Patrick Honeck

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.

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.

Three-dimensional laparoscopic imaging improves surgical performance on standardized ex-vivo laparoscopic tasks.

PURPOSE Conventional two-dimensional (2D) laparoscopy has been limited by the lack of depth perception and spatial orientation. This disadvantage may affect surgical performance, operative time, or morbidity. Depth perception, spatial resolution, and accuracy may be improved by three-dimensional (3D) vision. This study was designed to evaluate the effect of 3D imaging on the performance of novice and experienced laparoscopic surgeons executing standardized laparoscopic tasks in an ex-vivo setting. MATERIALS AND METHODS A 3D imaging system with a digital 3D full high definition (HD) and a 2D imaging with a conventional HDTV camera were used. A total of 10 laparoscopic experts and 10 novices were evaluated while performing standardized skill tasks in a pelvic trainer. Participants were divided into two groups working either with 2D or 3D imaging. The parameters measured were time until completion of each skill and total procedure time, number of losses of working material, number of missed grasps, and number of needed support. Statistical analysis was performed using the Wilcoxon test. RESULTS The results showed a significant difference in favor of the 3D system for the amount of missed grasps in the experts as well as the novice group (P<0.0001). A slightly significant difference was also seen for the loss of working materials (P=0.0381 and P=0.0693). The study is limited by its small sample size. CONCLUSION The 3D imaging system significantly improves spatial orientation and depth perception during laparoscopy under ex-vivo conditions.

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.

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.

New Endourologic Technology for Simultaneous Holmium:YAG Laser Lithotripsy and Fragment Evacuation for PCNL: Ex-Vivo Comparison to Standard Ultrasonic Lithotripsy

Percutaneous nephrolithotomy (PCNL) is a well established procedure and accepted as the standard of care for the treatment of large renal calculi. Since the introduction of the holmium:yttrium-aluminum-garnet (Ho:YAG) laser into clinical practice in 1990, it has been used successfully to treat various urologic conditions. Today it is the modality of choice for retrograde intracorporeal stone disintegration ureteroscopically, and has also been used successfully for PCNL. One disadvantage when using the Ho:YAG laser for disintegration of renal calculi is the need for graspers to extract fragments and the mobilization of fragments due to the lack of simultaneous suction. We present our experience with a Ho:YAG laser in combination with simultaneous suction in an in-vitro model using a new endourologic technique in comparison to conventional ultrasonic lithotripsy.

Conventional High Pressure versus Newly Developed Continuous-Flow Ureterorenoscope: Urodynamic Pressure Evaluation of the Renal Pelvis and Flow Capacity

PURPOSE We evaluated the pressure and flow relation of a newly developed continuous-flow ureterorenoscope (URS) in comparison with a common ureterorenoscope in an ex-vivo urinary tract model. MATERIALS AND METHODS Ureterorenoscopies were performed with the newly developed 10.5F continuous-flow URS with separate inflow and outflow channel and a conventional 10.5F URS with a combined inflow and outflow channel. The ex-vivo model consisted of complete urinary tracts of domestic pigs obtained freshly from the slaughterhouse. Both instruments were used in five urinary tracts, and six ureterorenoscopies were performed in each urinary tract. The pressure in the renal pelvis (RP) was measured during each procedure. Height of the irrigation solution above renal level and flow capacity were also documented. RESULTS The conventional URS showed a correlation of intrapelvic pressure and the height of the irrigation solution above renal level rising from 20+/-3.7 cm H(2)O at a solution level of 20 cm to a plateau pressure of 40+/-3.3 cm H(2)O with a distinct renal influx at a level of 50 cm. The maximum flow capacity at a solution level of 20 cm was 0.2 mL/min rising to a flow capacity of 0.5 mL/min at 40 cm above renal level. The maximum flow capacity for the continuous-flow URS was about 100 times higher, rising from 20 mL/min at a solution level of 20 cm to 70 mL/min at 40 cm above renal level. The intrapelvic pressure was 15+/-2.1 cm H(2)O at a solution level of 20 cm and did not exceed the physiologic renal pressure of 20 cm H(2)O even if the irrigation solution was at a height of 100 cm above renal level. CONCLUSION The newly developed continuous-flow URS provides a 100 times higher flow capacity while simultaneously preserving the physiologic pressure in the RP compared with the conventional URS. These characteristics will improve visibility and reduce retrograde stone manipulation, operative time, and complications under clinical conditions.

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.

Outcome of Sigmoid Compared to Ileal Orthotopic Bladder Substitution in Terms of Micturition and Defecation Parameters in an 8-Year Long-Term Follow-Up

Introduction: Various techniques have been described for orthotopic bladder substitution. Bladder substitution with sigma is rather classed as a useful alternative standby. We report the long-term results of sigmoid neobladder in comparison to ileal neobladder with respect to urodynamic and defecation parameters. Patients and Methods: We matched 10 patients with sigmoid neobladder (mean age 62.6 ± 10.9) and 10 patients with ileal neobladder (mean age 66.4 ± 10.2). Mean follow-up for sigmoid neobladder was 8.1 ± 2.1 years and 7.2 ± 1.9 years for the ileal neobladder. Each patient was evaluated by medical history, the SF-36 questionnaire, physical examination and urodynamics. Results: Bladder capacity differed significantly between both groups (sigmoid neobladder 619 ml, ileal neobladder 422 ml). Pressure showed a slight statistical difference (sigmoid neobladder 15 ± 3 cm H2O, ileal neobladder 18 ± 4 cm H2O). The defecation frequency varied significantly between the two groups (sigmoid neobladder 1.1/day, ileal neobladder 3.1/day, p < 0.0001). The SF-36 questionnaire showed no significant difference. Conclusion: Orthotopic bladder substitution with sigmoid segments has shown equivalent results compared to orthotopic ileal bladder substitution. The sigmoid neobladder is a useful alternative to the ileal neobladder.

Adenocarcinoma in Continent Anal Urinary Diversion: Is a Sigma Rectum Pouch a Surgical Option After Failed Ureterosigmoidostomy?

OBJECTIVE To report our experience of radical resection of secondary cancers after ureterosigmoidostomy. Ureterosigmoidostomy was the most common continent urinary diversion before the era of continent cutaneous diversion and neobladders, specifically in children. When performed for bladder exstrophy, patients will live with this kind of diversion for quite a long time. As a result, urologists will be confronted with patients presenting with an adenocarcinoma in their ureterosigmoidostomy. In most cases reported in the literature, an ileal conduit was used for urinary conversion. However, nowadays an ileal loop must not be the only solution for patients with a long life expectancy. MATERIALS AND METHODS Between 2004 and 2015, 6 patients were treated for an adenocarcinoma in their ureterosigmoidostomy. All patients underwent radical resection of the tumor-bearing sigmoid colon. After thorough preoperative informed consent concerning the choice of future urinary diversion, such as conversion to an ileal conduit, construction of a continent catheterizable pouch, or repeat continent anal diversion, 4 patients chose a repeat continent anal urinary diversion. RESULTS Up to this date, no complications or recurrences were seen after a median follow-up of 35 months. CONCLUSION In patients with secondary malignancy of the colon, radical resection of the tumor-bearing bowel segment is mandatory. A repeat continent anal urinary diversion appears to be a feasible alternative to secondary urinary diversion after resection of the tumor-bearing sigmoid colon. However, a longer follow-up is required to determine whether the risk of secondary malignancy remains unchanged, and whether the risk is increased or decreased.