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Background: The electrohydraulic high-frequency shock wave (Storz Medical, Taegerwilen, Switzerland) is a new way to create small fragments with frequencies up to 100 Hertz (Hz). This study evaluated the efficacy and safety of this method in a stone and porcine model., Materials and Methods: BEGO stones were put in a condom in a specifically designed fixture treated with different modulations to see stone comminution. Standardized ex vivo porcine model with perfused kidneys with 26 upper and lower poles of 15 kidneys was treated with the following modulations: voltage 16-24 kV, capacitor 12 nF and frequency up to 100 Hz. 2000-20,000 shock waves were applied to each pole. The kidneys were perfused with barium sulfate solution (BaSO4) and x-ray was performed to quantify the lesions using pixel volumetry., Results: There was no correlation between the number of shock waves and the powdering degree or the applied Energy and the grade of pulverization in the stone model. Regarding the perfused kidney model, the number of shock waves, applied voltage and frequency had no direct correlation with the occurrence of parenchymal lesions The detected lesions of the renal parenchyma were minimal, technical parameters had no significant impact and the lesions did not differ from the results of former experiments using 1-1.5 Hz in the same model., Conclusions: High-frequency shock wave lithotripsy can produce small stone fragments to pass in a very short time. The injury to the renal parenchyma is comparable to the results of the conventional SWL using 1-1.5 Hz., (© 2023. The Author(s).)

Urolithiasis is an urologist's daily business. This article provides an overview of the developments in the management of urinary stone disease since the 1970s. While conventional KUB X-rays and intravenous pyelography were standard imaging procedures in the past, computed tomography is the first choice today. Conservative treatments such as medical expulsive therapy were established to facilitate ureteral stone passage, but have come into discussion in the past few years. Fifty years ago, open stone surgery was the standard procedure to access renal stones. This has been superseded by minimally-invasive procedures ranging from percutaneous nephrolithotomy (PCNL) to extracorporeal shock-wave lithotripsy (ESWL) and ureteroscopy (URS), which is today's standard for most upper urinary tract stones. It would have been desirable if such enormous efforts and progress had been made in the evaluation of stone pathogenesis and the improvement of preventative measures. Unfortunately, the knowledge on stone formation has hardly improved compared to 1970., Competing Interests: Die Autoren geben an, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

Since the introduction of ESWL, PNL and URS during the early 1980s the application rate of ESWL has declined while those of PNL and URS have increased. This is mainly due to the facts that instruments and techniques for Intracorporeal Lithotripsy (IL) have made a continuous progress. This review shows that today an array of options for IL within the entire urinary tract is available to treat stones in a perfect minimal invasive way. At the same time further improvements of IL are already visible.

The rising prevalence of kidney stone disease is associated with significant costs to healthcare systems worldwide. This is in part due to direct procedural and medical management costs, as well as indirect costs to health systems, patients, and families. A number of manuscripts evaulating the economics of stone disease have been published since the 2008s International Consultation on Stone Disease. These highlight costs associated with stone disease, including acute management, surgical management, and medical management. This work hopes to highlight optimization in care by reducing inefficient treatments and maximizing cost-efficient preventative strategies.

Unlabelled: There has been controversy over whether extracorporeal shock wave lithotripsy (ESWL) can cause damage to the endocrine cells of the pancreas, leading to the later development of diabetes mellitus. Authors from Germany prospectively evaluated acute endocrine pancreatic injury as collateral damage caused by the ESWL for treating upper urinary tract stones. In a careful study they showed that there was no effect on serum levels of variables indicating exocrine and endocrine pancreatic tissue damage, suggesting that the idea that ESWL might lead to future diabetes mellitus is unlikely to be correct., Objective: To detect acute damage to pancreatic cells by extracorporeal shock wave lithotripsy (ESWL), with a focus on endocrine function, as recently the development of diabetes mellitus has been suggested to be a late complication of treatment of upper urinary tract stones, and injury to pancreatic tissue by ESWL, leading to insufficient endocrine function, has been proposed as an explanation of this effect., Patients and Methods: The study included 12 consecutive patients treated with ESWL for proximal ureteric or kidney stones, using a third-generation electromagnetic lithotripter. To evaluate pancreatic tissue injury caused by ESWL we determined blood variables known to indicate exocrine and endocrine pancreatic cell damage; blood samples were taken before, during, immediately after, and 1 h and 24 h after ESWL to determine the serum levels of amylase, lipase, insulin, glucose, c-peptide and glucagon. Eight patients treated with ESWL for distal ureteric stones were evaluated in the same way and served as the control group., Results: Neither the variables indicating islet cell damage (c-peptide, insulin and glucagon), nor those indicating damage of exocrine pancreatic cells (amylase and lipase) changed significantly over the time course in both groups., Conclusion: We could detect no immediate effect on the serum levels of variables indicating exocrine or endocrine pancreatic tissue damage caused by ESWL for urinary tract stones. The hypothesis that ESWL leads to pancreatic trauma with consecutive development of diabetes mellitus therefore seems unlikely.

Storz Medical AG (Kreutzlingen/Switzerland) has developed a new electromagnetic shockwave (SW) generator, the "SLX-F2", which allows the user to choose between a small-focus, high-pressure treatment regime or a wide-focus, low-pressure option. The aim of this study was to investigate, under standardized conditions, the impact of these two different treatment regimes on SW-induced renal injury. SW-induced renal injury was investigated by using the standardized model of the perfused ex vivo kidney. SWs were applied under ultrasound control in the parenchyma of a kidney pole. Different SW numbers (20, 50, 125, 250, 500, 1,000) were applied in three groups: group A was treated with a wider focus (80 MPa), groups B (60 MPa) and C (120 MPa) with a smaller focus (each parameter setting was repeated ten-fold). Disintegration capacity (measured by crater volume in cubes of plaster of Paris) was the same in groups A and C. After SW exposure, barium sulphate suspension was perfused through the renal artery. The maximum diameter (mm) of the extravasation in the cortex, representing the extent of vascular injury, was measured on X-ray mammography films. H&E staining was performed. In all three groups (A, B, C) a higher number of SWs caused the diameter of the extravasate to increase, with statistical significance appearing at 1,000 shots versus 20 shots (p < 0.05). Vascular injury was not influenced by the focal size and positive peak pressure at identical SW numbers applied. Histology of the focal area showed gap-like defects. Our ex vivo data show that renal vascular injury is independent of the focal diameter of the SW generator at the same peak positive pressure and disintegration power. This confirms the in vivo findings that show renal injury caused by SW as being related to the number of SWs administered. Clinical studies are needed to investigate whether there is any advantage to offering both treatment regimes in one SW machine-for example, by using the "wide-focus, low-pressure" option for kidney stones and the "small-focus, high-pressure" regimen for stones in the ureter. The renal injury caused by either regime remains comparable.

We performed a prospective, non-randomised study to determine the appropriate first-line treatment modality for distal ureteral stones. Between 2003 and 2004, a total of 124 patients with distal ureteral calculi were entered into the study (mean age 48 years, 35 women and 99 men). Sixty-two patients were treated with shock wave lithotripsy (SWL) and 62 patients with ureteroscopy (URS). The average stone size was 6.9 mm (3-33 mm) for SWL and 7.2 mm (3-30 mm) for URS. The treatment decision depended on the patients' preference and clinical parameters (i.e. contraindications for anaesthesia). URS was performed under general anaesthesia, using semirigid 8 Fr instruments. SWL was performed under analgo-sedation using a Modulith SLX. Of patients treated with SWL, 84% had a treatment success within 7 days, 98% after URS. These results show a significant success (P=0.005) in favour of URS. The average in-patient stay after SWL was 3 days and for URS 4 days (not significant). The results show a high efficacy and a low complication rate for both modalities. The attained stone-free rate shows a significant advantage for primary URS.

Objectives: After SWL treatment, many patients have residual fragments in the kidney or ureter. Fragments 2 stones episodes. These patients and their referring urologist received follow-up questionnaires which contained questions about stone clearance, late complications, auxillary measures and dietary or drug metaphylaxis., Results: Most residual stone fragments were located within the lower calyx (17%) and the renal pyelon (14%). Stone analysis was available in 142 patients with CIRF and revealed calciumoxalate calculi in 93.6% of the cases. In 78.6%, CIRF cleared spontaneously within few weeks and did not recur within 5 years. However, residual stones led to stone recurrence and need of re-treatment in 21.4%. Renal pyelon (23%) and calices showed comparable growth of former CIRF (lower calices 26.5%, middle calices 27%, upper calices 26%). Only 48% of the patients with recurrent stone formation followed dietary metaphylaxis. However, a significant correlation between a general or specific metaphylaxis and stone growth of CIRF could not be demonstrated., Conclusions: Most of the CIRF after SWL pass spontaneously without any complications. But considering that one fifth of the patients developed new stones at the side of residual fragments, it is obvious that close follow-up is required. Although we could not demonstrate a relation between metaphylaxis and stone re-growth, it is conceivable that adequate metaphylaxis can reduce stone recurrences.

More than 30 % of all admissions to an urologic clinic are for the treatment of urinary stones. In almost all cases, the treatment is minimally invasive employing extracorporeal shock wave lithotripsy (ESWL), ureterorenoscopy (URS) or percutaneous nephrolithotomy (PCNL). Technical advances in endourology and a growing expertise in ESWL led to a decline in ESWL and an increase in endoscopic techniques. In comparison with ESWL, the endoscopic techniques are more invasive but in most cases achieve a stone free state faster. With the introduction of diagnosis related groups (DRG), the economic aspect of stone therapy is gaining in importance. Stone prevention leads to a cost reduction in the health care system, justifying the use of an appropriate stone metaphylaxis. This review article presents the current recommendations for interventional urinary stone therapy and lists the options of conducting both medical and economically rational therapy.

Open surgery was the standard therapy for urinary calculi up to about 30 years ago. This changed upon introduction of extracorporeal shockwave lithotripsy (ESWL) in 1980, a procedure that is now the primary therapy for 70 % of the patients in western countries. Simultaneously, endourological procedures like ureterorenoscopy (URS) and percutaneous nephrolithotripsy (PCNL) have been improved, and now, modern small diameter and highly efficient instruments offer an ideal alternative to shockwave lithotripsy. Today, minimally-invasive stone treatment has replaced open stone surgery almost completely. This article introduces ESWL, URS and PCNL and discusses indications, outcomes and limitations.

Background and Purpose: The architecture of the lower renal pole seems to have a considerable influence on caliceal stone clearance after different therapeutic modalities. The published data are partially inconsistent, and publications on reproducibility are completely lacking. The aim of this study was to evaluate the intraobserver and interobserver reproducibility of different measures of lower-calix anatomy., Materials and Methods: We studied the intraobserver and interobserver reproducibility of parameters describing the lower-pole anatomy that are significant for treatment outcome. Forty renal units without urologic disease were analyzed by five independent urologists. Infundibular length (IL), infundibular width (IW), and lower infundibulopelvic angles (LIP) were measured by the Elbahnasy (LIP I), Keeley (LIP II), and Gupta (LIP III and LIP IV) methods. Statistical analysis of each parameter and investigator was performed., Results: All LIP angles showed low interobserver correspondence: correlation coefficients (CC) did not exceed 0.44 (P < 0.05). Even the relatively clearly defined parameters IW and IL achieved CCs of only 0.63 and 0.49, respectively. The intraobserver correlation achieved better results: 0.73 (LIP I), 0.84 (LIP II), 0.73 (LIP III), 0.65 (LIP IV), 0.88 (IL), and 0.82 (IW). With the Elbahnasy method, almost all renal units were classified as favorable for stone persistence after shockwave lithotripsy. With the Keeley and Gupta methods, more than 50% of the kidneys were defined as having low clearance probability., Conclusions: Assessment of the chosen parameters is difficult and shows high interobserver variation. Inexperience in measuring the specific angles and low imaging quality can limit correct evaluation. The large number of kidneys with anatomy inappropriate for clearance of lower-pole stones may explain the poor outcome of shockwave treatment for stones in a lower calix. Prospective studies will determine the clinical value of anatomic assessments.

With a prevalence of around 5% in western countries, urolithiasis is a frequently occurring disease but with a poorly understood pathogenesis. Effective prevention is not possible for most stone types, in particular for calcium-containing stones, which occur most frequently. Additionally, after occurrence, patient compliance is often inadequate. Interventional therapy becomes necessary after stone manifestation within the urinary tract. Not all stone compositions respond to a drug treatment. Whereas in the seventies, stone treatment meant open surgery newly developed minimally-invasive procedures have displaced this treatment. The clinical introduction of extracorporal shock wave lithotripsy (ESWL) has played a crucial role in this process. Today, more than 80% of all urinary stones can be treated by modern lithotripters. Combination with other minimally-invasive procedures further improve stone free rate. This article provides an overview of technique, application and results of ESWL treatment.

Background and Purpose: Very few reports have been published on the management of Peyronie's disease by shockwave therapy. Existing publications on this topic are based on subjective improvement described by the patients themselves. Our aim was to determine objectively the effect of shockwave therapy on the signs and symptoms caused by Peyronie's disease., Patients and Methods: To date, 65 patients (age 58.4 +/- 8.7 years) have been enrolled in a therapeutic pilot study. The disease duration was 33.7 +/- 42.9 months. Inclusion criteria were palpable plaque together with deviation, pain (visual pain scale), or loss of distal rigidity. Clinical examination (prior to first therapy and 1, 6, and 18 months after last shockwave delivery) included palpation and sonography of the plaque (mean surface size 2.2 +/- 1.1 cm(2)), measurement of deviation, assessment of pain and distal loss of rigidity (artificial erection induced by intracavernosal injection of 5 microg of alprostadil [Caverject]). Shockwaves (1,000 impulses at 12 kV per square centimeter of plaque) were delivered to the nonerect penis once a week for a period of 5 weeks with the Minilith; Storz Medical., Results: Eighteen months (N = 35) after the last shockwave session, the deviation angle had decreased from 59.3 degrees +/- 38.1 degrees to 49.3 degrees +/- 32.5 degrees (N = 24; P = 0.1496). Pain during erection disappeared in 15 of 17 patients and was reduced in 1 other patient (P < 0.0001). There was no effect on distal rigidity in any patient. Six patients achieved satisfactory sexual intercourse (vaginal penetration) before and 15 patients after shockwave therapy. The adverse effects were small skin hematomas in 90% of patients and initial transient macrohematuria in 30%., Conclusion: Our study demonstrates objective and subjective changes in patients with Peyronie's disease after shockwave therapy. Artificial erection served as a control to assess improvement of the deviation angle.

Although ESWL allows for the treatment of most urinary stones, there are remaining situations, in which satisfying results cannot be achieved, e.g. large kidney stones or specific anatomy. In such cases endoscopic procedure like ureterorenoscopy (URS) or percutaneous nephrolithotomy (PCNL), alone or in combination with ESWL, allow minimally-invasive removal of these stones. Primarily, the development of modern intracorporeal lithotripter probes and extraction instruments along with a reduction of instruments' diameter could improve efficacy and reduce mortality. This article will provide an overview of techniques, application and results of endoscopic urinary stone treatment.

The 7.5 and 9.0 F flexible ureterorenoscopes are used widely in endourology. These scopes, along with new available tools and probes, enable intrarenal ureteroscopic access to renal stones in the lower pole. Following individual clinical experiences the infundibulopelvic angle has to be respected for the selection of different scopes, tools and probes. The aim of this study was to determine the influence of different scopes, tools and probes on the angle of the active and passive flexion of the flexible ureterorenoscope. The angles of the active and passive flexion and maximum irrigation flow of different flexible ureterorenoscope (9.0 F Wolf, 7.5 F Olympus, 7.5 F Storz) were measured repeatedly in vitro using nine different inserted tools and/or probes. In addition, the maximum allowing for easy passage of the nine different tools/probes through the channel of the scope were measured. The Olympus scope without working instrument present, allows for the greatest deflection. The flexible Lithoclast, the non-nitinol baskets, and the 365 microns laser probes significantly inhibit the deflection of all scopes. The greatest deflection with inserted working tool was possible using the Wolf and Storz scopes. Both nitinol tools as well as the 200 microns laser probe had only minimal influence on the deflection. The 200 microns laser probe reduces the irrigation flow from 50 to 28 ml/min. In contrast, the baskets reduce the irrigation flow from 50 to 2 ml/min. There are significant differences of the active and passive flexion depending on the ureterorenoscopes itself and the different tools. In order to perform a successful flexible ureterorenoscopic stone treatment in the lower pole, the inhibition of the flexion of the different scopes together with the individual infundibulopelvic angle must be respected when selecting different tools and probes.

Objectives: A project was initiated by the Health Care Office of the European Association of Urology in order to formulate common recommendations and guidelines for the treatment of patients with urolithiasis. The basic task for the working group therefore was to extract and evaluate evidence from the literature in order to reach a consensus on how these patients could best be managed., Methods: Extensive reviews of the literature together with a thorough and detailed discussion of the various topics, by a working group including of experts from several European countries, provided the basis for a consensus overview of urolithiasis and its management., Results and Conclusions: Recommendations are given for the management of patients with acute stone colic and for active removal of stones from the ureter and kidney. Moreover, the principles for risk evaluation of patients with recurrent stone formation and appropriate recurrence preventive treatment are given.

Purpose: To elucidate the frequency and adversity of the effects of shockwave lithotripsy (SWL) on the male reproductive system. We investigated the possible alterations in the quality of semen in patients treated by SWL for pelvic ureteral stones., Patients and Methods: The semen of 10 men was examined 1 day before and 5 and 90 days after SWL for distal ureteral stones, in accordance with the World Health Organisation guidelines. The results were compared with those from the semen samples of 10 healthy male volunteers undergoing SWL for calculi of the upper urinary tract., Results: Microscopic analysis of the semen samples revealed a transient decline in sperm density (24.7%), sperm motility (10%), sperm vitality (8%), and seminal fructose (27.5%) after SWL for distal ureteral stones. A distinctly higher number of spermatozoa of pathological origin was detected after SWL in the same group. There was no trace of microscopic hemospermia before shockwave treatment, but it was detected in 90% of the patients with lower ureteral calculi after SWL. Macroscopic hemospermia was detected in two of these nine patients. No deterioration of the semen characteristics and no hemospermia was observed after treatment in the control group with upper urinary stones., Conclusions: Our investigations confirmed a transient deterioration in semen quality after SWL for distal ureteral calculi, whereas no deterioration was observed after SWL for upper ureteral stones. Impaired sperm quality values returned to normal within 12 weeks after SWL, clearly indicating a damaging effect of SWL on seminal vesicle or ejaculatory duct function. The initial procreative capacity was restored in all patients.

Objective: To determine the efficacy of ESWL treatment in children and the need for auxiliary urological procedures. In a retrospective analysis we investigated the number of auxiliary procedures and the stone-free rate in children after ESWL treatment., Methods: 28 girls and 21 boys with a total of 56 stones were treated from January 1990 to January 1999. ESWL was carried out on either the Lithostar Plus or the Modulith SL20/SLX. Auxiliary procedures were subdivided into curative (ureterorenoscopy, percutaneous nephrolitholapaxy) and adjuvant (urethral stent, nephrostomy)., Results: 34.7% of the children were stone-free after the first ESWL treatment; 40.8% of the children were discharged with residual stone particles ready for spontaneous passage; 24.5% underwent re-ESWL treatment. Auxiliary urological procedures were required in 28.6% of the cases (adjuvant 18.3%, curative 10.3%)., Conclusions: Extracorporeal shock wave lithotripsy is also a highly effective method of treatment for urolithiasis in children. However, curative or adjuvant auxiliary urological measures are required. In order to achieve high success rates, it is advisable to perform this method of treatment in centers with broad experience in ESWL and endourological procedures in children.

Despite the development of extracorporeal shockwave lithotripsy, endoscopic stone removal, with or without intracorporeal lithotripsy, is still an effective minimally invasive alternative for special indications. There is no defined all-purpose lithotripsy procedure for contact lithotripsy. The choice of the lithotripsy procedure for endoscopic stone disintegration depends on a number of different factors, the main one being stone localization. Small calibre, flexible probes (electrohydraulic, pneumatic, laser) are especially appropriate for ureterorenoscopy, but the speed of stone disintegration is a limiting factor. In contrast, large calibre rigid probes (ultrasound) are clearly more effective, but are unsuitable in size for flexible ureterorenoscopy. This indicates that the type and size of the endoscope decisively influences the choice of devices for endoscopic stone disintegration. Additional inhibiting factors are the flexibility or the rigidity of the instrument and the diameter of the working channel. It must be noted that total costs are not only calculated on the purchase of the equipment, but must also cover disposable materials.

Objective: Additional anesthesia is required to minimize the tolerable pain level in efficiently performed extracorporeal shockwave lithotripsy (ESWL) with electrohydraulic and electromagnetic sources. In order to assess optimum anesthesia for each patient undergoing a standardized ESWL protocol, pain measurement and scoring were carried out. We attempted to determine the individual type and amount of analgesia prior to treatment., Methods: Patients (n = 95) with urolithiasis underwent pain measurement and scoring prior to ESWL. 'Threshold of pain' (TP) and 'maximal tolerable pain (MTP) were assessed by inducing ischemia pain with the submaximum effort tourniquet technique. Pain intensity was assessed by a verbal rating scale (VRS). The results of pain measurement and amount of analgosedation were correlated in two phases. Patients were administered an oral premedication of 0.1 mg/kg midazolam. Phase 1: 60 patients were randomized into three groups: (1) piritramide (0.1-0.3 mg/kg) and midazolam (1-3 mg) i.v. (2) Lidocaine/prilocaine cream topically (30 g) to skin and diclofenac supp. 100 mg. (3) No analgesia. Phase 2: Based on the data of phase 1, cut-off points for TP and MTP were set for female and male patients. In accordance with these results, 35 patients comprised group 1 for anesthesia with piritramide/midazolam, group 2 with lidocaine/prilocaine cream and diclofenac supp. and group 3 for no analgesia at all. The electromagnetic shockwave sources Modulith SLX and Lithostar Plus were utilized., Results: Phase 1: All patients randomized for group 1 (intravenous analgosedation) were treated in accordance with the protocol. 65% of group 2 (cream/suppository) tolerated treatment as planned. 35% of patients selected for ESWL without analgesia (group 3) remained within this group. Patients requiring additional analgosedation displayed lower TP and MTP. The cut-off points for females and males were TP >/=25/35 s and MTP >/=45/60 s, respectively. Phase 2: 20/35 patients were preselected for a nonintravenous protocol. Five out of these 20 violated the protocol. The rate of additionally administered analgesia was lower than in phase 1: 35:10% in group 2 (cream/supp.), 65:40% in group 3 (no analgesia)., Conclusions: The TP and MTP levels are lower in patients requiring stronger analgesia. The determined parameters are suitable for patient preselection and individual assessment of anesthesia prior to ESWL. It may be assumed that 50% of patients administered intravenous opioids are overtreated. Routine pain measurement for patient depends on the individual pain tolerance level. A third phase of this study recruiting a large number of patients will contribute to the confirmation of these results.

At the doorstep of the twenty-first century the role of extracorporeal shock-wave lithotripsy (ESWL) as the treatment of choice for more than 80% of all stones in children is established. ESWL is safe and effective, with very few differences in success rates being observed among different lithotriptors. The present problem with ESWL appears to be the residual stone fragment, which has a proven clinical significance. A thorough metabolic evaluation and metaphylaxis is indicated in all children, and this will enable physicians to deal with the residual fragments in a more cause-specific manner and prevent regrowth. Another subject that needs prospective randomized studies to be unveiled is the assumption that a specific or universal metaphylaxis, possibly with alkaline citrates, will enhance stone clearance, lower the incidence of residual stone fragments, and optimize the ESWL results. Finally, both percutaneous nephrolithotomy and ureteroscopic stone removal have been established in children as safe and effective treatment options. This gives the clinician the opportunity to choose from a wide range of treatment alternatives, including open surgery, and only this approach will ensure 100% stone removal in individual patients along with the prevention of recurrence and, thus, the elimination of long-term morbidities in this vulnerable patient population.

The Modulith SL 20* was designed as a third generation lithotriptor with outstanding disintegrative efficacy in vitro, and equipped with a combined fluoroscopic and ultrasound localization system integrated in a multifunctional table. Its introduction to clinical extracorporeal shock wave lithotripsy took place in 3 phases. In phase 1 (49 patients) only in line ultrasound localization was possible. The many caliceal stones were adequately disintegrated with restricted generator voltage. In phase 2 (81 patients) fluoroscopic localization with the virtual focus of an adapted x-ray C-arm unit enabled in situ lithotripsy of ureteral stones in 33% of all patients. Phase 3 (549 patients) was characterized by additionally increasing the generator voltage to 20 kv. This development of the lithotriptor by improving the localization system and shock wave energy resulted in the possibility for successful disintegration of stones in the entire upper urinary tract (including the complete ureter), decreased treatment time (52 to 39 minutes) and an improved efficiency quotient (0.45 to 0.67). During phase 3 auxiliary measures were performed before lithotripsy in 24% of the cases. After 1.8% of the treatments minor or moderate perirenal fluid collection or bleeding was detected by routine followup sonography. A 91% stone-free rate was achieved with only 9.3% curative auxiliary measures after extracorporeal shock wave lithotripsy, including a 23% retreatment rate. Thus, the Modulith device had a high efficacy quotient compared with other lithotriptors.

The aim of this investigation was the development of an easily reproducible model with which to evaluate shockwave-induced renal tissue damage using light and electron microscopy. Kidneys (n = 45) from freshly slaughtered pigs were perfused under physiologic conditions and treated with shockwaves at different doses (2-250 shockwaves; 12-20 kV) on the Modulith SL 20 lithotripter. The dose-dependent alterations in tissue structure were characterized by disintegration of tubular cells leading to circumscribed gap-like defects resulting from reticular fiber disruptions. Even after low shockwave doses, cellular and subcellular alterations could be observed. Our findings in this ex vivo model verify the development of considerable strictly localized, dose-dependent shockwave-induced damage of the renal parenchyma. On morphologic grounds, we cannot confirm a primary lesion or rupture of blood vessel walls as the cause of the shockwave lesions. The destruction of tubular cells in combination with disruption of peritubular and pericapillary reticular fiber coats results in capillarotubular leaks, which can explain even severe transitory macrohematuria after clinical shockwave lithotripsy without renal hematoma formation.

Little is known about the mechanisms and determining factors of shock wave-induced kidney trauma. After classification of the renal lesion in a canine model, we attempted to establish an ex vivo model using the isolated kidney of the pig perfused by Tyrode's solution under physiologic conditions. After shock wave application on the Modulith SL 20, vessel lesions were evaluated by microangiography to determine the size and frequency of dye extravasation in the different areas of the organ. Variation of the focus localization caused different patterns of lesions that characterized the pathway of the shock wave. In particular, constant petechial extravasation in the cortex was observed. The generator voltage correlated with the diameter and the frequency of the lesion area. The number of shock waves primarily affected the incidence of vessel rupture in the regions adjacent to the focal zone. Light microscopy revealed dose-dependent necrosis of tubular cells up to gap-like parenchymal defects. Even after application of the minimal shock wave doses, electron microscopy demonstrated vacuolization of tubular cells in the shock wave focus. Traumatic junctions between capillaries and the tubulur system can explain clinically observed macrohematuria without renal hematomas. With this model, it was possible to evaluate localization and dose dependence of shock wave-induced kidney trauma with high sensitivity and reproducibility. Further advantages of the model were easy availability and the fact that studies on living animals were not necessary. Therefore, standardization and comparison of different lithotripters becomes possible.

The treatment of ureteric calculi by extra-corporeal shock waves was found to have an 80% success rate by Mannheim authors, regardless of the site of the calculus. The authors compared two 3rd generation apparatuses: 1--the Siemens Lithostar Plus, in which waves are produced by a electromagnetic cylinder and focussed by a parabolic electromagnetic cylinder and focussed by a parabolic reflector: 2--the Storz Medical Modulith SL 10, in which waves produced by an electromagnetic coil are focussed by acoustic lenses. Both apparatuses are based upon image-intensification and ultrasonography concepts. No difference in efficacy was found between the two apparatuses. A second shock wave session was necessary in 16% of cases and some other type of additional treatment in 7% of cases.

With extracorporeal shock wave lithotripsy, stone fragmentation and the potential creation of residual stones has become an integral part of the treatment strategy. Therefore, true recurrence, regrowth and pseudo-recurrence determine the rate of new stone formation. In nonselected series the overall recurrence rate after ESWL varies between 6% after 1 year and 20% after 4 years. The comparison between recurrence rate after ESWL and the natural recurrence rate reveals that the results of ESWL are better than expected. Lithotripsy has no specific effect on true stone recurrence, and even the pseudo-recurrence is of minor clinical significance. Nevertheless, metaphylaxis keeps its place in treatment of recurrent urolithiasis.

Extracorporeally-perfused rabbit kidneys were exposed to five shock waves at 14 kV on the XL1 Dornier experimental lithotripter (Dornier Medical Systems, Inc., Germering, Germany). While the perfusion flow rate was kept constant, the arterial perfusion pressure was recorded to assess changes in vascular resistance. Immediately after shock wave application, perfusion pressure decreased by 20%-30%, followed by a short, relative pressure rise that did not reach pretreatment values. Fifteen-twenty minutes later, arterial perfusion pressure reattained pretreatment values. Subsequent to treatment, urine flow decreased by greater than 50%. The observed pressure rise was also induced in nontreated kidneys by perfusion with the effluent of treated kidneys indicating that this is based on a humoral mechanism. On the other hand, shock wave application to formalin fixed kidneys only caused a marked decrease in arterial perfusion pressure, suggesting that this effect is due to a pure mechanical interaction of the shock wave also found with denaturated kidneys. The observed decrease of urine flow is probably caused by a decreased filtration rate. Since this was not the case in nontreated kidneys being perfused with the effluent of treated kidneys, the reduction of urine flow after extracorporeal shock wave lithotripsy does not appear to be mediated by a humoral factor, but is more likely a result of the mechanically-induced vasodilation with consecutive decline of the glomerular filtration rate.

With extracorporeal shockwave lithotripsy (ESWL) stone fragmentation and the potential creation of residual stones has become an integral part of the treatment strategy. Therefore true recurrence, regrowth and pseudo-recurrence determine the rate of new stone formation. In unselected series the overall recurrence rate after ESWL varies between 6% after 1 year and 20% after 4 years. The comparison between the recurrence rate after ESWL and the natural recurrence rate reveals that the results of ESWL are better than expected. Lithotripsy has no special effect on true stone recurrence, and even pseudo-recurrence is of minor clinical significance.

A third generation lithotripter was developed incorporating the advantages of high disintegrative efficacy, anaesthesia-free treatment, combined sonographic and fluoroscopic localization system as well as a multifunctional table for interdisciplinary use. The shock wave generator consists of a cylindrical-shaped electromagnetic coil with a paraboloid reflector. The waves are coupled by means of a water cushion and an impedance adapted foil in which the patient is comfortably positioned. Stones are localized by an in-line ultrasound probe or fluoroscopically by the integrated C-arm. Preclinical trials using the in-vitro stone model demonstrated the superior disintegrative capacity. The in-vivo animal studies evaluated the dose-dependent and reversible kidney trauma, which was comparable to that induced by other lithotripters. The clinical evaluation of the Modulith SL since 1988 was divided into three phases with different technical equipment. It was indicated that sonographic stone localization enables treatment of nearly all kidney stones and 12% of the ureteric calculi. As preference was given to in situ disintegration of all ureteral stones, X-ray targeting became necessary. By increasing the generator voltage in the third phase together with advanced experience, the disintegration rate (94%) was improved. The number of auxiliary measures after ESWL (11%) and treatment time (average 39 min) was decreased. Eighty-eight percent of our patients were stone-free at follow-up. The experience demonstrated that this lithotripter is also easy to handle for gallbladder stones and highly effective (82%) in treatment of endoscopically non-extractable bile duct stones.

Using the new electromagnetic shockwave source of the Modulith SL 20 shockwave-induced renal trauma was evaluated by acute and chronic studies in the the canine kidney model. In a further study the electromagnetic shockwave source of the Lithostar Plus Overhead module was tested. Overall, 92 kidneys were exposed to shock waves coupled either by water bath (Modulith lab type) or by water cushion (Modulith prototype, Lithostar Overhead) under ultrasound localization. The generator voltage ranged between 11 and 21 kV, the number of impulses between 25 and 2500. After application of 1500/2500 shocks the extent of the renal lesion depended strictly on the applied generator voltage and was classified into 4 grades: Grade 0, no macroscopic trauma detectable (at 11-12 kV); grade 1, petechial medullary bleeding (at 13 kV); grade 2, cortical hematoma (at 14-16 kV); and grade 3, perirenal hematoma (17-20 kV). Whereas at low and medium energy levels the number of shocks played only a minor role, at maximal generator voltage (20 kV) even 25 impulses induced a grade 2 and 600 shocks a grade 3 lesion, emphasizing the importance of shockwave limitation in the upper energy range. In shockwave-induced renal trauma a vascular lesion was predominant and cellular necrosis was secondary. Coupling with a water cushion resulted in a 15%-20% decrease in the disintegrative and traumatic effect, which was compensated for by increasing the generator voltage by 2 kV. Long-term studies showed complete restitution following grade 1 and 2 trauma, whereas after a grade 3 lesion a small segmental and capsular fibrosis without hyperplasia of the juxtaglomerular apparatus was observed. Based on the characteristic ultrasound pattern found in the first study, the threshold for induction of grade 1 lesion was investigated. With both lithotripters a wide range for induction of a grade 1 lesion (Modulith 234-411, Lithostar Plus 220-740) and also a significant overlapping with grade 0 and 2 lesions was seen at low energy settings (levels 2-4). In contrast, the range of shocks (Modulith 96-150, Lithostar Plus 90-142) and overlapping was minimal when high energy was used (levels 7-9). Finally, the disintegration-trauma coefficient combining the results obtained in a standard stone model with those of the canine kidney model was introduced.

A series of 138 patients with ureteric calculi was treated by in situ extracorporeal shock wave lithotripsy (ESWL) during the clinical introduction of the Modulith SL 20. This machine represents a newly developed lithotriptor with an electromagnetic cylinder as shock wave source and a dual localisation system consisting of in-line ultrasound and an integrated fluoroscope C-arm. During the first 2 months, 12 patients (phase 1) were treated under ultrasound localisation alone; during the next 5 months, 37 patients (phase 2) were treated using dual imaging modalities with reduced peak pressure (max. 18 kV = 800 bar); during the final 7 months, 89 patients (phase 3) were treated under ultrasonic and fluoroscopic localisation combined with an increased maximal shock wave pressure (20 kV = 1024 bar). The introduction of fluoroscopic targeting (phases 2 and 3) resulted in satisfactory localisation of calculi in the mid-ureter, previously limited by use of only coaxial ultrasound. The extension of stone localisation to the whole length of the ureter was associated with a marked decrease in treatment time, reflecting the easy handling of the dual localisation system. The rise in generator voltage (phase 3) improved the disintegration rate from 81% (phase 2) to 85%, whereas the number of impulses remained unchanged. However, the rate of auxiliary procedures following ESWL (adjuvant and curative) was reduced from 33% (phase 2) to 24.5%. Thus the Modulith SL 20 in its final design enables in situ ESWL to be the treatment of choice for all ureteric calculi, rendering special positioning techniques or multiple treatment unnecessary.

Endoscopic treatment of bile duct stones is currently successful in 86% of patients. We prospectively studied the efficacy and complication rate of extracorporeal shock-wave lithotripsy (ESWL) of problematic bile duct stones combined with endoscopy. When stone removal was not possible, patients were subjected to ESWL. Fragmented stones were removed endoscopically. During 1 year, 220 patients presenting with choledocholithiasis were diagnosed and 188 were successfully treated endoscopically. In all, 3 subjects received alternative treatment and the remaining 29 (13%) constituted our study group; 19 (65%) were women and the mean age was 76.7 years. Overall, 22 (76%) were high-risk patients; 23 (79%) were jaundiced and 9 (31%) had cholangitis at admission. The most frequent indication for ESWL was stone size. Stone fragmentation was achieved in 80% of cases. Complications were mild and were managed conservatively. No patient died. Complete stone clearance was possible in 23 (80%) cases. The association of ESWL and endoscopy enhanced the success rate of endoscopic stone clearance from 86% to 96%. During the same period, open surgery was performed in 4 cases for residual common bile duct (CBD) stones and in 32 cases in association with simultaneous cholecystectomy.

In the present study, the authors analyze the radical change in the treatment of complex renal lithiasis. They advocate the use of this combined approach in patients with a large stone mass or those with obstructive problems of the urinary tract. They discuss the contraindications of this technique; i.e., pelvic kidney, septic urinary infections and severe cardiopulmonary disease. From 1983 to June 1988, a total of 5,657 stone patients were treated at their department; 921 were treated by PCNL combined with ESWL. In 92% of the cases, PCNL was successful in removing most of the stone mass. The complications encountered were fever, hemorrhage, colon perforation, stenosis of UPJ post-PCNL and intrathoracic extravasation. Nephrectomy was warranted in 2 cases due to complication.

More than 20 second-generation lithotriptors have been introduced for extracorporeal shock-wave lithotripsy. Despite great technical progress, each machine still has its specific short-comings. In cooperation, Storz Medical (Kreuzlingen, Switzerland) and the Department of Urology (Klinikum Mannheim, FRG), have developed a new lithotriptor designed to overcome these drawbacks. Energy source: Electromagnetic cylinder with paraboloid reflector (40 cm) for focusing, providing a wide range of pressure (190-1,000 bar) and a focal zone of 28 x 6 mm. The focal depth is maximally 15 cm. Coupling and positioning: Water cushion with patient lying on a specially designed 'acoustic cradle' consisting of an impedance-adapted foil. This is integrated in either a manually or automatically operated table. Localization: Coaxial ultrasound probe for real-time scanning and integrated C arm with pulsed fluoroscopy using a virtual focus (moved along x-axis) for stone localization. In 1989, we commenced with the first treatment based on our own in vitro and in vivo studies to determine the range of energy required for safe application. We treated 137 stones (100 caliceal, 19 pelvic and 18 ureteral) in 88 patients. The mean generator voltage was 16 kV (10-18 kV). Successful disintegration was achieved in 83 patients (95%) employing an average of 2,359 impulses (940-3,500). Thirteen percent of the treatments were performed without any anesthesia on lower generator voltage (10-15 kV), whereas the majority of calculi were treated under intravenous analgesia. The 5 failure cases included 2 stones in a caliceal diverticulum. Moreover, 12 patients with biliary calculi (11 gallstones and 1 bile duct stone) were successfully treated; 1 of these cases required a second treatment session.

Second generation local shockwave lithotripsy appliances (Lithostar) were used for the treatment of upper and lower ureteral stones in 199 patients, 145 of whom had upper ureteral stones. In 78 patients the calculi were pushed back and all but one disintegrated. In 33 patients a catheter was inserted past the stone, which resulted of primary disintegration in 66%. In 19 of 34 patients (56%) in whom the stones could not be moved, primary disintegration was achieved. Distal ureteral stones were present in 54 patients and these were treated successfully by ESWL alone in 83.3%. Auxiliary measures (total 10%) included ureteroscopy, percutaneous extraction and ureterolithotomy. The results are discussed under the aspects of 'in situ' versus 'push-and-smash' procedures.

Extracorporeal shock wave lithotripsy has been clinically successful for more than 5 years. Currently, several devices commonly termed second generation lithotriptors are under experimental or clinical trials. We present a prototype multifunctional urological table that uses a new mode of shock wave generation along with local coupling to the patient. The results of the first 400 treatments are presented after a brief description of pre-clinical experiments. The prototype has been in operation since March 1986. Particular attention is paid to adjuvant endourological measures, which all have been performed on the same table.

ESWL of impacted ureteral or caliceal stones is not as successful as expected. To study this problem a model for extracorporeal shock wave lithotripsy of ureteral stones has been designed. After initial fragmentation of the outer shell of impacted stones during the first series of shock wave application those fragments are kept in place by external mucosal contact, creating a lot of new interfaces. Absorption or reflection of shock wave energy within this fragmented shell seems to be responsible for the poor success rate in these cases. In regard to our experimental and clinical results we advise pushing ureteral stones back into the renal collecting system by means of a ureteral catheter.