Lithostar Plus Research Articles

In vitro investigations on cellular damage induced by high energy shock waves.

Single-cell suspensions of the prostate carcinoma cell line PCA were exposed to electromagnetically generated ultrasound shock waves (source and focusing lens identical to those used in the commercially available lithotripor Lithostar Plus). Cell loss of up to 40% occurred in sample tubes containing air. To expose multicellular tumor spheroids and cells growing on a microcarrier, an experimental setup was developed that prevented motion of the specimen. Intracellular damage of intact spheroids was analyzed by laser scanning microscopy following specific fluorescence staining. Different sensitivities of individual cell components with respect to the applied energy density of the pulses were found, namely defects on cell membranes (0.12 mJ/mm2), vimentin (0.21 mJ/mm2), mitochondria (0.33 mJ/mm2) and nuclear membranes (0.5 mJ/mm2). Loss of cells growing on a microcarrier was found after application of 200 pulses with 0.21 mJ/mm2.

Extracorporeal Shock Wave Lithotripsy in Horseshoe Kidneys

Presentation of our experience in the use of extracorporeal shock wave lithotripsy (ESWL) for the treatment of lithiasis that occurred in 34 renal units from 28 patients with horseshoe kidneys. All patients but one were placed in supine decubitus with the calculus positioned in F2. A total of 47 sessions were performed for 34 treatments apart from 3 ureteroscopies for ureteral voiding. The results of the follow-up is absence of lithiasis in 13 renal units, debris of less than 3 mm in six, non-removable debris in 13 cases and relapse in two.

Gallstone lithotripsy: results when number of stones is excluded as a criterion for treatment.

The Siemens Lithostar Plus protocol (Siemens Medical Systems, Iselin, NJ) allows investigators to perform gallstone lithotripsy on patients regardless of the number of stones they have, provided the stones occupy less than 50% of the gallbladder lumen. The purpose of this study was to determine the interrelationships between stone burden, fragmentation response, and stone-free rates when treatment is not limited to three stones or fewer. Of 200 patients initially examined, 80 (40%) underwent lithotripsy. The mean number of treatments per patient was 2.1, and the mean number of shock waves per patient was 7386. In 60 patients in whom 6-month follow-up was available, the overall stone-free rate, based on actual results, was 32% (19/60). The stone-free rates for solitary stones, two or three stones, and four or more stones were 50%, 12%, and 26%, respectively. Regardless of number of stones, patients who ultimately became stone free had significantly smaller mean fragment size (0.25 cm) 2 weeks after lithotripsy than did those who did not become stone free (0.51 cm). Retrospective volume analysis showed that seven (47%) of 15 patients with multiple stones occupying less than 2000 mm3 were stone free; none became stone free when this volume was exceeded. Lithotripsy remains a practical option for patients with solitary stones. Comparable stone-free rates to those achieved for solitary stones can be obtained in patients with multiple stones, regardless of their number, provided treatment is aggressive and the stone aggregate is less than 2000 mm3.

Effectiveness of Transcutaneous Electrical Nerve Stimulation (TENS) for Analgesia during Biliary Lithotripsy

The effectiveness of transcutaneous electrical nerve stimulation (TENS) in controlling pain during biliary extracorporeal shockwave lithotripsy (BESWL) was assessed in 100 patients with symptomatic gallbladder calculi. Patients were divided into four groups: TENS electrodes were placed on the back at cutaneous anesthesia sites and on the right leg and the gallbladder acupuncture site in groups A and B. Electrodes were "turned on" only in group A. In groups C and D, electrodes were placed only on the back at cutaneous dermatomes. Electrodes were "turned on" in group C only. The TENS unit was stimulated at the pulse rate of 60 to 100 microseconds and frequency of 80 to 125 Hz. Lithotripsy was performed with the Lithostar Plus overhead module. The differences in the amount of analgesic used and the pain experiences by the patients in all groups were not statistically significant. The proportion of patients requiring intravenous analgesia in each group was also not significantly different (72%, 80%, 68%, 76% in groups A to D, respectively). Thus, TENS did not help in reducing the amount of intravenous analgesia required or the average pain perceived by the patient during lithotripsy treatment.

In vitro fragmentation of gallstones: Comparison of electrohydraulic, electromagnetic and piezoelectric shockwave lithotripters

To compare the fragmentation efficiency of three different shockwave systems, 63 human gallstone triplets were disintegrated in vitro using an electrohydraulic (MPL 9000, Dornier), an electromagnetic (Lithostar Plus, Siemens) and a piezoelectric (Piezolith 2300, R. Wolf) lithotripter. Since each stone triplet was obtained from the same gallbladder, the concrements of one such set were identical in physicochemical parameters. According to the maximal diameter, the calculi were divided into group A (6 to 15 mm) and group B (16 to 30 mm). Shockwave application was terminated when residual fragments measured 4 mm or less. Forty-five triplets were fragmented at energy settings mainly used in clinical treatment of patients with gallbladder stones (MPL 9000: 20 kV; Lithostar Plus: setting 9 (maximal); Piezolith 2300: setting 3). The fragmentation endpoint was achieved in group A (n = 3 × 36) with the Piezolith 2300 after median 150 (range = 50 to 500) pulses and with the Lithostar Plus after 150 (50 to 750) pulses compared with 500 (50 to 1,500) pulses using the MPL 9000 (p < 0.01). In group B (n = 3 × 9) the Lithostar Plus (median = 750, range = 250 to 1,250 pulses) required fewer discharges than the Piezolith 2300 (1,250,250 to 2,500 pulses; p < 0.05) and the MPL (1,500,500 to 1,600 [upper limit] pulses; p < 0.01). At maximal intensities (MPL 9000: 26 kV; Lithostar Plus: setting 9; Piezolith 2300: setting 4), no statistically significant differences between the three tested shockwave systems were observed (Piezolith 2300: 100, 50 to 250 pulses; MPL 9000: 100, 50 to 500 pulses; Lithostar Plus: 100, 50 to 1000 pulses) for group A stones (n = 3 × 12) and group B stones (n = 3 × 6; Piezolith 2300 [500, 250 to 750 pulses], MPL 9000 [625,250 to 750 pulses] and Lithostar Plus [750, 250 to 1,000 pulses]). An adequate degree of fragmentation independent of the physical shockwave system can be achieved in vitro at maximal intensities for each tested stone size. At submaximal energy settings, better results were obtamed in stones up to 15 mm in diameter with the piezoelectric generator than with the electrohydraulic device, whereas in larger stones disintegration efficiency did not differ significantly between these two lithotripters. (HEPATOLOGY 1991;14:301–305.)

In vitro fragmentation of gallstones: Comparison of electrohydraulic, electromagnetic and piezoelectric shockwave lithotripters

To compare the fragmentation efficiency of three different shockwave systems, 63 human gallstone triplets were disintegrated in vitro using an electrohydraulic (MPL 9000, Dornier), an electromagnetic (Lithostar Plus, Siemens) and a piezoelectric (Piezolith 2300, R. Wolf) lithotripter. Since each stone triplet was obtained from the same gallbladder, the concrements of one such set were identical in physicochemical parameters. According to the maximal diameter, the calculi were divided into group A (6 to 15 mm) and group B (16 to 30 mm). Shockwave application was terminated when residual fragments measured 4 mm or less. Forty-five triplets were fragmented at energy settings mainly used in clinical treatment of patients with gallbladder stones (MPL 9000: 20 kV; Lithostar Plus: setting 9 (maximal); Piezolith 2300: setting 3). The fragmentation endpoint was achieved in group A (n = 3 x 36) with the Piezolith 2300 after median 150 (range = 50 to 500) pulses and with the Lithostar Plus after 150 (50 to 750) pulses compared with 500 (50 to 1,500) pulses using the MPL 9000 (p less than 0.01). In group B (n = 3 x 9) the Lithostar Plus (median = 750, range = 250 to 1,250 pluses) required fewer discharges than the Piezolith 2300 (1,250, 250 to 2,500 pulses; p less than 0.05) and the MPL (1,500, 500 to 1,600 [upper limit] pulses; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Extracorporeal Shock Wave Lithotripsy of Urinary Calculi: Experience in Treatment of 3,278 Patients Using the Siemens Lithostar and Lithostar Plus

Between March 1986 and June 1989, 3,278 patients with upper urinary tract calculi were treated at our medical center with the Lithostar**Siemens Medizinische Technik, Erlangen, Germany. lithotriptor. The stones were located in the calices in 41.9% of the cases, renal pelvis in 25.7% and ureter in 32.4%. Perirenal hematoma was noted in 0.5% of the patients but this resolved spontaneously within a few days. Auxiliary procedures were performed in 37.3% of the cases, including Double-J stent††Medical Engineering Corp., New York, New York. and ureteral catheter in 26.8%, ureterorenoscopy in 2.1%, percutaneous nephrostomy in 1.6%, Zeiss loop in 4.3% and percutaneous nephrolithotripsy in 3.5%. Of the treatments 83.1% were performed without general or regional anesthesia. Followup after 3 months showed a 63.8% rate free of stone.The Lithostar upgraded with the overhead lithotripsy module is called Lithostar Plus. A total of 25 patients with upper urinary stones underwent treatment with the overhead module. Initial experience revealed fragmentation of stones after the first session in 20 patients, while a second session was necessary in 5. Analgesic sedation was used in 4 patients in whom a Double-J stent was inserted.

Electromagnetically Generated Extracorporeal Shock Wave Lithotripsy and Adjuvant Combined Oral Litholysis for Therapy of Symptomatic Gallbladder Stones

A prospective study was conducted to evaluate effectivity, problems and adverse effects of extracorporeal shock wave lithotripsy (ESWL) using a newly developed electromagnetic biliary lithotriptor (Lithostar Plus, Siemens, Erlangen, FRG) for the treatment of selected patients presenting with symptomatic cholecystolithiasis. In addition to generally accepted criteria for the selection of patients, gallbladder contractility was established and pigment stones were excluded by computed tomography (CT). 80 out of 486 patients (63 females, 17 males, mean age 36, range 17-76 years) were selected for ESWL using a standardized diagnostic program. 62 out of 80 patients participating in the study had solitary concrements (diameter 23.3 +/- 6.4 mm) while in 18 patients 2 or 3 stones (diameter below 10 mm) were observed. Stone fragmentation was achieved after an average of 1.35 treatment sessions (range 1-3) in 78 (97.5%) patients. No clinically relevant adverse effects were observed. Immediately after ESWL, ultrasound revealed misleading results with regard to stone fragmentation. 98.7% of patients (n = 77) were seen for follow-up investigations 3, 6 and 9 months after ESWL, and 82% at 12 months. A total of 40 (53%) patients became free of stones. Subgroup analysis showed that 68% of the patients were free of stones (stone diameter 10-20 mm), 54% (20-30 mm) and 33% (multiple stones), respectively. We therefore conclude that ESWL should be restricted to highly selected patients presenting with small (10-20 mm) solitary concrements.

Long-term soft-tissue effects of biliary extracorporeal shock waves: an animal study.

Although delayed effects of renal extracorporeal shock-wave lithotripsy (ESWL) have been reported, the long-term soft-tissue effects after biliary ESWL have not been investigated. We report soft-tissue effects seen up to 1 year after biliary extracorporeal shock waves were administered to 18 Yucatan pigs. The gallbladder received 4000 electromagnetic shock waves from a Siemens Lithostar overhead module. Blood samples were drawn from each pig for hematologic, coagulation, and biochemical profiles immediately before and then at prescribed time intervals after administration of shock waves. Autopsy and histopathologic examination of the gallbladder and surrounding organs were performed. Kidneys and adrenal glands also were examined in five pigs followed up for 1 year. There were no gross or microscopic abnormalities in 11 animals, including all five animals in the 1-year group in which kidneys and adrenal glands also were normal. One animal (3-week group) had two 2-mm foci of parenchymal necrosis in the right lobe of the liver, probably related to ischemia after shock-wave therapy. Transient rise in liver and pancreatic enzyme levels was seen in most animals after administration of shock waves. The levels returned to normal within 2 months in all but one animal. We conclude that biliary ESWL with the Lithostar Plus does not produce long-term histologic evidence of organ damage in Yucatan pigs.

Routine liver function tests and serum amylase determinations after biliary lithotripsy: are they necessary?

Shock-wave-induced soft-tissue damage after biliary extracorporeal shock-wave lithotripsy (BESWL) has been reported. Every patient treated in Vancouver has, therefore, had liver function tests and serum amylase levels measured before and within 6 days after BESWL. All patients had symptomatic cholecystolithiasis with normal pre-BESWL biochemistry. Analysis of 311 patients after treatment with the Siemens Lithostar unit showed elevation of one or more laboratory value in 19% (60/311). Serum aspartate transaminase level was most frequently abnormal (38 cases). The majority of abnormalities were mild, less than two times normal levels. Clinically significant complications occurred in five patients (three pancreatitis, one cholecystitis, one common bile duct obstruction); four of these occurred 1 week or more after treatment. The results of routine laboratory tests could not be used to predict complications. No correlation was seen between abnormal values and number of shock waves administered or peak shock-wave pressure. Of 112 patients surveyed at the time of post-BESWL enzyme measurement, 49 (44%) reported a degree of pain, which was severe in eight cases. Presence of severe pain correlated strongly (p less than .001) with abnormal laboratory findings, however not with the degree of abnormality. As results of these laboratory tests are nonspecific, have not been shown to correlate with the degree of severity of BESWL-induced tissue damage, and do not predict complications, the tests are of little value in the absence of clinical signs and symptoms. These conclusions, however, apply only to the Siemens Lithostar Plus with patients treated in the steep left posterior oblique position. Cost savings can be expected if routine post-BESWL biochemical tests are abandoned.