Ureteral stricture rate after endoscopic treatments for urolithiasis and related risk factors: systematic review and meta-analysis.

PURPOSE: We aimed to accurately determine ureteral stricture (US) rates following urolithiasis treatments and their related risk factors. METHODS: We conducted a systematic review and meta-analysis following the PRISMA guidelines using databases from inception to November 2023. Studies were deemed eligible for analysis if they included ≥ 18 years old patients with urinary lithiasis (Patients) who were subjected to endoscopic treatment (Intervention) with ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), or shock wave lithotripsy (SWL) (Comparator) to assess the incidence of US (Outcome) in prospective and retrospective studies (Study design). RESULTS: A total of 43 studies were included. The pooled US rate was 1.3% post-SWL and 2.1% post-PCNL. The pooled rate of US post-URS was 1.9% but raised to 2.7% considering the last five years' studies and 4.9% if the stone was impacted. Moreover, the pooled US rate differed if follow-ups were under or over six months. Patients with proximal ureteral stone, preoperative hydronephrosis, intraoperative ureteral perforation, and impacted stones showed higher US risk post-endoscopic intervention with odds ratio of 1.6 (P = 0.05), 2.6 (P = 0.009), 7.1 (P < 0.001), and 7.47 (P = 0.003), respectively. CONCLUSIONS: The overall US rate ranges from 0.3 to 4.9%, with an increasing trend in the last few years. It is influenced by type of treatment, stone location and impaction, preoperative hydronephrosis and intraoperative perforation. Future standardized reporting and prospective and more extended follow-up studies might contribute to a better understanding of US risks related to calculi treatment.

The hydrodynamic basis of the vacuum cleaner effect in continuous-flow PCNL instruments: an empiric approach and mathematical model.

PURPOSE: Passive removal of stone fragments in the irrigation stream is one of the characteristics in continuous-flow PCNL instruments. So far the physical principle of this so-called vacuum cleaner effect has not been fully understood yet. The aim of the study was to empirically prove the existence of the vacuum cleaner effect and to develop a physical hypothesis and generate a mathematical model for this phenomenon. METHODS: In an empiric approach, common low-pressure PCNL instruments and conventional PCNL sheaths were tested using an in vitro model. Flow characteristics were visualized by coloring of irrigation fluid. Influence of irrigation pressure, sheath diameter, sheath design, nephroscope design and position of the nephroscope was assessed. Experiments were digitally recorded for further slow-motion analysis to deduce a physical model. RESULTS: In each tested nephroscope design, we could observe the vacuum cleaner effect. Increase in irrigation pressure and reduction in cross section of sheath sustained the effect. Slow-motion analysis of colored flow revealed a synergism of two effects causing suction and transportation of the stone. For the first time, our model showed a flow reversal in the sheath as an integral part of the origin of the stone transportation during vacuum cleaner effect. The application of Bernoulli's equation provided the explanation of these effects and confirmed our experimental results. CONCLUSIONS: We widen the understanding of PCNL with a conclusive physical model, which explains fluid mechanics of the vacuum cleaner effect.

[Partial Nephrectomy in cT1 Renal Tumours: Conventional Laparoscopic Partial Nephrectomy Compared with LESS Partial Nephrectomy in SITUS Technique]. / Nierenteilresektion bei cT1 Nierentumoren: Vergleich der konventionellen laparoskopischen Nierenteilresektion mit der LESS Nierenteilresektion in SITUS-Technik.

BACKGROUND: Partial nephrectomy is the treatment of choice for clinical stage 1 renal tumours. Open partial nephrectomy is the standard operative technique. The use of minimally-invasive strategies such as laparoscopic, robot-assisted partial nephrectomy or laparoendoscopic single site (LESS) partial nephrectomy has increased in recent years. PATIENTS/MATERIAL AND METHODS: In this retrospective study, patients undergoing laparoscopic partial nephrectomy between December 2008 and November 2013 were evaluated. All patients presented with renal lesions suspicious for malignancy. Operations were performed as conventional laparoscopic transperitoneal partial nephrectomies (cLPN) or LESS partial nephrectomies (LESS-PN) in SITUS technique (single incision transumbilical surgery). The aim of the study was to compare perioperative outcome parameters such as duration of surgery, time of ischaemia, complications, need for transfusion, conversion rates, changes in renal function and duration of hospital stay in both groups. RESULTS: A total of 85 laparoscopic partial nephrectomies were performed in this study (72 cLPN and 13 LESS-PN). The average tumour size was 2.68±1.47 cm (cLPN) vs. 2.46±1.11 cm (LESS-PN). The mean duration of surgery was 175.17±50.026 min (cLPN) and 185.77±35.991 min (LESS-PN). 45 (62.5%) operations (cLPN) vs. 10 (76.9%) (LESS-PN) were performed in zero-ischaemia technique. There were no significant differences in perioperative outcome parameters between both groups. Postoperative complication rates (Clavien-Dindo≥3) were 11.1% (cLPN) vs. 7.7% (LESS-PN). CONCLUSIONS: LESS partial nephrectomy in SITUS technique is an attractive alternative to conventional laparoscopic and open partial nephrectomy.

Guía clínica de la Asociación Europea de Urología sobre tecnologías láser / European Association of Urology Guidelines on Laser Technologies

Contexto: La Oficina de Guías Clínicas de la Asociación Europea de Urología (EAU) ha establecido un panel de trabajo de guías clínicas para analizar la evidencia científica publicada en la literatura mundial sobre láseres en la práctica urológica. Objetivo: Revisar el origen físico y los aspectos fisiológicos y técnicos de la utilización de los láseres en Urología, así como los actuales resultados clínicos de estas nuevas tecnologías en evolución, junto con recomendaciones para la aplicación de los láseres en Urología. El objetivo principal de esta presentación estructurada de la base de la evidencia actual en esta área es ayudar a los médicos a tomar decisiones informadas con respecto al uso de los láseres en su práctica clínica. Adquisición de la evidencia: Se diseñaron búsquedas estructuradas de la literatura que utilizan un consultor experto para cada sección de este documento. Se realizaron búsquedas en la base de datos Cochrane de Revisiones Sistemáticas, el registro Cochrane Central de Ensayos Controlados y Medline y Embase en la plataforma Dialog/DataStar. Se utilizó la terminología controlada de las respectivas bases de datos y se analizaron tanto Medical Subject Headings como EMTREE para conocer los términos de entrada relevantes. Se identificó una revisión Cochrane. Síntesis de la evidencia: Dependiendo de la fecha de publicación la evidencia de los diferentes tratamientos con láser es heterogénea. La evidencia disponible permite clasificar los tratamientos como alternativas seguras para la terapia de la obstrucción del tracto urinario inferior en diferentes escenarios clínicos, tales como la retención urinaria refractaria, la anticoagulación y la medicación antiplaquetaria. El tratamiento con láser para el cáncer de vejiga solo se debe utilizar en un ensayo clínico o para pacientes que no son adecuados para el tratamiento convencional, debido a comorbilidades u otras complicaciones. Para el tratamiento de la litiasis urinaria y la endoureterotomía retrógrada los láseres proporcionan una herramienta estándar para aumentar el procedimiento endourológico. Conclusiones: En la obstrucción prostática benigna (OPB) la vaporización por láser, la resección o la enucleación son opciones de tratamiento alternativas. El tratamiento estándar para la OPB sigue siendo la resección transuretral de la próstata para próstatas de tamaño pequeño a moderado y la prostatectomía abierta para próstatas grandes. La energía láser es un método de tratamiento óptimo para la desintegración de cálculos urinarios. El uso de láseres para el tratamiento de los tumores de vejiga y en la laparoscopia sigue en investigación (AU)

Context: The European Association of Urology (EAU) Guidelines Office has set up a guideline working panel to analyse the scientific evidence published in the world literature on lasers in urologic practice. Objective: Review the physical background and physiologic and technical aspects of the use of lasers in urology, as well as current clinical results from these new and evolving technologies, together with recommendations for the application of lasers in urology. The primary objective of this structured presentation of the current evidence base in this area is to assist clinicians in making informed choices regarding the use of lasers in their practice. Evidence acquisition: Structured literature searches using an expert consultant were designed for each section of this document. Searches were carried out in the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Medline and Embase on the Dialog/DataStar platform. The controlled terminology of the respective databases was used, and both Medical Subject Headings and EMTREE were analysed for relevant entry terms. One Cochrane review was identified. Evidence synthesis: Depending on the date of publication, the evidence for different laser treatments is heterogeneous. The available evidence allows treatments to be classified as safe alternatives for the treatment of bladder outlet obstruction in different clinical scenarios, such as refractory urinary retention, anticoagulation, and antiplatelet medication. Laser treatment for bladder cancer should only be used in a clinical trial setting or for patients who are not suitable for conventional treatment due to comorbidities or other complications. For the treatment of urinary stones and retrograde endoureterotomy, lasers provide a standard tool to augment the endourologic procedure.Conclusions: In benign prostatic obstruction (BPO), laser vaporisation, resection, or enucleation are alternative treatment options. The standard treatment for BPO remains transurethral resection of the prostate for small to moderate size prostates and open prostatectomy for large prostates. Laser energy is an optimal treatment method for disintegrating urinary stones. The use of lasers to treat bladder tumours and in laparoscopy remains investigational (AU)

[European Association of Urology guidelines on laser technologies]. / Guía clínica de la Asociación Europea de Urología sobre tecnologías láser.

CONTEXT: The European Association of Urology (EAU) Guidelines Office has set up a guideline working panel to analyse the scientific evidence published in the world literature on lasers in urologic practice. OBJECTIVE: Review the physical background and physiologic and technical aspects of the use of lasers in urology, as well as current clinical results from these new and evolving technologies, together with recommendations for the application of lasers in urology. The primary objective of this structured presentation of the current evidence base in this area is to assist clinicians in making informed choices regarding the use of lasers in their practice. EVIDENCE ACQUISITION: Structured literature searches using an expert consultant were designed for each section of this document. Searches were carried out in the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Medline and Embase on the Dialog/DataStar platform. The controlled terminology of the respective databases was used, and both Medical Subject Headings and EMTREE were analysed for relevant entry terms. One Cochrane review was identified. EVIDENCE SYNTHESIS: Depending on the date of publication, the evidence for different laser treatments is heterogeneous. The available evidence allows treatments to be classified as safe alternatives for the treatment of bladder outlet obstruction in different clinical scenarios, such as refractory urinary retention, anticoagulation, and antiplatelet medication. Laser treatment for bladder cancer should only be used in a clinical trial setting or for patients who are not suitable for conventional treatment due to comorbidities or other complications. For the treatment of urinary stones and retrograde endoureterotomy, lasers provide a standard tool to augment the endourologic procedure. CONCLUSIONS: In benign prostatic obstruction (BPO), laser vaporisation, resection, or enucleation are alternative treatment options. The standard treatment for BPO remains transurethral resection of the prostate for small to moderate size prostates and open prostatectomy for large prostates. Laser energy is an optimal treatment method for disintegrating urinary stones. The use of lasers to treat bladder tumours and in laparoscopy remains investigational.

The use of mannitol in partial and live donor nephrectomy: an international survey.

PURPOSE: Animal studies have shown the potential benefits of mannitol as renoprotective during warm ischemia; it may have antioxidant and anti-inflammatory properties and is sometimes used during partial nephrectomy (PN) and live donor nephrectomy (LDN). Despite this, a prospective study on mannitol has never been performed. The aim of this study is to document patterns of mannitol use during PN and LDN. MATERIALS AND METHODS: A survey on the use of mannitol during PN and LDN was sent to 92 high surgical volume urological centers. Questions included use of mannitol, indications for use, physician responsible for administration, dosage, timing and other renoprotective measures. RESULTS: Mannitol was used in 78 and 64 % of centers performing PN and LDN, respectively. The indication for use was as antioxidant (21 %), as diuretic (5 %) and as a combination of the two (74 %). For PN, the most common dosages were 12.5 g (30 %) and 25 g (49 %). For LDN, the most common doses were 12.5 g (36.3 %) and 25 g (63.7 %). Overall, 83 % of centers utilized mannitol, and two (percent or centers??) utilized furosemide for renoprotection. CONCLUSIONS: A large majority of high-volume centers performing PN and LDN use mannitol for renoprotection. Since there are no data proving its value nor standardized indication and usage, this survey may provide information for a randomized prospective study.

Laparoscopic radical cystectomy: initial experience using the single-incision triangulated umbilical surgery (SITUS) technique.

INTRODUCTION: As could be demonstrated for simple and radical nephrectomy, single-incision triangulated umbilical surgery (SITUS) is an interesting alternative to laparoscopic single-site surgery. We present our initial experience with the SITUS technique in radical cystectomy. MATERIALS AND METHODS: Between September 2010 and September 2011, eight patients underwent SITUS radical cystectomy (SITUS Cx), pelvic lymph node dissection and extracorporeal urinary diversion. A cutaneous ureterostomy was performed in three, an ileum conduit in one and an ileal neobladder in four patients. Data were collected prospectively, including patients' characteristics, intraoperative parameters, pathological stage and postoperative outcome. RESULTS: Mean age of the patients was 67 years and the mean body mass index 24 kg/m(2). SITUS Cx was successfully completed in all patients without conversion to conventional laparoscopic or open surgery. Mean surgical time was 434 min and mean estimated blood loss 643 ml. No major intra- or postoperative surgical complications occurred. All patients recovered quickly reporting low postoperative pain levels. Mean hospital stay was 16 (7-24 days). Histopathological evaluation revealed a mean of 16 (6-33) retrieved lymph nodes and no positive margins. CONCLUSION: In the present experience, SITUS Cx proved to be feasible with surgical outcome comparable to conventional techniques. Because SITUS Cx combines the advantages of traditional laparoscopy (straight instruments and triangulation) with those of single-port surgery (superior cosmesis and minimal invasiveness), it presents an attractive alternative to other minimally invasive techniques.

[Transurethral en bloc resection of non-muscle invasive bladder cancer. What is the state of the art?]. / Transurethrale En-bloc-Resektion nicht muskelinvasiver Harnblasenkarzinome. Wo stehen wir heute?

Bladder cancer of the urothelium is the second most common malignancy among urological tumors. In view of a worldwide aging population and the fact that increased incidence rates are associated with higher age, new socioeconomic challenges will appear. Even nowadays the treatment of bladder cancer bears the highest lifetime treatment costs per patient among all forms of cancer. In conjunction with higher comorbidity rates among older patients urologists are facing new challenges in the treatment and care of patients with bladder cancer. The standard treatment for non-muscle invasive bladder cancer (NMIBC) is monopolar transurethral resection using resection loops (TURB). Based on experience in the surgical treatment of benign prostatic hyperplasia, different concepts of en bloc resection of bladder tumors using alternative energy resources (e.g. holmium laser, thulium laser and the water-jet HybridKnife) have been developed. Goals of new treatment modalities are reduction of perioperative and postoperative comorbidities, better pathological work-up of the specimens and increased recurrence-free survival. Postulated advantages using laser devices are a more precise cutting line as well as better hemostasis. The evidential value of this review is limited due to the lack of randomized, prospective studies. However, there is a tendency towards a limitation of perioperative and postoperative morbidities as well as higher chance of well-preserved tissues for better pathohistological evaluation using en bloc resection methods. More studies with long-term follow-up periods and better randomization are needed to clarify whether en bloc strategies provide better long-term oncological survival.

Waterjet hydrodissection: first experiences and short-term outcomes of a novel approach to bladder tumor resection.

INTRODUCTION: TURB is the standard approach to bladder tumors but suffers from several disadvantages. Waterjet hydrodissection is a new technology for removing superficial tumors in the GI tract promising to preserve the histological structures of biopsy specimens with favorable long-term results as recent studies have shown. The aim of this study was to show the feasibility and applicability of waterjet hydrodissection for removing papillary superficial bladder tumors. MATERIALS AND METHODS: In five patients diagnosed with superficial papillary bladder tumor, transurethral submucosal dissection was conducted using the T-type I-Jet HybridKnife (Erbe, Tuebingen). The resection edges were labeled by means of electrical coagulation with the HybridKnife. Subsequently, a submucosal fluid cushion specific to the tissue layer was formed by the waterjet implementation function of the HybridKnife, thereby elevating the tumorous tissue. The tumor was endoscopically extracted with a retrieval bag. Biopsy specimens of the tumor edges and base were subsequently collected. RESULTS: All tumors could be resected en bloc, and the lamina propria was intact in all specimens, allowing the pathologist to distinguish between superficial and invasive tumors. Pathological analysis confirmed R0 resection in all samples. CONCLUSION: These initial results prove the feasibility of waterjet hydrodissection for removing bladder tumors. In contrast to conventional TURB, this new technique allows the pathologist to assess the entire lamina propria and the resection edges due to the en-bloc resection and to determine invasiveness as well as R0 versus R1 resection. These first results are promising, long-term oncological follow-up, and prospective randomized surveys investigating the recurrence rate have to be evaluated.

Economic aspects of bladder cancer: what are the benefits and costs?

OBJECTIVE: Bladder cancer (BC) has the highest lifetime treatment costs per patient of all cancers. The high recurrence rate and ongoing invasive monitoring requirement are the key contributors to the economic and human toll of this disease. The purpose of this paper was to utilize the recent literature to identify opportunities for improving the benefits and costs of BC care. METHODS: A PubMed search was performed of recent publications concerning (BC) cost-effectiveness. We reviewed studies, reviews, opinion papers and cost-effectiveness analyses, focusing primarily on non-muscle-invasive bladder cancer (Ta/T1; NMIBC). RESULTS: New diagnostic tools such as urine markers may assist in more cost-effectively detecting BC at an earlier stage, however, these markers cannot replace the cystoscopy, which is the current standard of care. A photodynamic diagnostic tool (PDD) using hexylaminolevulinate (Hexvix) enhances tumor visibility and improves transurethral resection of bladder cancer (TURB) results, potentially reducing recurrence rates and lowering treatment costs. While the importance of BC research has been acknowledged, research investment has been continuously reduced during the last 5 years. CONCLUSIONS: The economic burden of BC is well-characterized in the literature. This study suggests that new technologies (i.e., urine-based tests, PDD) and therapeutic regimes (intravesical chemotherapy, adjuvant immunotherapy) have significant potential to improve the diagnosis, treatment and on-going monitoring of BC patients, with potential improvements in clinical outcomes and concurrent cost-savings. A renewed interest and investment in BC research are required to ensure future advancements.

Dual-energy CT for the characterization of urinary calculi: In vitro and in vivo evaluation of a low-dose scanning protocol.

The efficiency and radiation dose of a low-dose dual-energy (DE) CT protocol for the evaluation of urinary calculus disease were evaluated. A low-dose dual-source DE-CT renal calculi protocol (140 kV, 46 mAs; 80 kV, 210 mAs) was derived from the single-energy (SE) CT protocol used in our institution for the detection of renal calculi (120 kV, 75 mAs). An Alderson-Rando phantom was equipped with thermoluminescence dosimeters and examined by CT with both protocols. The effective doses were calculated. Fifty-one patients with suspected or known urinary calculus disease underwent DE-CT. DE analysis was performed if calculi were detected using a dedicated software tool. Results were compared to chemical analysis after invasive calculus extraction. An effective dose of 3.43 mSv (male) and 5.30 mSv (female) was measured in the phantom for the DE protocol (vs. 3.17/4.57 mSv for the SE protocol). Urinary calculi were found in 34 patients; in 28 patients, calculi were removed and analyzed (23 patients with calcified calculi, three with uric acid calculi, one with 2,8-dihyxdroxyadenine-calculi, one patient with a mixed struvite calculus). DE analysis was able to distinguish between calcified and non-calcified calculi in all cases. In conclusion, dual-energy urinary calculus analysis is effective also with a low-dose protocol. The protocol tested in this study reliably identified calcified urinary calculi in vivo.

Laparoscopic heminephroureterectomy for duplex kidney anomalies in the pediatric population.

OBJECTIVE: Despite increasing acceptance of laparoscopy in pediatric urology, few published data are available on laparoscopic heminephroureterectomy in patients with duplex kidney anomalies. In the present study, we report our own experiences with this technique. PATIENTS AND METHODS: From August 2003 to January 2006, five laparoscopic heminephroureterectomies were performed in four girls with a mean age of 41 (9-67) months. In all cases, a non-functioning upper pole with an obstructive (n=4) or refluxing (n=1) megaureter was found. The upper pole was resected laparoscopically en bloc with the megaureter using three to four trocars. RESULTS: Mean follow-up was 42.4 (+/-7.9) months. All procedures were performed successfully without conversion to open surgery with a mean operative time of 190 (170-210)min. Blood loss was minimal and no intraoperative complications occurred. Despite chronic inflammation in the resected specimens, the patients showed no clinical signs of infection postoperatively. The average length of hospital stay was 5.6 (4-7) days. All patients were followed using duplex sonography. CONCLUSIONS: These data demonstrate that, even in infants, laparoscopic heminephroureterectomy is feasible and associated with minimal morbidity, a better cosmetic result and a shorter hospital stay compared to open surgery. The main disadvantage of the laparoscopic approach is a longer operative time. Laparoscopic heminephroureterectomy is a technically demanding procedure and should be performed only in specialized centers.

[Minimally invasive percutaneous nephrolitholapaxy (MIP)]. / Minimal-invasive perkutane Nephrolitholapaxie (MIP).

Minimally invasive percutaneous nephrolithopaxy (MIP) was developed to combine the excellent stone-free rates of the conventional percutaneous nephrolithopaxy (PCNL) technique with the low morbidity of the miniaturized PCNL (Mini-Perc) and, at the same time, achieve a high level of patient comfort. The procedure is characterized not only by the diameter of the miniaturized 18-Fr Amplatz sheath that was adopted from the Mini-Perc but also by the following features: ultrasound-guided puncture of the kidney; single-step dilatation of the access tract; ballistic lithotripsy; a low-pressure irrigation system together with stone retraction by irrigation with a specially designed nephroscope sheath, for the so-called vacuum cleaner effect; and a sealed and tubeless access tract with primary closure of the channel independent of hemorrhage and without a second-look procedure.The results of the first 57 patients demonstrate primary stone-free rates of 92.9% with operating times averaging 62 (25-123) min. Severe complications, such as sepsis or bleeding requiring blood transfusion, did not occur. The high and predictable stone-free rate and a low morbidity comparable to that of ureteroscopy and extracorporeal shock-wave lithotripsy make MIP an attractive option for patients and urologists. The "vacuum cleaner effect" with quick removal of stone fragments reduces operating time and prevents new stone formation by avoiding residual fragments. The direct and primary closure of the access tract increases patient comfort and is justified by the reintervention rate of less than 8% in the presented cohort.The lack of a need for second-look nephroscopies, the vacuum cleaner effect, improved patient comfort without nephrostomy tubes, as well as surgery times comparable to that of traditional PCNL demonstrate a consequent evolution of the Mini-Perc. MIP therefore represents a promising and future-oriented module in modern stone therapy.

[Bioartificial urothelium generated from bladder washings. A future therapeutic option for reconstructive surgery]. / Bioartifizielles autologes Urothel etabliert aus Spülungen der Harnblase. Eine zukünftige Therapieoption für die rekonstruktive Urologie.

Reconstructive surgery of lower urinary tract disorders can be limited by a shortage of adequate autologous tissue. Tissue engineering is an option for surgical reconstruction with evolved biological substitutes. Urethral repair with bioartificial urothelial implants can be an innovative method for sustained urothelial regeneration in situ. The needed urothelial cells are commonly isolated from native urothelium requiring surgery.The aim of this study was to establish primary human urothelial cell cultures from bladder washings in serum-free media and to generate urothelial tissue without seeding of matrices in a feeder cell-free system. It could be demonstrated that under these conditions bioartificial urothelium can be developed successfully from bladder washings. Its multilayered cellular structure and the initial differentiation in vitro, similar to native-grown urothelial tissue, are promising with regard to intended clinical application. Current work focuses on establishing cell culture techniques according to legal regulations, terminal differentiation of the urothelial constructs in vitro, and techniques to surgically implant lab-grown bioartificial urothelium.

[Lower pole calyceal stones]. / Der untere Kelchstein.

Due to its particular anatomical position below the ureteropelvic junction, the lower pole group of calices plays a special role in the treatment of nephrolithiasis. The extracorporeal shock-wave lithotripsy (ESWL) often attains dissatisfactory stone-free rates, even after optimal disintegration of lower pole stones, and thus necessitates secondary therapeutic procedures. Due to the favorable stone-free rates, retrograde intrarenal surgery with its low complication rate has taken up an important role in the treatment of lower pole stones since the development of modern flexible ureterorenoscopes. The long treatment times in the case of a large stone burden and considerable costs for materials constitute limiting factors. In line with the advancement of percutaneous nephrolitholapaxy (PCNL), a promising method also for the treatment of larger lower pole stones is available today with minimally invasive PCNL (MIP).

[MR aspect of the prostate in CPPS patients (chronic pelvic pain syndrome)]. / MR-Befundmuster der Prostata bei Patienten mit CPP Syndrom (chronic pelvic pain syndrome).

PURPOSE: To describe typical morphological patterns of abacterial prostatitis using magnetic resonance imagine (MRI) in chronic pelvic pain syndrome patients including spectroscopy. MATERIALS AND METHODS: 18 patients (age range between 25 and 67 years, average 46.2 years) with recurrent chronic pelvic pain syndrome for at least 3 months were evaluated clinically in the urological department and included if there were no suspicious findings from endorectal digital palpation and if their PSA values were < 5 ng/ml. A retrospective analysis of these 18 patients with 30 contrast-enhanced MRI investigations with endorectal coils in 28 of 30 cases was performed with a 1.5T MRI. T 2w signal intensity (SI) and spectroscopy data (9 / 18 patients) were acquired for the normal peripheral zone, the central zone, for the peripheral zone suspected of inflammation and for the muscle including SI ratios for the unaltered and the suspicious inflammatory peripheral zone. RESULTS: Typical MR patterns of signal alterations suspected of inflammation of CPPS patients were able to be detected as T 2w hypointense triangular, stringy (n = 12, 66.6 %) contrast-enhancing signal alterations without a nodular shape with well circumscribed margins of the capsula and without pericapsular signal alterations. In 6 patients changes also had a triangular but more homogeneous aspect (33.3 %). Three patients had an additional periurethral uptake (16.6 %). T 2w SI measurements and T 2w SI ratios showed much lower values for the peripheral zone suspected of inflammation as compared to the normal peripheral zone of the prostate (277.29 STD 77.5 to 432.9 STD 112.02 and 4.94 STD 1.47 to 7.58 STD 2.01 respectively). The spectroscopic analysis of the signal alterations suspected of inflammation showed normal Cholin+Creatin/Citrate SI ratio values in 3 patients (SI < 0.5), ratios suspected of low grade cancer in 3 patients (SI 0.5 and < 0.7) and ratios suspected of intermediate grade prostate cancer in 3 patients (SI > 0.7 and < 3.0). CONCLUSIONS: We saw typical MR patterns in CPPS patients. However, spectroscopy can mimic findings of cancer so that the knowledge of typical morphological patterns and a solid clinical evaluation play a major role in the diagnosis of CPPS.

[Laparoscopic pyeloplasty in a complicated duplicated collecting system]. / Laparoskopische Nierenbeckenplastik bei komplizierter Doppelniere.

Laparoscopic pyeloplasty has been established as an effective and minimally invasive technique for treating ureteropelvic junction obstruction. Only case reports are available describing the use of laparoscopic pyeloplasty in patients with duplicated collecting systems. We report the case of a patient presenting with a short stenotic connection between the hydronephrotic lower pole system and a solitary ureter coming from the upper pole. In this patient, a side-to-side anastomosis between the renal pelvis and the ureter was successfully performed. The present data demonstrate that laparoscopic pyeloplasty is an applicable tool even in patients with upper urinary tract anomalies such as duplicated collecting systems.

[Technical innovations in endourological stone therapy]. / Technische Innovationen in der endoskopischen Steintherapie.

Endoscopic stone management is a field of consistent technical innovation. For ureterorenoscopy, flexible scopes capable of 270 degrees deflection have allowed access to the complete urinary tract, including the lower-pole renal calculi. To counter the flaw of high repair costs, new-generation flexible ureterorenoscopes feature significantly greater durability and a less frequent need for repair. The development and improvement of auxiliary instruments such as access sheaths has facilitated the procedures, reduced complications, and improved the stone-free rates. A similar trend is seen for percutaneous nephrolitholapaxy (PCNL). Development is directed at miniaturised instruments such as the mini-PCNL. Especially in combination with a tubeless procedure in which a routine nephrostomy after PCNL is omitted and the nephrostomy tract is closed using hemostyptic sealant, similar success rates are achieved, with fewer complications and shorter hospital stays.

[Use of a gelatine-thrombin matrix for closure of the access tract without a nephrostomy tube in minimally invasive percutaneous nephrolitholapaxy]. / Die Verwendung von Gelatine-Thrombin-Matrix zum Verschluss des Arbeitskanals bei der nephrostomielosen minimal-invasiven perkutanen Nephrolitholapaxie.

BACKGROUND: The spectrum of percutaneous stone treatment was significantly widened following the introduction of the miniaturized percutaneous nephrolitholapaxy. At the end of the procedure usually a nephrostomy tube was placed to avoid urine paravasation and prolonged bleeding. In this work the tube-less mini-PCNL with direct closure of the access tract was compared to traditional mini-PCNL with placement of the nephrostomy tube. PATIENTS AND METHODS: Twenty consecutive patients undergoing mini-PCNL with placement of a nephrostomy tube at the end of the procedure were compared to 20 consecutive patients with direct closure of the access tracts following percutaneous stone removal. Clinical data like decrease in Hb, complications, need for analgesics and duration of hospital stay were compared. RESULTS: Both groups underwent the procedure without complications. There was no need for blood transfusions. The difference in total analgetic dose was not statistically significant; however, patients in the nephrostomy group needed analgetics for a longer period of time. There was no difference in duration of hospital stay (3.2 days in the tube-less group versus 3.4 days in the nephrostomy group). The primary stone-free rate was higher in the group with direct closure of the access tract (95 versus 85%). CONCLUSIONS: Closure of the percutaneous access following mini-PCNL with a gelatine-thrombin-haemostatic sealant is a safe alternative to the commonly used nephrostomy tube and can help to reduce postoperative pain and patient discomfort.

[Tissue engineering and stem cell research in urology for a reconstructive or regenerative treatment approach]. / "Tissue engineering" und Stammzellforschung in der Urologie für den rekonstruktiven bzw. regenerativen Therapieansatz.

With the involvement of clinical reconstructive urology in the field of tissue engineering, outstanding results have been achieved in basic research as well as in some clinics. Stem cell research has even opened up possibilities for regenerative aspects. In close cooperation with various disciplines, the Department of Urology at the University of Tübingen investigates different clinical aspects with regard to reconstructive and regenerative urology. The regeneration of the external urethral sphincter requires functionally integrated muscle cells. In addition stricture reconstruction with multilayer urothelium should become less invasive and the re-stricture rate reduced. After the application of differentiating stem cells was proven, the clinical setting needed to be set for legal issues. In addition to the specification of culture media and verification in the animal model, the possibility to harvest omnipotent stem cells out of human testis and to differentiate those into the three germ layers was demonstrated. With the reduced invasiveness of harvesting the urothelium cells by a bladder wash using specific culture fluids, the cell culture was significantly improved enabling successful creation of urothelium by stratification. In addition urothelial cells in a matrix are further improved for endoscopic application. The close cooperation of different disciplines shortens the time to develop therapeutic approaches with a close clinical relationship in reconstructive and regenerative urology.