Thomas Knoll

2007 Guideline for the management of ureteral calculi.

TheAmericanUrologicalAssociationNephrolithiasis Clinical Guideline Panel was established in 1991. Since that time, the Panel has developed three guidelines on the management of nephrolithiasis, the most recent being a 2005 update of the original 1994 Report on the Management of Staghorn Calculi [1]. The European Association of Urology began their nephrolithiasis guideline project in 2000, yielding the publication of Guidelines on Urolithiasis, with updates in 2001 and 2006 [2]. While both documents provide useful recommendations on the management of ureteral calculi, changes in shock-wave lithotripsy technology, endoscope design, intracorporeal lithotripsy techniques, and laparoscopic expertise have burgeoned over the past five to ten years. Under the sage leadership of the late Dr. JosephW. Segura, the AUA Practice Guidelines Committee suggested to both the AUA and the EAU that they join efforts in developing the first set of internationally endorsed guidelines focusing on the changes introduced in ureteral stone management over the last decade. We therefore dedicate this report to the memory of Dr. Joseph W. Segura whose vision, integrity, and perseverance led to the establishment of the first international guideline project. This joint EAU/AUA Nephrolithiasis Guideline Panel (hereinafter the Panel) performed a systematic review of the English language literature published since 1997 and a comprehensively analyzed outcomes data from the identified studies. Based on their findings, the Panel concluded that when removal becomes necessary, SWL and ureteroscopy remain the two primary treatment modalities for the management of symptomatic ureteral calculi. Other treatments were reviewed, including medical expulsive therapy to facilitate spontaneous stone passage, percutaneous antegrade ureteroscopy, and laparoscopic and open surgical ureterolithotomy. In concurrence with the previously published guidelines of both organizations, open stone surgery is still considered a secondary treatment option. Blind basketing of ureteral calculi is not recommended. In addition, the Panel was able to provide some guidance e u r o p e a n u r o l og y 5 2 ( 2 0 0 7 ) 1 6 1 0 – 1 6 3 1

EAU Guidelines on Interventional Treatment for Urolithiasis

CONTEXT Management of urinary stones is a major issue for most urologists. Treatment modalities are minimally invasive and include extracorporeal shockwave lithotripsy (SWL), ureteroscopy (URS), and percutaneous nephrolithotomy (PNL). Technological advances and changing treatment patterns have had an impact on current treatment recommendations, which have clearly shifted towards endourologic procedures. These guidelines describe recent recommendations on treatment indications and the choice of modality for ureteral and renal calculi. OBJECTIVE To evaluate the optimal measures for treatment of urinary stone disease. EVIDENCE ACQUISITION Several databases were searched to identify studies on interventional treatment of urolithiasis, with special attention to the level of evidence. EVIDENCE SYNTHESIS Treatment decisions are made individually according to stone size, location, and (if known) composition, as well as patient preference and local expertise. Treatment recommendations have shifted to endourologic procedures such as URS and PNL, and SWL has lost its place as the first-line modality for many indications despite its proven efficacy. Open and laparoscopic techniques are restricted to limited indications. Best clinical practice standards have been established for all treatments, making all options minimally invasive with low complication rates. CONCLUSION Active treatment of urolithiasis is currently a minimally invasive intervention, with preference for endourologic techniques. PATIENT SUMMARY For active removal of stones from the kidney or ureter, technological advances have made it possible to use less invasive surgical techniques. These interventions are safe and are generally associated with shorter recovery times and less discomfort for the patient.

Shock Wave Technology and Application: An Update §

CONTEXT The introduction of new lithotripters has increased problems associated with shock wave application. Recent studies concerning mechanisms of stone disintegration, shock wave focusing, coupling, and application have appeared that may address some of these problems. OBJECTIVE To present a consensus with respect to the physics and techniques used by urologists, physicists, and representatives of European lithotripter companies. EVIDENCE ACQUISITION We reviewed recent literature (PubMed, Embase, Medline) that focused on the physics of shock waves, theories of stone disintegration, and studies on optimising shock wave application. In addition, we used relevant information from a consensus meeting of the German Society of Shock Wave Lithotripsy. EVIDENCE SYNTHESIS Besides established mechanisms describing initial fragmentation (tear and shear forces, spallation, cavitation, quasi-static squeezing), the model of dynamic squeezing offers new insight in stone comminution. Manufacturers have modified sources to either enlarge the focal zone or offer different focal sizes. The efficacy of extracorporeal shock wave lithotripsy (ESWL) can be increased by lowering the pulse rate to 60-80 shock waves/min and by ramping the shock wave energy. With the water cushion, the quality of coupling has become a critical factor that depends on the amount, viscosity, and temperature of the gel. Fluoroscopy time can be reduced by automated localisation or the use of optical and acoustic tracking systems. There is a trend towards larger focal zones and lower shock wave pressures. CONCLUSIONS New theories for stone disintegration favour the use of shock wave sources with larger focal zones. Use of slower pulse rates, ramping strategies, and adequate coupling of the shock wave head can significantly increase the efficacy and safety of ESWL.

EAU Guidelines on Diagnosis and Conservative Management of Urolithiasis

CONTEXT Low-dose computed tomography (CT) has become the first choice for detection of ureteral calculi. Conservative observational management of renal stones is possible, although the availability of minimally invasive treatment often leads to active treatment. Acute renal colic due to ureteral stone obstruction is an emergency that requires immediate pain management. Medical expulsive therapy (MET) for ureteral stones can support spontaneous passage in the absence of complicating factors. These guidelines summarise current recommendations for imaging, pain management, conservative treatment, and MET for renal and ureteral stones. Oral chemolysis is an option for uric acid stones. OBJECTIVE To evaluate the optimal measures for diagnosis and conservative and medical treatment of urolithiasis. EVIDENCE ACQUISITION Several databases were searched for studies on imaging, pain management, observation, and MET for urolithiasis, with particular attention to the level of evidence. EVIDENCE SYNTHESIS Most patients with urolithiasis present with typical colic symptoms, but stones in the renal calices remain asymptomatic. Routine evaluation includes ultrasound imaging as the first-line modality. In acute disease, low-dose CT is the method of choice. Ureteral stones <6mm can pass spontaneously in well-controlled patients. Sufficient pain management is mandatory in acute renal colic. MET, usually with α-receptor antagonists, facilitates stone passage and reduces the need for analgesia. Contrast imaging is advised for accurate determination of the renal anatomy. Asymptomatic calyceal stones may be observed via active surveillance. CONCLUSIONS Diagnosis, observational management, and medical treatment of urinary calculi are routine measures. Diagnosis is rapid using low-dose CT. However, radiation exposure is a limitation. Active treatment might not be necessary, especially for stones in the lower pole. MET is recommended to support spontaneous stone expulsion. PATIENT SUMMARY For stones in the lower pole of the kidney, treatment may be postponed if there are no complaints. Pharmacological treatment may promote spontaneous stone passage.

Cystinuria in childhood and adolescence: recommendations for diagnosis, treatment, and follow-up

Cystinuria, an autosomal-recessive disorder of a renal tubular amino acid transporter, is the cause of about 10% of all kidney stones observed in children. Different genetic characteristics are not represented by different phenotypes. The stones are formed of cystine, which is relatively insoluble at the physiological pH of urine. Without any preventive measures, the patients will suffer from recurrent stone formation throughout their life. Even with medical management, long-term outcome is poor due to insufficient efficacy and low patient compliance. Many patients suffer from renal insufficiency as a result of recurrent stone formation and repeated interventions. However, regular follow-up and optimal pharmacotherapy significantly increase stone-free intervals. Medical management is mainly based on hyperhydration and urine alkalinization. Sulfhydryl agents such as tiopronin can be added. Recurrent stone formation necessitates repeated urological interventions. These mostly minimally invasive procedures carry the risk of impairment of renal function. In adults, extracorporeal shockwave lithotripsy (SWL) as well as intracorporeal lithotripsy is often unsuccessful. However, in children SWL shows excellent results for cystine stones. In cases with large stone burden, percutaneous nephrolithotripsy (PNL) or even open surgical nephrolithotomy are preferred. This review discusses the underlying pathogenetic mechanisms and provides guidance for the diagnosis, therapy, and management of cystinuria following the recommendations of the International Cystinuria Consortium and the European Association of Urology.

Urolithiasis Through the Ages: Data on More Than 200,000 Urinary Stone Analyses

PURPOSE The incidence and prevalence of urolithiasis are increasing but clinicians also have the impression that gender and age distributions of stone formers are changing. Moreover, regional differences in stone occurrence and composition have been observed. We analyzed such trends based on a large series of urinary stone analyses. MATERIALS AND METHODS A total of 224,085 urinary stone analyses from 22 German centers were evaluated to determine the incidence of stone composition and identify age and gender distributions from 1977 to 2006. A subset of 58,682 stone analyses from 1993 to 2006 was available to identify regional differences in stone composition in Germany. RESULTS Calcium containing calculi were most common in each gender. The overall male-to-female ratio of 2.4:1 increased from 1977 (1.86:1) to 2006 (2.7:1). The predominance of male calcium stone formers was even higher among elderly patients with a 3.13:1 ratio at ages 60 to 69. Since 1997, we observed a tendency toward an increasing incidence in middle-aged patients at ages 40 to 49 years. While the rate of infection stones constantly decreased, the incidence of uric acid calculi remained stable with an overall rate of 11.7% in males and 7.0% in females with a peak at higher ages. Cystine stones remained rare at 0.4% in males and 0.7% in females. In terms of regional analyses we noted great variation in stone composition in the 2 genders. Uric acid stones were more common in the eastern and southern regions but infection stones were mostly seen in eastern regions. CONCLUSIONS In what is to our knowledge the largest series of stone analysis reported to date we identified an age and gender relationship of stone formation and composition. Regional variations are common and underline the influence of living habits, diet and standard of medical care on urinary stone formation.

480 UROLITHIASIS THROUGH THE AGES: DATA FROM MORE THAN 200,000 URINARY STONE ANALYSES

From the Departments of Urology, Sindelfingen-Boeblingen Medical Center, University of Tubingen (TK, GWN), Tubingen, Zeisigwald Clinics Bethanien (DF), Chemnitz and Malteser Hospital St. Hildegardis (DBL), Cologne and Department of Traumatology and Orthopaedics, Vivantes Klinikum Spandau (ABS) and Urinary Stone Laboratory, Institute of Laboratory Diagnostics, Vivantes Klinikum Friedrichshain (GS), Berlin, Germany

Do Patients Benefit from Miniaturized Tubeless Percutaneous Nephrolithotomy? A Comparative Prospective Study

BACKGROUND AND PURPOSE A benefit of miniaturized percutaneous nephrolithotomy (MPCNL) compared with conventional percutaneous nephrolithotomy (PCNL) has not been demonstrated as yet. Thus, the aim of this study was to evaluate the outcome of conventional vs MPCNL and to determine if MPCNL offers an advantage for the patient. PATIENTS AND METHODS A prospective, nonrandomized series of 50 consecutive patients with solitary calculi (lower pole or the renal pelvis) were treated either by conventional PCNL (26F) or MPCNL (18F). Ultrasound or holmium laser were used for lithotripsy. Patients were treated tubeless after uncomplicated MPCNL, with thrombin-matrix tract closure and antegrade Double-J catheter placement. After PCNL, all patients received 22F nephrostomies. Demographic data, stone characteristics, perioperative course, and complication rates were assessed. RESULTS Patients characteristics were comparable in both groups, except for stone size, which was 18 +/- 8 mm (MPCNL) and 23 +/- 9 (PCNL; P = 0.042). Operative time was comparable in both groups (48 +/- 17 vs 57 +/- 22 min, not significant [NS]). After MPCNL, 96% were stone free at day 1 vs 92% after PCNL (NS). Significant complications did not occur in both groups. Minor complications were: Fever, 12% (MPCNL) vs 20% (PCNL; NS); bleeding, 4% vs 8%; perforations, 0% vs 4% (all NS). Overall outcome was not influenced by body mass index. Calcium oxalate stones were predominant with 75%. Patients after tubeless MPCNL had less pain (visual analogue score, 3 +/- 3 vs 4 +/- 3; P = 0.048.) and needed slightly less additional pain medication (25 +/- 12 mg/d vs 37 +/- 10 mg/d piritramid; NS). Hospital stay was significantly shorter after MPCNL (3.8 +/- 28 vs 6.9 +/- 3.5 d; P = 0.021.). CONCLUSIONS Both techniques were safe and effective for the management of renal calculi. While stone-free rates were comparable in our series, MPCNL showed advantages in terms of shorter hospital stay and postoperative pain. The lower stone burden and the tubeless fashion of MPCNL, however, might have influenced these results.

Laser Treatment of Benign Prostatic Obstruction: Basics and Physical Differences

CONTEXT Laser treatment of benign prostatic obstruction (BPO) has become more prevalent in recent years. Although multiple surgical approaches exist, there is confusion about laser-tissue interaction, especially in terms of physical aspects and with respect to the optimal treatment modality. OBJECTIVE To compare available laser systems with respect to physical fundamentals and to discuss the similarities and differences among introduced laser devices. EVIDENCE ACQUISITION The paper is based on the second expert meeting on the laser treatment of BPO organised by the European Association of Urology Section of Uro-Technology. A systematic literature search was also carried out to cover the topic of laser treatment of BPO extensively. EVIDENCE SYNTHESIS The principles of generation of laser radiation, laser fibre construction, the types of energy emission, and laser-tissue interaction are discussed in detail for the laser systems used in the treatment of BPO. The most relevant laser systems are compared and their physical properties discussed in depth. CONCLUSIONS Laser treatment of BPO is gaining widespread acceptance. Detailed knowledge of the physical principles allows the surgeon to discriminate between available laser systems and their possible pitfalls to guarantee high safety levels for the patient.

Systematic Evaluation of a Recently Introduced 2-μm Continuous-Wave Thulium Laser for Vaporesection of the Prostate

BACKGROUND AND PURPOSE A novel 2-microm continuous wave (CW) thulium laser device for interventional treatment of benign prostatic hyperplasia was recently introduced into clinical practice and is postulated to have several advantages over more established laser devices. A systematic ex-vivo evaluation of the thulium laser was undertaken to compare the results to transurethral resection of the prostate (TURP) and the potassium-titanyl-phosphate (KTP) laser as reference standard methods. MATERIALS AND METHODS The RevoLix CW thulium laser system was evaluated in the well-established model of the isolated blood-perfused porcine kidney to determine its tissue ablation capacity and hemostatic properties at different power settings. Histologic examination of the ablated tissue followed. The results were compared to the reference standards, TURP and 80-W KTP laser. RESULTS At a power setting of 70 W, the CW thulium laser displays a higher tissue ablation rate, reaching 6.56+/-0.69 g after 10 minutes, compared to the 80 W KTP laser (3.99+/-0.48 g; P<0.05). Only 30 seconds were needed to resect tissue with the same surface area using TURP, resulting in 8.28+/-0.38 g of tissue removal. With a bleeding rate of 0.16+/-0.07 g/min, the CW thulium laser offers hemostatic properties equal to those of the KTP laser (0.21+/-0.07 g/min), and a significantly reduced bleeding rate compared to TURP (20.14+/-2.03 g/min; P<0.05). The corresponding depths of the coagulation zones were 264.7+/-41.3 microm for the CW thulium laser, 666.9+/-64.0 microm for the KTP laser (P<0.05), and 287.1+/-27.5 microm for TURP. CONCLUSION In this standardized ex-vivo investigation, the 2-microm CW thulium laser offered a higher tissue ablation capacity and similar hemostatic properties as those of the KTP laser, and in comparison to TURP both tissue ablation and the bleeding rate were significantly reduced.