Lithotripsy Therapy Research Articles

Percussion, diuresis, and inversion therapy for the passage of lower pole kidney stones following shock wave lithotripsy

Lower pole kidney stones typically have poor rates of spontaneous clearance from the body. Some studies have suggested that diuresis, percussion and inversion therapy could be beneficial for people with lower pole kidney stones following shock wave lithotripsy. There is however controversy about the relative benefits, harms, and efficacy of these interventions for the management of lower pole kidney stones. To identify the benefits and harms of percussion, diuresis, and inversion therapy to facilitate the passage of lower pole kidney stones following shock wave lithotripsy. We searched the Cochrane Renal Group's specialised register up to 27 November 2013 through contact with the Trials' Search Co-ordinator using search terms relevant to this review. All randomised controlled trials (RCTs) and quasi-RCTs looking at the benefits and harms of percussion, diuresis, and inversion therapy for aiding passage of lower pole kidney stones following shock wave lithotripsy were sought for assessment. The first phases of randomised cross-over studies were also eligible for inclusion. Two authors independently assessed study quality and extracted data. Results were expressed as relative risk (RR) for dichotomous outcomes and mean difference (MD) or standardised mean difference (SMD) for continuous data with 95% confidence intervals (CI). We identified two small studies (177 participants) for inclusion and analysis. One study (69 participants) compared percussion, diuresis and inversion therapy following shock wave lithotripsy versus observation-only after shock wave lithotripsy. This study reported significantly higher stone-free rates in the intervention group (RR 0.62, 95% CI 0.47 to 0.82) and a significant reduction in stone burden (MD -3.30, 95% CI -3.58 to -3.03) compared to the observation-only group. They reported no significant differences in complication rates (RR 3.00, 95% CI 0.12 to 76.24).The second study (108 participants) compared percussion, diuresis, and inversion therapy plus shock wave lithotripsy with shock wave lithotripsy therapy alone. This study reported significantly higher stone-free rates in the intervention group (RR 0.36, 95% CI 0.17 to 0.80) and a significant reduction in stone burden (MD -0.30, 95% CI -0.04 to -0.56) compared to the control group. They reported no significant differences in complication rates (RR 2.54, 95% CI 0.10 to 63.72).For both studies selection bias was unclear; there was high risk of bias for performance bias; and detection, attrition and reporting bias were low. Limited evidence from two small studies indicated that percussion, diuresis, and inversion therapy may be safe and effective therapies to assist clearance of lower pole kidney stone fragments following shock wave lithotripsy. Methodological quality in both studies was assessed as moderate. Further well-designed and adequately powered studies are required to inform clinical practice.

The need for additional equipment after ESWL in ureteroscopic lithotripsy

Objective: This study evaluated our results with ureteroscopic lithotripsy (URS) in patients with failed extracorporeal shock wave lithotripsy therapy (ESWL) and examined the effect of previous ESWL on the use of tools during URS, operating time, and outcome. Materials and methods: URS performed in two centers between 2008 and 2011 was reviewed retrospectively. The patients were divided into two groups according to the history of previous ESWL: 1) patients who underwent ESWL previously (n=39) and 2) no previous ESWL (n=116). Results: The demographic data were similar in both groups. The use of accessory tools and treatment failure was statistically higher in Group 1. The operating time was longer in Group 1. The need for re-operation, balloon dilatation, and ureteral catheter was similar in the two groups. However, the use of accessory equipment was increased by 56% in those with a previous ESWL. Balloon dilatation was required in 17.9% of the patients in Group 1. Conclusion: URS is the main treatment modality after the failure of ESWL. In patients with a history of ESWL, the need for accessory equipment is increased.

Surgical management for urolithiasis

The indication of the surgical management for urolithiasis isn't decided only in the size of the stone. Even the small stone sometimes influences a kidney function and clinical symptom. Present Japanese surgical treatment for Urolithiasis is almost lithotripsy therapy. Though most of lithotripsy therapy is ESWL, TUL and PNL were chosen due to the state of the stone.

Diagnostic value of B type ultrasound in ureteral calculi

Objective To evaluate the diagnostic value of B type ultrasound in ureteral calculi. Methods B type ultrasound examination were performed on 100 cases with ureteral calculi who were confirmed by open surgery, extracorporeal shock wave lithotripsy and comprehensive therapy. Results The diagnostic accuracy was 94. 00% in 100 cases,no false positive was found,and the rate of missed diagnosis was 6.00% (6 cases). Conclusion B type ultrasound has a high application value in the diagnosis of ureteral calculi, which has low false positive rate and can clear display negative stone. It can also afford some accurate clues for diagnosis and clinical treatment in tihe according to abdomenal B type ultrasound and it will be preferred in way for diagnosis of acute nephrite colic especially in basic hospitals. Key words: Ureteral calculi; B type ultrasound; Missed diagnosis

Laser-induced lithotripsy and photodynamic therapy in urology – A short introduction to current laser applications

Abstract Laser-induced lithotripsy and photodynamic therapy (PDT) are among the most important laser applications in urology. Laser lithotripsy has revolutionized urinary calculi treatment. Today, Ho:YAG laser lithotripsy using a small-caliber ureteroscope can be considered to be the first choice for treatment of ureteral calculi. In contrast to laser-induced lithotripsy, PDT is not yet firmly established in urological clinical routine. However, preclinical and clinical trials with PDT in urology are showing promise in the treatment of malignancies at multiple sites. The present article gives a review of the literature from both fields and discusses the current status of laser lithotripsy and PDT in urology.

Percutaneous Nephrolithotomy in Children

To review the history of percutaneous nephrolithotomy (PCNL) in children, describe technical considerations, including advancements in equipment, and discuss future directions. A comprehensive literature review was performed using MEDLINE/PubMed to evaluate the use of PCNL in the pediatric population, including historical background, indications, operative techniques, and outcomes. PCNL was first applied to the pediatric population in the 1980s using adult-size instruments. Although there is still concern for potential renal damage in relatively small kidneys, initial investigations have demonstrated its safety and efficacy in children. Operative techniques are similar to those used in adult patients, but considerations specific to pediatric populations must be addressed. Modifications in technique including "mini-perc" access have reduced postoperative morbidity without an appreciable difference in outcomes. Technologic improvements, including miniaturization of endoscopes and advances in energy sources for stone fragmentation, have facilitated stone-free rates comparable to those of adult populations with PCNL monotherapy and sandwich shockwave lithotripsy therapy with minimal postoperative morbidity. Technologic advancements and refinements in technique have facilitated the successful application of PCNL in the pediatric population. As a result, PCNL has now replaced open surgery as the treatment of choice for large stone burdens in children of all ages.

Time reversal of monochromatic signals in elastic media.

A set of experiments has been conducted to show that time reversal of steady state monochromatic signals can produce spatial focusing in a reverberant elastic cavity when multiple channels are used. The transient portion of the received signals is not used. A single channel does not produce spatial focusing as it only drives the system according to its modal distribution. The amplitude of the energy at the focal location increases as the square of the number of channels used, while the amplitude elsewhere in the medium increases proportionally with the number of channels used. This work has importance in the field of medical ultrasound where the use of a long duration monochromatic excitation may be used for lithotripsy or other ultrasonic therapy. [This work is supported by Institutional Support (LDRD) at Los Alamos National Laboratory.]

膵石症に対するESWLと内視鏡的治療の適応と限界

膵石症に対するESWLと内視鏡的治療の適応と限界

膵石症に対するESWLと内視鏡治療後の膵内外分泌機能の変化

膵石に対する体外衝撃波結石破砕療法（ESWL）と内視鏡治療は，その低侵襲性ゆえに近年，臨床応用が盛んに行われている．当科における治療成績でも，両者を併用することにより破砕効果97%，完全排石56%，疼痛改善効果97%であり，特に治療後の疼痛改善効果に優れていることが示されている．一方，膵外分泌機能に関しては，膵石治療後短期的には改善する症例が多かったが，長期経過では，膵外分泌機能，膵内分泌機能ともに低下する症例が多かった．特にアルコール性慢性膵炎での飲酒継続群では低下する傾向が顕著であった．

Long-term evaluation of extracorporeal shock wave lithotripsy in the treatment of salivary stones

Extracorporeal shock wave lithotripsy is a rather new therapeutical method in the treatment of sialolithiasis. The objective was to evaluate retrospectively the results of the extracorporeal shock wave lithotripsy therapy performed with a Minilith SL 1 lithotripter on 167 out-patients with symptomatic stones (average size 5.94 mm) of the salivary glands over an observation period of seven years. A successful treatment with total stone disintegration was achieved in 51 (31 per cent) patients. In 92 (55 per cent) patients treatment was partially successful, with disappearance of the symptoms but a sonographically still identifiable stone. Treatment failure occurred in 24 (14 per cent) patients who then underwent surgery. The mean follow-up period was 35.6 months (minimum three, maximum 83), after which 83.2 per cent of the initially successfully treated patients were still free of symptoms.Therefore, extracorporeal shock wave lithotripsy, as a non-invasive treatment alternative with few side effects, is an efficient technique for the therapy of sialolithiasis in selected patients.

Multiorgan Failure 17 Years after Initial Stone Therapy: Forgotten Ureteral Stent in a Horseshoe Kidney

We report on the case of a 44-yr-old white man who was referred as an emergency from a local hospital to the medical intensive care unit (ICU) at our institution for progressive multiorgan failure of unknown cause. The CT scan of the abdomen showed a horseshoe kidney with extensive stone formation in both kidneys and the urinary bladder. A massively calcified double pigtail ureteral stent could also be seen in the left upper urinary tract. The stent had been placed prior to extracorporeal shock wave lithotripsy (ESWL) therapy 17 years previously. Three weeks later, after conservative treatment for heart failure and septic complications, the massively enlarged hydronephrotic left part of the horseshoe kidney was exposed and heminephroureterectomy was performed. Moreover, a right-sided pyelotomy was performed. Midline vesicotomy allowed extraction of the remaining bladder stone including the rest of the forgotten pigtail stent. The patient recovered rapidly after surgery and was discharged after 2 wk with all drains removed.

Gallstone clearance: A randomized study of extracorporeal shock wave lithotripsy and chemical dissolution

Following extracorporeal shock wave lithotripsy it is not known whether gallstone fragments are cleared from the gallbladder without the use of oral dissolution therapy. To assess the efficacy of lithotripsy and dissolution therapy, alone or in combination, 35 patients were randomized to one of three treatment groups: lithotripsy alone, dissolution therapy alone or combined lithotripsy and dissolution therapy. All patients had symptomatic gallstones, functioning gallbladders and comparable stone profiles. Lithotripsy was administered using a piezoelectric lithotripter. Dissolution therapy consisted of combined bile acid and terpene. Clearance was assessed at 6 months using ultrasound and oral cholecystography. Patients with less than 50 per cent stone clearance at the end of 6 months were considered failures. The number of patients with total or partial clearance in the combined group (7/10) was significantly greater than those in the lithotripsy alone group (0/10, P less than 0.002). Gallstone clearance following lithotripsy appears to be dependent upon dissolution therapy.

Gallstone clearance: A randomized study of extracorporeal shock wave lithotripsy and chemical dissolution

Following extracorporeal shock wave lithotripsy it is not known whether gallstone fragments are cleared from the gallbladder without the use of oral dissolution therapy. To assess the efficacy of lithotripsy and dissolution therapy, alone or in combination, 35 patients were randomized to one of three treatment groups: lithotripsy alone, dissolution therapy alone or combined lithotripsy and dissolution therapy. All patients had symptomatic gallstones, functioning gallbladders and comparable stone profiles. Lithotripsy was administered using a piezoelectric lithotripter. Dissolution therapy consisted of combined bile acid and terpene. Clearance was assessed at 6 months using ultrasound and oral cholecystography. Patients with less than 50 per cent stone clearance at the end of 6 months were considered failures. The number of patients with total or partial clearance in the combined group (7/10) was significantly greater than those in the lithotripsy alone group (0/10, P less than 0.002). Gallstone clearance following lithotripsy appears to be dependent upon dissolution therapy.

Extracorporeal shockwave lithotripsy and litholytic therapy in cholelithiasis.

Extracorporeal shockwave lithotripsy (ESWL) and litholytic therapy were used in 100 patients over a period of 16 months. ESWL was carried out with a Lithostar Plus and chenodeoxycholic acid was used as the lytic agent, given until 3 months after complete disappearance of stones. Within a period of 8-12 months, stones disappeared completely in 82 per cent of the patients who had a single stone less than or equal to 20 mm in diameter and in 50 per cent of those with a single stone greater than 20 mm in size or with multiple stones. Complications requiring surgery developed in five patients: three had acute cholecystitis and two developed acute pancreatitis. Of the patients in whom complete stone clearance was achieved, two of 11 followed up developed recurrence of stones 4 months after cessation of lytic therapy.

RIGID URETEROSCOPY FOR THE TREATMENT OF URETERAL CALCULI IN CHILDREN

We assess the safety and efficacy of rigid ureteroscopy for the treatment of pediatric ureterolithiasis. The records of 33 children with an average age of 7.4 years (range 9 months to 15 years) treated with rigid ureteroscopy between May 1995 and July 2003 were reviewed. In 35 ureteral units use of a rigid 6.9 to 10Fr ureteroscope was planned for treating stones at various levels of the ureter. Stones were located in the upper ureter in 6 cases, middle ureter in 3 and lower ureter in 26. Dilatation of the ureteral orifice was necessary in 11 cases. Stone size varied from 3 to 10 mm (mean 5.3). In 33 patients (94%) all stone fragments were removed successfully. Stones were fragmented with pneumatic lithotripsy in 20 cases and removed by forceps without fragmentation in 13. In 1 child an upper ureteral stone migrated up to the kidney during ureteroscopy but following extracorporeal shock lithotripsy therapy she was rendered stone-free. In another child it was not possible to remove the stone. In a 9-month-old female patient with bilateral stones it was not possible to enter the left ureter because of a tight orifice resistant to balloon dilation. At the end of the procedure a 3 or 4Fr ureteral or a 4.8Fr Double-J (Medical Engineering Corp., New York, New York) stent was left in place for 3 days to 3 weeks in 12 cases. There were no cases of ureteral perforation. Of the patients 31 were followed for 1 to 36 months. No incidence of vesicoureteral reflux was detected in 9 who underwent postoperative cystography. After becoming experienced and meticulously working with finer instruments in adults, rigid ureteroscopy can be a safe and efficient treatment for ureteral stones in every location in children.

Shock Wave Lithotripsy Causes Ipsilateral Renal Injury Remote From the Focal Point: The Role of Regional Vasoconstriction

Shock wave lithotripsy induced renal damage can occur as a result of multiple mechanisms, including small vessel injury and free radical production. Previous studies have demonstrated that shock wave lithotripsy exerts a regional change in renal hemodynamics, resulting in a global reduction in the glomerular filtration rate and renal plasma blood flow. We determined if biochemical evidence of cellular damage could be identified in ipsilateral locations remote from the shock wave site or in the contralateral kidney, suggesting regional or systemic alterations in renal function. Ten juvenile female swine underwent open insertion of microdialysis probes into the renal parenchyma at the right upper and lower poles, and left lower pole. The animals were divided evenly into a sham and a treatment group. Dialysate samples were collected from all 3 sites from the sham group at 10-minute intervals for 100 minutes and quantitatively assessed for conjugated dienes, a measure of lipid peroxidation and free-radical activity, signifying renal cellular damage. The animals in the treatment group underwent shock wave lithotripsy focused on the right lower pole. Dialysate samples were collected from all 3 sites at baseline and at 1,000 shock intervals for a total of 10,000 shocks and analyzed for conjugated dienes. The results from the sham and treatment groups as well as from the different locations within each group were compared using Student's t test. The mean conjugated diene ratio for the sham group was 3.59, 3.42 and 2.7 microM. for the right upper and lower poles, and left kidney (p >0.05). A dose related increase in conjugated diene ratio levels from the right lower pole (lithotripsy site) and to a lesser degree from the ipsilateral right upper pole were observed, which were significantly different from sham group measurements or the contralateral kidney of the treatment group (p <0.05). The elevation in conjugated diene levels at the lithotripsy site was also noted to be significantly greater than that of the upper pole of the ipsilateral kidney (p <0.05). The increase in free radical activity at a site remote from the treated region suggests detrimental global effects from shock wave lithotripsy therapy. These observations could be the result of vasoconstriction throughout the treated kidney with resultant ischemia-reperfusion injury. Although these global renal effects may subject patients with baseline renal dysfunction to irreversible renal damage, the clinical significance of our findings is unclear and warrants further investigation.

Apparatus for producing shock waves for technical, preferably medical applications

An apparatus produces intense pressure waves as shock waves for technical and preferably medical applications, especially for lithotripsy and/or pain therapy. Acoustic waves of high energy density are produced through the use of pressure pulsations. The pressure waves are produced by briefly heating a conductive electrolyte, whereby electric energy is converted directly and very largely without losses with the aid of an electric pulse for the purpose of heating up the electrolyte. The apparatus includes two electrodes which enclose the electrolyte and are controlled by a power pulse generator for outputting sound waves into a sound propagation medium.

Endoscopic treatment of pancreatic duct stones using a 10F pancreatoscope and electrohydraulic lithotripsy

Background: Endoscopic therapy with adjunctive extracorporeal shock wave lithotripsy fails to provide clearance of pancreatic duct stones in up to 25% of symptomatic patients. Direct contact lithotripsy may provide an additional option for removal of refractory stones. We report our initial experience using a prototype 10F “baby” endoscope to administer electrohydraulic lithotripsy. Methods: Five patients failing extracorporeal shock wave lithotripsy and one patient with recurrent pancreatic duct stones after surgery were selected to undergo endoscopic electrohydraulic lithotripsy. After pancreatic sphincterotomy and balloon dilation (8 or 10 mm), the 10F endoscope was introduced and electrohydraulic lithotripsy was used to fragment stones under direct visualization. Results: Six patients underwent 9 intraductal electrohydraulic lithotripsy procedures. Complete or partial pancreatic duct clearance was accomplished in all but one. No complications from the lithotripsy procedure were noted. The 5 patients with partial or complete duct clearance experienced complete relief of abdominal pain of at least 6 months’ duration following their final procedure. Conclusion: Electrohydraulic lithotripsy within the pancreatic duct provides an adjunctive endoscopic option for treatment of patients with symptomatic pancreatic duct stones. Our initial experience suggests that electrohydraulic lithotripsy therapy can successfully fragment stones refractory to conventional endoscopic stone extraction methods or extracorporeal shock wave lithotripsy. Further experience is necessary to establish the risks of electrohydraulic lithotripsy within the pancreatic duct.

The management of sialolithiasis in 2 children through use of extracorporeal shock wave lithotripsy

The management of salivary calculi in children may prove difficult for a number of reasons. Traditional investigations require ionizing radiation and in cases of sialography may be poorly tolerated. Similarly, any surgical treatment is likely to require general anesthesia and, in a number of cases, removal of the affected gland, which is associated with attendant risks. As an alternative, ultrasound and extracorporeal shock wave lithotripsy therapy offers low morbidity and outpatient procedures that are well tolerated, as illustrated by these 2 cases. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88: 44-9)

Shock wave effects in biomechanics

Focused shock waves convey energy from a source and deposit it in a localized region remote from the source. This mechanism is used to deliver crushing impulses to kidney stones in patients, but it may also be an undesirable source of tissue injury. Tissue injury occurs in extracorporeal shock wave lithotripsy (ESWL), a popular procedure used around the world to treat kidney stone disease. Shock waves can also be responsible for unexpected symptoms appearing remote from the site of blunt impact trauma. This paper describes two examples of the effects of focused shock waves on tissue. A victim of gunshot wound suffered specific neurological symptoms indicating highly localized injury to the spinal cord remote from the impact point and penetration of the missile. We suggest that wave focusing by thoracic vertebrae can concentrate energy into the spinal canal, with consequent injury to the spinal cord. Impulsive stress in repeated shock waves of order 20 MPa strength administered in ESWL is the mechanical stimulus of injury to the kidney. Research to increase the understanding of the causal relationship between the shock-induced mechanical stimulus and the consequent biomedical symptoms in the shock-wave treatment of kidney stone disease is described. The interaction of focusing shock waves with simple, planar polymeric membranes immersed in tissue-mimicking fluids has been studied. We have explored the nature of membrane failure in both cavitating and non-cavitating fluids. In water, thin nitrocellulose membranes are easily damaged during the passage of a lithotriptor shock wave by the collapse of proximal bubbles generated by cavitation. In uniform non-cavitating liquids, focusing shock waves do not by themselves cause damage, but after passing through tissue or simulated tissue, they do. Shocks with large amplitude and short-rise time (for example, in uniform media) cause no damage in non-cavitating fluids, while long-rise time, dispersed shock waves, though only moderately attenuated, do. A simple model of shearing at small scale provides a framework for accounting for the properties of the scattering medium and the membrane material in dynamic fatigue. The fact that the membranes exhibit fatigue-like behaviour suggests that a definition of dose can be formulated based on Miner’s Law. This definition gives the dose at failure in terms of the stress applied to the membrane by each shock wave and the failure stress. This analysis suggests that ESWL shock waves induce strain rates in tissue of order 10000 s−1 and that behind a tissue, phantom membranes fail after a dose of about 1400 effective shock waves, of the same order as the number of shock waves typically used in lithotripsy therapy and research. Above strain rates of about 40000 s−1, ESWL shocks cause virtually no damage.