[Image-guided biopsy of the prostate gland]. / Bildgesteuerte Biopsie der Prostata.

The recommendations on carrying out a multiparametric magnetic resonance imaging (mpMRI) for the primary diagnostics and during active surveillance of prostate cancer, include as a consequence an image-guided sampling from conspicuous areas. In doing so, the information on the localization provided by mpMRI is used for a targeted biopsy of the area suspected of being a tumor. The targeted sampling is mainly performed under sonographic control and after fusion of MRI and ultrasound but can also be (mostly in special cases) carried out directly in the MRI scanner. In an ultrasound-guided biopsy, it is vital to coregister the MR images with the ultrasound images (segmentation of the contour of the prostate and registration of suspect findings). This coregistration can either be carried out cognitively (transfer by the person performing the biopsy alone) or software based. Each method shows specific advantages and disadvantages in the prioritization between diagnostic accuracy and resource expenditure.

Drain placement can safely be omitted for open partial nephrectomy: Results from a prospective randomized trial.

OBJECTIVES: To examine the benefit of drain placement during open partial nephrectomy. METHODS: Overall, 106 patients treated with open partial nephrectomy were enrolled in a prospective randomized trial. Based on the randomization, a drain was placed or omitted. Complications were assessed according to the Clavien classification. Pain level and requirement for analgesics was evaluated according to a customized pattern. RESULTS: There was no significant difference in the two groups regarding age, body mass index, American Society of Anesthesiologists score, tumor size and nephrometry (preoperative aspects and dimensions used for an anatomical classification). In terms of overall and drain-related complications, no advantage of placing a drain could be proven (P = 0.249). Patients with a drain suffered from a significantly higher pain level (P = 0.01) and showed prolonged mobilization (P < 0.001). There was no difference in bowel movements and requirement of additional analgesics (P = 0.347 and 0.11). CONCLUSIONS: The results of the study suggest that drain placement during open partial nephrectomy can safely be omitted, even in cases with violation of the collecting system.

Cisplatin-Based Chemotherapy for Testicular Germ Cell Tumors: Complication Rates of Peripheral versus Central Venous Administration.

OBJECTIVE: Despite the low local toxicity of the used agents, Cisplatin-based chemotherapy (CBP) for patients with testicular germ cell tumors (TGCT) is mostly delivered via a central venous access (CVA). Since 2008, CBP is given peripherally in our hospital. METHODS: Medical reports of TGCT patients who received CBP between September 1991 and August 2014 were evaluated. Complications regarding the way of administration (CVA vs. peripheral venous catheter [PVC]) were classified according to the Common Terminology Criteria of Adverse Events. The complication rates were compared using chi square test and propensity score matching. RESULTS: During 288 cycles in 109 patients, 85 complications (29.5%) were observed with similar rates for overall (PVC 31.3%, CVA 29.9%; p = 0.820) and grade I complications (21.3%, 25.4%; p = 0.470). More grade II complications were observed in the PVC group (10.0 vs. 1.5%; p < 0.001). Grade III complications requiring invasive treatment were found only in the CVA group (3.0%; p = 0.120). Using propensity score matching, no differences in overall (p = 0.950), grade I (p = 0.540) and grades II/III (p = 0.590) complications were seen. CONCLUSION: The peripheral and central administration of CBP has similar overall complication rates. Despite more grade II complications, the peripheral administration of CBP is a safe alternative for TGCT patients. Additionally, no severe grade III complications occurred.

ZIRK-Technique: Zero Ischemia Resection in the Kidney for High-Risk Renal Masses: Perioperative Outcome.

OBJECTIVES: This study evaluates the feasibility and safety of open-partial nephrectomies in the ZIRK-technique (Zero Ischemia Resection in the Kidney) for renal masses with high-risk anatomical features--objectified by the PADUA score. METHODS: We identified 40 consecutive cases of partial nephrectomies performed without clamping of the renal artery in our department of urology. Retrospective analysis of the preoperative CT or MRI scans showed 27 cases with a PADUA score ≥8, of which 15 cases had a score ≥10. Cases were in particular assessed regarding operation time (ORT), estimated blood loss (EBL), surgical margins and postoperative complications using the Clavien classification. RESULTS: The mean age of the study population was 67.6 years with an average BMI of 26.8 kg/m2. The mean ORT was 1:46 with an average EBL of 521 ml. Clavien grade II complications were observed seven times, while 3 patients had a grade IIIa complication. Despite complex and adverse location of the tumors, nephron-sparing surgery without ischemia could be performed with negative surgical margins for all cases. EBL, transfusion rate and complication were considerably more frequent in high-risk tumors. CONCLUSION: Highly complex renal tumors, PADUA ≥10, can be resected in ZIRK-technique with good operative outcome and a low complication rate.

Radiation exposure during endourologic procedures using over-the-table fluoroscopy sources.

BACKGROUND AND PURPOSE: Fluoroscopy is used daily by endourologic surgeons worldwide without knowledge of received radiation doses. We wanted to assess the radiation exposure of endourologic surgeons by frequently performed endourologic interventions with an over-the-table x-ray system. PATIENTS AND METHODS: In this prospective single-center study, 235 endourologic interventions in 188 patients from April to September 2010 were included. Sixty-seven ureteral stent placements (USP), 51 ureteral stent changes (USC), 67 percutaneous stent changes (PSC), 11 percutaneous nephrolithotomies (PCNL), and 39 ureterorenoscopies (URS) were performed by 12 surgeons. The surgeon`s radiation exposure was measured with one thermoluminescent dosimeter (TLD) at the forehead and one at the ring finger. TLDs were analyzed at a central institute. The radiation dose detected at the forehead was counted as representative for the lens of the eye and the thyroid. RESULTS: Mean patient age was 60.6 (± 18.8) years. Analysis of the TLD showed the following average values at the forehead for each intervention: USP and USC 0.04 mSv; PSC 0.03 mSv; PCNL 0.18 mSv; URS 0.1 mSv. Average finger values are: USP 0.13 mSv; USC 0.21 mSv; PSC 0.20 mSv; PCNL 4.36 mSv; URS 0.15 mSv. CONCLUSIONS: This report evaluates surgeons' radiation exposure by everyday endourologic interventions of different complexity. Most can be performed with an over-the-table x-ray system without exceeding statutory limits. Especially for PCNL, surgeons should consider possible protective action.

Prolonged cold ischemia time for laparoscopic partial nephrectomy with a new cooling material: Freka-Gelice--a comparison of four cooling methods.

BACKGROUND AND PURPOSE: It is well known that hypothermia protects renal tissue from ischemic damage. So far, no standardized cooling method for laparoscopic surgery has been established. The traditionally used cooling method during open partial nephrectomy (OPN) is crushed ice applied around the kidney; for laparoscopic use, transarterial and transureteral perfusion cooling are described. We compared these three cooling methods with Freka-Gelice (FG), a new gel-like cooling material, and present our initial preliminary results in an ex-vivo porcine model. MATERIALS AND METHODS: To prove cooling effectiveness, FG was compared with superficial crushed ice (NaCl-ice), with transureteral perfusion (TUP), and with transarterial perfusion (TAP) cooling in ex-vivo porcine kidneys. The temperature decrease over 120 minutes and practical application were evaluated. RESULTS: No significant difference was found for the mean value distribution at different time points for NaCl-ice and FG (P = 0.18). TUP and TAP showed insufficient temperature decrease. Mean temperatures for NaCl-ice and FG were 4.75 degrees C and 7.02 degrees C at 30 minutes, 0.72 degrees C and 2.47 degrees C at 60 minutes, and -0.19 degrees C and 2.35 degrees C at 120 minutes, respectively. FG was easy to use because of its gel-like consistence. CONCLUSION: TUP and TAP did not provide a fast and sufficient temperature decrease for renal hypothermia in this ex-vivo model. FG shows sufficient cooling qualities comparable with conventionally used NaCl-ice. Because of its gel-like consistence, FG can be used for laparoscopic partial nephrectomy, because insertion through a trocar is possible.

Effect of pulse energy, frequency and length on holmium:yttrium-aluminum-garnet laser fragmentation efficiency in non-floating artificial urinary calculi.

BACKGROUND AND PURPOSE: Holmium:yttrium-aluminum-garnet (Ho:YAG) laser lithotripsy is the standard lithotrite in ureteroscopy. We investigated the influence of pulse frequency, energy and length on the fragmentation efficiency of Ho:YAG laser lithotripsy in non-floating artificial stones in vitro. MATERIALS AND METHODS: Stone fragmentation efficiency of three different Ho:YAG laser devices were evaluated in vitro at different pulse energy (1.0 and 2.0 J) and frequency settings (5 and 10 Hz), resulting in a standardized output power of 10W, respectively. Where possible, pulse length was modified (350 vs 700 microsec). Each setting was performed with a 273 microm and a 365 microm fiber. Lithotripsy was conducted using non-repulsive stones consisting of soft stone (plaster of Paris) and hard stone composition (Fujirock type 4). RESULTS: Our results showed an increased stone disintegration efficiency at higher pulse energy (2.0 J/5 Hz vs 1.0 J/10 Hz) independently of two fiber diameters and stone types applied in this study (P < 0.05 in 18 of 20 groups). Similarly, reduction of the pulse length from 700 to 350 microsec resulted in a higher stone disintegration (P < 0.05 in 13 of 16 groups). This effect was most prominent when applied to soft stones. Higher fiber diameter was not constantly associated with an increase in stone disintegration. CONCLUSION: We demonstrate that an increase of pulse energy and a reduction of pulse length at a standardized output power of 10W can improve Ho:YAG laser fragmentation efficiency in vitro in nonfloating stones. These results may potentially affect clinical practice of Ho:YAG laser lithotripsy in impacted or large stones, when retropulsion is excluded.

120 W lithium triborate laser for photoselective vaporization of the prostate: comparison with 80 W potassium-titanyl-phosphate laser in an ex-vivo model.

PURPOSE: To evaluate the ablative and hemostatic properties of the recently introduced 120 W lithium triborate (LBO) 532 nm laser and compare the results against the conventional 80 W potassium-titanyl-phosphate (KTP) laser. MATERIALS AND METHODS: The ex-vivo model of the isolated blood-perfused porcine kidney was used to determine the ablation capacity, hemostatic properties, and coagulation depth of the GreenLight HPS laser system (American Medical System, Minnetonka, MN) that used an output power of 120 W. The results were compared with the KTP laser that used output power levels of 30 W, 50 W, and 80 W. Unperfused kidneys were weighed before and after 10 minutes of laser ablation in an area of 3 x 3 cm; the weight difference marked the amount of removed tissue. Bleeding was determined by the weight difference of a swab before and after it was placed on the bleeding surface for 60 seconds after ablating a surface area of 9 cm(2) on blood-perfused kidneys. RESULTS: With a tissue removal of 7.01 +/- 1.83 g after 10 minutes of laser ablation at 120 W, the LBO laser offered a significantly higher ablation capacity compared with 3.99 +/- 0.48 g reached with the conventional KTP laser at 80 W in the same time interval (P < 0.05). The bleeding rate was also significantly increased using the LBO at 120 W compared with the conventional device at 80 W (0.65 +/- 0.26 g/min vs 0.21 +/- 0.07 g/min; P < 0.05). The corresponding depths of the coagulation zones were 835 +/- 73 microm and 667 +/- 64 microm (P < 0.05), respectively. CONCLUSION: The 120 W LBO laser offers a significantly higher tissue ablation capacity compared with the conventional 80 W KTP laser. Because the increased efficacy of the device is accompanied by a higher bleeding rate and a slightly deeper coagulation zone, the user has to select the appropriate output power levels carefully for a safe and efficient treatment. Nevertheless, the bleeding rate compared with previous studies of transurethral resection of the prostate is significantly reduced.

70 vs 120 W thulium:yttrium-aluminium-garnet 2 microm continuous-wave laser for the treatment of benign prostatic hyperplasia: a systematic ex-vivo evaluation.

OBJECTIVE: To evaluate the ablative and haemostatic properties of the recently introduced 120-W thulium:yttrium-aluminium-garnet (Tm-YAG) laser and to assess these results against those of the previously introduced 70-W Tm-YAG laser. MATERIALS AND METHODS: The ex-vivo model of the isolated blood-perfused porcine kidney was used to determine the ablation capacity, haemostatic properties and coagulation depth of a 2 microm continuous-wave Tm-YAG laser. The energy was delivered using a 550-microm and an 800-microm bare-ended fibre. The results of the recently introduced 120-W Tm-YAG were compared to the established 70-W device. Kidney tissue was embedded for histological evaluation. After staining (haematoxylin and eosin, H & E; and NADH) of the specimen, the coagulation zone and depth of the necrotic tissue layer were measured. RESULTS: With increased power output, the mean (sd) rate of vaporization of tissue increased, from 9.80 (3.03) g/10 min at 70 W to 16.41 (5.2) g/10 min at 120 W using the 550 microm fibre. The total amount of ablated tissue using the 800 microm fibre was lower than with the 550 microm fibre. With increasing power output the bleeding rate remained stable in either group. Tissue penetration remained shallow, even with increasing power output. In contrast to H&E staining, where the coagulation zone was measured, NADH staining showed an inner zone of necrotic tissue, again with no difference between the 70- and the 120-W Tm-YAG. CONCLUSION: The 120-W Tm-YAG offers significantly higher ablation rates than the 70-W device, and despite the increased rate of ablation with the 120-W Tm-YAG, the bleeding rate and depth of tissue penetration were comparable to those using the 70-W device.

New alternatives for laser vaporization of the prostate: experimental evaluation of a 980-, 1,318- and 1,470-nm diode laser device.

PURPOSE: Several diode laser systems were introduced in recent years for the minimal-invasive surgical therapy of benign prostate enlargement. We investigated the ablation capacities, hemostatic properties and extend of tissue necrosis of different diode lasers at wavelengths of 980, 1,318 and 1,470 nm and compared the results to the 120 W GreenLight HPS laser. METHODS: The laser devices were evaluated in an ex vivo model using isolated porcine kidneys. The weight difference of the porcine kidneys after 10 min of laser vaporization defined the amount of ablated tissue. Blood loss was measured in blood-perfused kidneys following laser vaporization. Histological examination was performed to assess the tissue effects. RESULTS: The side-firing 980 and 1,470 nm diode lasers displayed similar ablative capacities compared to the GreenLight HPS laser (n.s.). The 1,318-nm laser, equipped with a bare-ended fiber, reached a higher ablation rate compared to the other laser devices (each P < 0.05). A calculated 'output power efficiency per watt' revealed that the 1,318-nm laser with a bare-ended fiber reached the highest rate compared to the side-firing devices (each P < 0.0001). All three diode lasers showed superior hemostatic properties compared to the GreenLight HPS laser (each P < 0.01). The extend of morphological tissue necrosis was 4.62 mm (1,318 nm), 1.30 mm (1,470 nm), 4.18 mm (980 nm) and 0.84 mm (GreenLight HPS laser), respectively. CONCLUSION: The diode lasers offered similar ablative capacities and improved hemostatic properties compared to the 120 W GreenLight HPS laser in this experimental ex vivo setting. The higher tissue penetration of the diode lasers compared to the GreenLight HPS laser may explain improved hemostasis.

Does open stone surgery still play a role in the treatment of urolithiasis? Data of a primary urolithiasis center.

OBJECTIVE: The introduction and continuous development of percutaneous nephrolithotomy, the achievement of extracorporeal shock-wave lithotripsy, and the advancements in ureterorenoscopy have led to a revolution in the interventional management urolithiasis. The indications for open stone surgery have been narrowed significantly making it a second- or third-line treatment option. We report on patients undergoing open stone surgery for nephrolithiasis in our department during the last 10 years to examine our indications at a primary urolithiasis center and to determine the clinical situations in which open surgery is a reasonable alternative. PATIENTS AND METHODS: We reviewed all patients undergoing open stone surgery for upper urinary tract stones from 1997 until 2007 at the Department of Urology, University Hospital Mannheim. A retrospective chart analysis was performed on these patients to identify factors and indications for open stone surgery. Indications for stone surgery, type of surgery performed, stone complexity, anatomical abnormities present, and the residual stone burden were reviewed. RESULTS: During a 10-year period 26 open stone operations were performed in our high-volume center. Indications for open stone removal were complex stone mass with complete or partial staghorn stones, concomitant open surgery, nonfunctioning stone-bearing lower poles, the desire to facilitate future stone passages in cystine stone formers, multiple stones in peripheral calyces, and failed minimal invasive procedures. Procedures performed for stone removal included radial nephrotomies, extended pyelolithotomy, lower pole resection, partial nephrectomy, and ileum ureter replacement. Immediate stone-free rate after a single procedure was 69% (18/26 patients). CONCLUSIONS: Although today most stone cases can be handled by minimally invasive treatment, open stone surgery maintains a mandatory role in very selected cases. The most common indication in our series though was complex stones with a high stone burden especially in combination with anatomical variations.

Case report: loss of hernia mesh after simultaneous laparoscopic extraperitoneal lymphadenectomy, radical prostatectomy, and hernioplasty.

We present a case of prosthetic mesh hernia repair of a unilateral inguinal hernia following laparoscopic extraperitoneal pelvic lymph node dissection and radical prostatectomy. After an uneventful intraoperative and early postoperative period, the patient developed a lymphocele. This resulted in the detachment of the mesh from the abdominal wall, which necessitated its removal.

Magnetic resonance imaging as a technique for assessing noninvasive tissue ablation using high-intensity ultrasound: an experimental study.

BACKGROUND AND PURPOSE: As a form of noninvasive extracorporeal application, acoustic energy offers an alternative to nephron-sparing surgery for renal masses smaller than 4 cm. The availability of a reliable tool for monitoring the therapy is a prerequisite for safe and successful high-intensity focused ultrasound (HIFU) application. The aim of this study was to evaluate the morphologic visualization of HIFU lesions using MRI. MATERIALS AND METHODS: We used the ex vivo model of the isolated perfused porcine kidney. Treatment was performed using an experimental HIFU system. Complex lesions were induced in 10 kidneys. MRI was performed under constant perfusion of the kidneys. To determine the exact lesion size, we performed a fat-saturated, T1-weighted, volumetric interpolated breath-hold MRI sequence. For perfusion imaging, we used a three-dimensional fast low-angle shot sequence. Subsequently, the lesions were evaluated macroscopically. The width of the complex lesions was defined as x, the length as y, and the depth as z. RESULTS: The MRI scans showed good soft tissue contrast in all sequences. The mean difference for the width of the lesions was 0.2 +/- 1.1 mm; for lesion length and depth, it was 1.7 +/- 1.8 mm and 1.1 +/- 1.3 mm for lesion width, respectively. Statistical evaluation of the x values showed no significant difference between the macroscopic and the MRI data (P = 0.85). The y and z values, however, showed a statistically significant difference (P = 0.071). CONCLUSION: MRI could be a diagnostic tool for monitoring HIFU. Before this modality can be used under clinical conditions, further technical development is indispensable, especially with respect to reducing the measuring times.

Systematic evaluation of a recently introduced 2-microm 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.

Hemostatic properties of four devices for partial nephrectomy: a comparative ex vivo study.

PURPOSE: Laparoscopic partial nephrectomy (LPN) is a common minimally-invasive treatment modality for renal tumors, and achieving hemostasis during excision is a major challenge. The aim of our study was to investigate the hemostatic potential of four different devices for realizing this under standardized conditions. MATERIALS AND METHODS: LPN was performed on a standardized model of blood-perfused ex-vivo porcine kidneys. Each of the four devices (Greenlight KTP laser, Habib Sealer, LigaSure, and SonoSurg) as well as a scalpel (for comparison) were used to perform 10 excisions with the renal artery and vein clamped, and another 10 were performed with no clamping. Treatment time (TT), blood loss (BL), and the ease of handling of the device were measured and histologic examination of the margins was carried out. RESULTS: In general, TT was faster and there was less BL with clamping than without in all cases. TT was shortest for the KTP laser (6.07+/-1.2 minutes; P<0.0001), followed by the LigaSure (8.78+/-0.42 minutes), the SonoSurg (15.9+/-1.28 minutes), and the Habib (21.7+/-3.4 min). The SonoSurg showed a significantly higher BL without clamping (66+/-6 ml, p<0.0001) but there were no significant differences between the other devices. With clamping, BL four all four devices was comparable (13+/-2 ml) and without statistical significance (p=0.5). TT was shortest for the KTP laser (3.27+/-0.55 min, p<0.0001) followed by the LigaSure (6.47+/-0.38 s), the SonoSurg (8.35+/-3 min) and the Habib (9.71+/-1.18 minutes). The excised surface was completely coagulated for all of the devices except for the SonoSurg. CONCLUSION: Our ex-vivo study suggests that hemostatic potential and the coagulative effect of all four devices is inadequate. Furthermore, none of the devices produced clean and sharp resection margins, which is a prerequisite for negative surgical margins.

Improvement in mortality and morbidity in transurethral resection of the prostate over 17 years in a single center.

BACKGROUND AND PURPOSE: Various improvements in the technique of transurethral resection of the prostate (TURP) have helped to reduce morbidity and mortality over the years. In this retrospective study, developments in the perioperative course in a single center were analyzed. PATIENTS AND METHODS: A retrospective chart analysis was performed on 399 patients undergoing TURP in our institution between 1987 and 1997, summarized as group 1, and 550 patients operated on between 1997 and 2004, summarized as group 2. Personal data, preoperative findings, intraoperative and postoperative complications, and outcomes in the two groups were compared. RESULTS: Average patient age, preoperative peak flow, residual volume, size of the prostate, and operation time did not differ statistically, whereas the amount of resected tissue was slightly higher in group 1 (30.1 g v 26.5 g). The mortality rate dropped from 0.5% in group 1 to 0 in group 2. Intraoperative bleeding necessitating transfusion (20.3% v 3.8%), capsule perforation (17.3% v 6.2%), and postoperative urinary-tract infections (37.1% v 6.2%) were significantly reduced in group 2. The incidence of TUR syndrome (2.0% v 1.6%) and severe anaesthesiology complications (1.8% v 0.9%) were only insignificantly lower in group 2. Postoperative bleeding, recatheterization, reintervention, and nonspecific complications remained unchanged, while the incidence of grade II or III stress incontinence and the postoperative hospital stay were reduced in group 2. CONCLUSIONS: Our study gives data on a contemporary TURP series and outlines a development toward fewer perioperative complications.

Newly developed mini-endoscope for diagnosis and follow-up of orthotopic bladder transitional-cell carcinoma in vivo.

BACKGROUND AND PURPOSE: Orthotopic models of bladder transitional-cell carcinoma (TCC) are indispensable to the development of new intravesical agents for the treatment of non-muscle-invasive disease. Visual inspection of induced tumors and normal urothelium is of crucial interest when evaluating growth patterns and the potential effects of instillation therapies. The aim of our study was to test the practicability of a newly developed mini-endoscope in terms of the benefit and reproducibility of repeated diagnostic cystoscopy in a rat model, thus mimicking standard procedures in patients. MATERIALS AND METHODS: The study group consisted of 24 Foxn(rnu) athymic nude rats. In 18 animals, a suspension of the human TCC cell line UMUC-3 was instilled into the urinary bladder after trypsinization. Six animals underwent bladder trypsinization only and served as a control group. Follow-up cystoscopy was performed weekly. A newly developed semirigid mini-endoscope (Karl Storz, Tuttlingen, Germany), 0.89 mm in diameter, was used. RESULTS: In total, 213 cystoscopies were performed. Each animal underwent at least seven procedures at weekly intervals over a period of 2 months. All tumors were detected by the mini-endoscope within 14 days of tumor-cell implantation. Cystoscopy provided visibility of the entire lower urinary tract (LUT), with the smallest detectable lesion being 0.5 mm in diameter. The regularly performed cystoscopy was tolerated without any significant procedure-related morphologic alterations in the LUT. CONCLUSIONS: The new mini-endoscope constitutes a practicable and reliable tool for diagnosis and regular follow-up cystoscopy in rats. This instrument can contribute to the preclinical development of experimental intravesical antitumor agents when used for regular evaluations of morphologic drug effects in vivo.

980-nm Diode laser: a novel laser technology for vaporization of the prostate.

OBJECTIVE: The wavelength 980 nm of a recently introduced diode laser system for treatment of benign prostatic enlargement offers a high simultaneous absorption in water and haemoglobin, and is postulated to combine high tissue ablative properties with a good haemostasis. METHODS: The Ceralas HPD150 diode laser system was evaluated in the well-established ex vivo model of the isolated blood-perfused porcine kidney to evaluate tissue ablation capacity and haemostatic properties at different generator settings. A histological examination of the ablated renal tissue followed. The results were compared with the reference standards transurethral resection of the prostate (TURP) and potassium-titanyl-phosphate (KTP) laser. RESULTS: The diode laser displays a higher tissue ablation capacity, reaching 7.24+/-1.48 g after 10 min, compared with the KTP laser (3.99+/-0.48 g; p<0.05), whereas only 30s are needed to resect the tissue in the same surface area using TURP, resulting in 8.28+/-0.38 g of tissue removal. With a bleeding rate of 0.14+/-0.07 g/min, the diode laser offers haemostatic properties equivalent to the KTP laser (0.21+/-0.07 g/min) and a significantly reduced bleeding compared with TURP (20.14+/-2.03 g/min; p<0.05). The corresponding depths of the coagulation zones are 290.1+/-46.9 microm for the diode laser, 666.9+/-64.0 microm for the KTP laser (p<0.05), and 287.1+/-27.5 microm for TURP. CONCLUSIONS: In the standardised ex vivo investigation, the 980-nm diode laser offers a higher tissue ablation capacity and similar haemostasis compared with the KTP laser. In comparison with TURP, both tissue ablation and bleeding are significantly reduced. The promising ex vivo results warrant further clinical investigation.

A new electromagnetic shock-wave generator "SLX-F2" with user-selectable dual focus size: ex vivo evaluation of renal injury.

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.