters. A total of 56 gallstones from eight gallstone families were studied. Forty-eight stones were fragmented in three lithotripters (16 in each), Diasonics (Therasonic), EDAP (LT01), and Wolf lithotripter (Piezolith 2300), at maximum power and a rate of 2-2.5 Hz. A total of 500 shocks was applied to each stone in each of the three lithotripters. Gallstone composition was determined by infrared spectroscopy on one stone of each family (8 x 1). Initial stone weight and size were similar in all the three groups. All families consisted of cholesterol stones ( greater than 70% cholesterol). The fraction of the initial stone mass reduced to fragments less than or equal to 2 mm was not significantly different in the three lithotripters (Diasonics [n = 16] = 60 +/- 4%, EDAP [n = 16] = 53 +/- 6%, Wolf [n = 16] = 50 +/- 7%; p = 0.068).(ABSTRACT TRUNCATED AT 250 WORDS)

Minimally invasive surgical procedures are particularly desirable in patients with cystine stones because of their often multiple previous operations, complicated stone situations, and high risk of recurrences. Twenty-four treatment episodes for cystine stones were carried out, 12 with extracorporeal shock wave lithotripsy (ESWL) as monotherapy and 12 with a combination of ESWL and percutaneous irrigation with chemolytic solutions. In the ESWL monotherapy group, five of 12 renal units became stone-free and one more patient was discharged stone-free, except for an untreated stone in a calix diverticulum. Combined treatment, most often given in association with more complicated stone situations, rendered seven out of 12 kidneys stone-free. Even in this group, one patient was discharged with an untreated residual stone in a calix diverticulum. Our results show that even complicated cystine stone situations can be successfully treated in a minimally invasive way, with the best results obtained with a combination of ESWL and percutaneous chemolysis. Alkalization of urine seemed to be insufficient in preventing stone formation. No difference in recurrence rate was observed between our two treatment groups.

A total of 225 human gallbladder stones were divided into sets of two, three, or four identical calculi (with maximum diameters of 6-26 mm) and submitted to piezoelectric shock wave lithotripsy in vitro in order to investigate the influence of the following parameters on stone disintegration: shock wave intensity, pulse frequency, and various physicochemical parameters such as the volume and viscosity of the fluid surrounding the stone, the hardness of the calculus, and its chemical composition. The fragmentation efficacy increased with enhanced shock wave energy (P less than 0.01). If the volume of the fluid (30 mL) surrounding the calculus was small, the disintegration end-point (defined by maximum fragment diameters less than or equal to 4 mm) was achieved after a lower number of pulses (median: 250 pulses) than in the case of a large fluid volume (80 mL) (500 pulses; P less than 0.01). On the other hand, however, factors such as the shock wave pulse rate (0.9 Hz vs 1.6 Hz), variations in viscosity of a water-jelly mixture surrounding the stone, the chemical composition of the stones as determined by X-ray diffractometry, and stone hardness were found to have no significant influence on the fragmentation efficacy.

In an attempt to identify potentially lithogenic proteins, a detergent soluble extract of human renal calculi was used to produce a unique monoclonal antibody. The monoclonal antibody was found to detect the presence of a specific epitope in 77% of individually extracted kidney stones from our patients' stone bank at The Long Island Kidney Stone Unit, State University of New York, Stony Brook. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoprecipitation, and Western Blot analysis revealed this monoclonal antibody to be specific to a protein of 83,000 dalton molecular weight. A secondary source of protein reactive to the monoclonal antibody was subjected to enzyme kinetic studies, those studies suggested that the 83,000 dalton protein is a member of the protein-glutamine gammaglutamyltransferase (transglutaminase) family of enzymes. It was not determined in the present investigation whether a member of this family of enzymes initiates or is necessary for lithiasis.

The Dornier MPL-9000 lithotripter was analyzed as a function of lithotripter voltage, electrode efficiency, and bovine muscle attenuation. The maximum pressure at 20 kV measured 65 +/- 4 MPa (mean +/- SD). The region containing 50% of the maximum pressure was a cylindrical volume with a diameter of 2.5 cm and a height of 7 cm. Pressure varied in a linear fashion with lithotripter voltage (r = 0.996). The average pressure produced by an electrode throughout the course of 2,200 shock waves was 78% of its maximum pressure. Shock wave pressure was reduced from 65 +/- 4 MPa to 49 +/- MPa, 44 +/- 3 MPa, and 44 +/- 1 MPa with 1-, 2-, and 3-cm thickness of intervening bovine muscle, respectively. There was a statistically significant decrease in pressure when muscle was interposed, but there was no significant difference in reduction of pressure between 1, 2, and 3 cm of muscle (ANOVA, Newman-Keuls, alpha = 0.01). Frequency spectral analysis revealed the major contribution to the shock wave comes from 0-200 kHz with a peak near 50 kHz. Major frequency intensities were reduced with a decrease in lithotripter voltage, attenuating tissue, and distance away from the center of the focal zone.

Clinical extracorporeal shock wave lithotripsy (ESWL) results have shown that the smaller the gallstone fragments following ESWL, the faster the patient will become stone-free. At ESWL, an attempt is made to produce sand-like fragments that will easily pass through the cystic and common bile ducts. Sixteen pairs of gallstones of equal shape, size, and composition were harvested from cholecystectomy specimens and then fragmented on the Dornier MPL-9000 lithotripter (Dornier Medical Systems, Inc.), individually, in a phantom oriented to duplicate either supine or prone patient positions. The number and size of remaining fragments were compared following the supine versus prone treatments. The 32 stones, ranging from 5-15 mm in diameter, received 1,500 shock waves at 21 kV. Fragments with a maximal diameter of greater than or equal to 4 mm were measured and counted after 750 and 1,500 shock waves. Fragments greater than or equal to 4 mm were found in four out of 16 stones treated supine (25%) and 16 out of 16 stones treated prone (100%). The largest residual fragment regardless of size for each stone pair occurred in the prone group in 14 out of 16 cases (88%). Biliary lithotripsy performed with supine positioning results in more efficacious gallstone fragmentation in this in vitro model; these findings suggest that supine positioning for patients could improve fragmentation and treatment success.

Fifty-three patients were treated in the prone position for stones located in the pre-sacral ureter. Cases were performed at the Orange County Kidney Stone Center by 28 urologists from March 1988-November 1989. A Dornier HM-3 Lithotripter with the original generator, 15.6-cm ellipse, and computerized gantry was used. No repeat treatment was utilized in this series and three failures resulted.

Numerous, large, or calcified gallstones hinder successful extracorporeal fragmentation. The purpose of this study was to investigate an in vitro method that could accelerate the destruction of these types of gallstone burdens. Matched sets of partially calcified gallstones, each set having a combined stone diameter greater than 3 cm, underwent lithotripsy while immersed in either 15 cc of bile, methyl t-butyl ether (MTBE), or dimethyl sulfoxide (DMSO), with a fourth set serving as a control. Results showed a 20% reduction in the relative weight of all fragments, an eightfold reduction of the relative weight of fragments greater than 3 mm, and a 50% reduction of the number of large fragments when the stones were immersed and shocked in MTBE rather than when shocked in bile. Dimethyl sulfoxide hindered gallstone destruction. These results indicate that large, partially calcified gallstone burdens can be more successfully destroyed if lithotripsy is performed in the presence of a small quantity of MTBE rather than in bile alone or in the presence of DMSO. If proven safe in vivo, this technique could expand the applicability of lithotripsy to those with larger, partially calcified stone burdens.