Faculty Bibliography

PURPOSE/OBJECTIVE:To examine laser fiber passage capabilities through flexible ureterorenoscopes (fURSs) and to measure deflections and flow characteristics. METHODS:Cobra Vision; and Lithovue). Four laser fibers standard 200- and 273-μm (uncleaved and cleaved), sheath-coated and ball-tip fibers were attempted to pass through each fURS while deflected at 120°, 180°, maximum deflection, and maximum deflection with reduced 9-mm radius. Measurements included maximal (up/down) deflections and irrigation flow rates achieved with each fiber. RESULTS:Wolf Cobra Vision demonstrated minimal loss of deflections with mean differences of -2°/0° (p > 0.05) when loaded with the 200-μm fiber. The 273-μm fiber provoked utmost deflections that decline when loaded in Olympus URF-P5: mean differences of -52°/-35° (p < 0.001 for upward deflection). Of overall deflections, sheath-coated fiber induced least insult (p > 0.05), while standard 273-μm fiber incited maximum degradation (p < 0.00001). With few exceptions, sheath-coated and ball-tip fibers passed through all maximally deflected scopes. Uncleaved 200- and 273-μm fibers failed to pass through most maximally deflected fURS. However, cleaving their ends allowed 200- and 273-μm fiber to pass through all angles of deflections expect in the Olympus URF-P5 and Olympus URF-P5 and URF-V, respectively. The irrigation through all fURSs was significantly impaired (p < 0.00001). CONCLUSIONS:fURS deflection was least affected by sheath-coated fibers and most affected by the 273-μm fiber. Uncleaved 200- and 273-μm fibers showed least passage capabilities; while removing the ends, the fibers greatly facilitated their passage capabilities as much as the other fibers tested.

INTRODUCTION/BACKGROUND:The Spies™ system (Karl-Storz®) was introduced into digital ureteroscopy to improve endoscopic vision. To date, there is no data to either indicate which of the Spies modalities is better for improving diagnosis and treatment procedures, nor to compare the modalities in terms of image quality. The aim of this study was to evaluate and compare the image quality of five Spies™ modalities (SM) to the standard white light in an in-vitro model. MATERIALS AND METHODS/METHODS:Two standardized grids and 3 stones of different composition were recorded in white light and the 5SM (Clara, Chroma, Clara+Chroma), Spectra A and B) using 4 standardized aqueous scenarios. Twelve templates were done in order to simultaneously compare the same objective in the different modalities. Six urologists, five medical students, five urology residents, and five persons not involved with urology evaluated each video on a scale of 1 (very bad) to 5 (very good). RESULTS:Comparing white light to SM, subjects scored better the quality of Clara and Clara+Chroma than white light (p=0.0139 and p<0.05) and scored worse Spectra A and B (p=0.0005 and p=0.0023). When comparing Clara to the other SM, it was ranked equivalent to Clara+Chroma (p=0.67) and obtained a higher rank than Chroma, Spectra A and B (p<0.05, p=0.0001 and p=0.0001). In the multivariate analysis mean scores were higher among urologists. CONCLUSION/CONCLUSIONS:In all analyzed scenarios, the subjects ranked Clara and Clara+Chroma as the modalities with better image quality compared to white light.

INTRODUCTION/BACKGROUND:Miniaturization of instruments has changed the paradigms of percutaneous nephrolithotomy (PCNL). To date, however, few studies have analyzed the possible renal trauma generated by PCNL tract dilation. The purpose of this study is to evaluate and compare systematically the renal injury of all PNCL dilation techniques in pork kidneys (PK) and cadaveric kidney models (CK). MATERIAL AND METHODS/METHODS:Twelve dilation devices were tested (from 4.8 to 30 French (Fr)) including micro- and mini- PCNL kits, the Alken dilation set, 20 and 30 ATM balloons and the Amplatz set. Each device was tested six times in PK and CK. Morphologic analysis of tract defects of the different models and dilators were made measuring the longest axis and the area of renal parenchymal damage. RESULTS:(mean) larger than the instruments themselves. CONCLUSIONS:with dilations of 30 Fr. Overall, PK had significantly larger injuries than CK models.

INTRODUCTION/BACKGROUND:The aim of this study was to evaluate the acquisition of basic ureteroscopic skills with and without Roboflex Avicenna by subjects with no prior surgical training. MATERIAL AND METHODS/METHODS:simulator model. Participants were scored on their ability to perform or not two exercises, recording the time. In addition, the participants were evaluated on the quality of their performance for the following parameters: respect of the surrounding environment, flow of the operation, orientation, vision centering and stability. RESULTS:The first exercise was completed only by three and four out of five of students in Group 1 and Group 2, respectively. Stability with the scope was significantly more accurate in the first group compared with the second (P = 0.02). There were no differences in timing, flow or orientation between groups. Although not significant, a tendency of respecting the surrounding tissue and maintaining centered vision was perceived more in the first group. As for the second exercise, there were no differences between groups in regard of orientation, flow, respecting the surrounding tissue, stability or the ability of maintaining centered vision. Although not significant, the second group had a tendency of performing the exercise faster. CONCLUSIONS:simulator, by subjects with no prior surgical training, is similar.

INTRODUCTION:The costs of flexible ureterorenoscopes (fURSs) and their repair oblige the surgeon to know the proper handling of instruments. There is a lack of evidence in the literature about the safety distance that the laser fiber should have once out from the ureterorenoscope to avoid instrumental damages. MATERIALS AND METHODS:We performed an in vitro observational study. Seven fURSs were tested. The distance from the laser fiber tip and the fURS camera was measured at the first appearance on the endoscopic screen and when the fiber was reaching one-fourth of the screen. Second, to evaluate the impact of the holmium laser bubble according to different fiber distances, an assessment of the size and shape of the bubble created at the tip of the fiber with the laser activated was done, recording the images with a high-speed camera. RESULTS:The first appearance on the screen of the laser tip is different in different ureterorenoscopes. In all the ureterorenoscopes, we observed that when the laser fiber was at ¼ of the screen, the bubble was never touching the fURS tip. CONCLUSION:Even if there is a big limitation of this study due to the impossibility to measure and to evaluate the damage of the fURS tip surface, we observed that when the laser fiber tip reaches ¼ of the screen, the bubble generated by laser activation is never rebounding on the camera of the ureterorenoscope, preserving it from laser damages. We can define this position as the safety distance.

OBJECTIVE:To describe and discuss the feasibility and the use of apnea during retrograde intrarenal surgery (RIRS). MATERIALS AND METHODS:A discussion of the current literature about the different anesthesia techniques and the use of apnea to improve RIRS by avoiding renal movements over diaphragmatic excursion was performed. RESULTS:To date, there are no mentions in the literature about the use of apnea as a mechanism to facilitate this procedure that requires extremely precise laser use. A description of the feasibility of apnea during RIRS is described as a technical consideration and discussed. CONCLUSION:The use of apnea during RIRS has facilitated the procedure, avoiding renal movements, particularly in special cases where extremely precise maneuvers during laser use are required.

BACKGROUND:A ureteroileal anastomosis stricture (UAS) is one of the most frequent complications after radical cystectomy. Open surgical repair is the treatment of choice but is associated with morbidity. OBJECTIVE:To describe the efficacy and safety of laparoscopic management for benign secondary UAS. DESIGN, SETTING, AND PARTICIPANTS:A review was performed of the 11 initial procedures performed at our academic center from December 2010 to December 2014, with mean follow-up of 38 mo (range 12-169). Patients included had benign ureteroileal strictures longer than 1cm. SURGICAL PROCEDURE:A pure laparoscopic approach was systematically used, involving a two-step procedure for left and a one-step procedure for right ureteral stenosis. MEASUREMENTS:Perioperative data were collected and complications were assessed using the Clavien-Dindo grading system. Outcomes and follow-up data were analyzed. RESULTS AND LIMITATIONS:A descriptive statistical analysis was performed for 11 surgeries in ten patients. The median stricture length was 2.4cm. No conversion to open surgery was required. The mean blood loss was 180ml and the mean hospital stay was 10 d. Early complications included limited lymphorrhea (n=1), limited anastomotic leakage (n=2), and accidental descent of a ureteral catheter (n=1) that was replaced with radiologic intervention. The mean follow-up was 38 mo (range 12-169). No late complications were reported. After 1 yr of follow-up, six patients had good glomerular filtration rates, all patients were asymptomatic, and no stenotic relapses were detected. CONCLUSIONS:This laparoscopic technique for the management of benign secondary UAS is feasible, with good results and without long-term complications. This minimally invasive approach reduces the morbidity associated with open surgery while retaining good success rates. PATIENT SUMMARY:We describe a novel laparoscopic approach for patients with a ureteroileal anastomosis stricture after radical cystectomy to avoid the complications associated with open surgery. The surgery was found to be viable and safe with good long-term results.

INTRODUCTION/BACKGROUND:Shock wave lithotripsy (SWL) is the treatment of choice for most cases of renal lithiasis in children. Some cases, however, are refractory to SWL and may be associated with anatomic and metabolic changes or a large stone burden. In these circumstances, mini-percutaneous nephrolithotomy (mini-PCNL) is an option. OBJECTIVE:The aim was to assess the safety and efficacy of high-power holmium YAG (Ho:YAG) laser in mini-PCNL for staghorn calculi. PATIENTS AND METHODS/METHODS:The clinical records relating to 35 mini-PCNLs (Table) performed between January 2008 and December 2012 in 33 patients (27 boys and 6 girls; mean age 7 years, range 2-18 years) were retrospectively reviewed. Twenty-two (66.7%) of the patients had undergone a previous SWL (28.6% three sessions). The mini-PCNL puncture technique used involved fluoroscopic guidance with the C arm at 0-90° in the supine position. An 18F tract was used. Stone fragmentation was performed with a high-power Ho:YAG laser (Lumenis 100 W). RESULTS:Ten of the mini-PCNLs (28.6%) were right sided, and 25 were left sided (71.4%). Stones were located in the lower calyceal group in 64% of patients and in the renal pelvis in 50%. The mean stone size was 4.46 cm(2) (range 3-13.20 cm(2)). The number of stones varied between one and 20, and 83.3% were radiopaque. The laser was set at 70 W (range 50-100 W) (3.5 J/pulse with a frequency of 20 pulses/s). The mean surgical time was 150 min. In 78% of patients, complete stone clearance was achieved, and the overall stone-free rate rose to 85% when residual stones were treated with either SWL or retrograde intrarenal surgery. No perioperative complications were seen. DISCUSSION/CONCLUSIONS:There are few reports in the literature concerning the use of a high-power laser for treatment of complex stones and the few that do exist relate to adults have similar results, showing it to be highly effective and safe, with low morbidity. Some limitations of the present study must be acknowledged. It was retrospective and a relatively small number of patients were included. However, randomized prospective studies are required to confirm our findings and conclusions. CONCLUSION/CONCLUSIONS:In the pediatric population, mini-PCNL with high-power Ho:YAG laser is feasible and safe and represents the technique of choice for complex renal stones.

PURPOSE/OBJECTIVE:To prospectively evaluate the new Flexor©Parallel™ Rapid Release™ (Cook(®), Bloomington, IN, USA) access sheath (UAS) which allows the use of a single wire to serve as both safety and working guide. MATERIALS AND METHODS/METHODS:Between June and September 2014, adult patients from five European centers who underwent flexible ureteroscopy (fURS) for therapeutic and diagnostic purposes were included. The 12/14Fr Flexor©Parallel™ UAS was evaluated. Data were collected and examined by both univariate and multivariate analyses. The UAS material and usage characteristics were rated per case by the surgeons on a scale from very bad to very good. RESULTS:In total, 134 UASs were used in 67 male and 67 female patients. Fifty percent of ureters (67 patients) were pre-stented. Ninety percent of the procedures were therapeutic. The overall successful insertion rate was 94 %. Pre-stenting status was the only independent factor for a successful access sheath insertion: 98.5 % of the pre-stented patients had a successful UAS placement vs. 82 % of non-pre-stented (p = 0.001, C.I. 95 %: 1.2). Evaluation of the material and radiopacity was considered very good in over 90 % of cases. Release of the guidewire, hydrophilic coating, gliding of the endoscope and repeatability were considered very good in over 80 %. There were two (1.4 %) UAS malfunctions and one submucosal lesion reported. CONCLUSIONS:The use of the Flexor©Parallel™ Rapid Release™ (Cook(®), Bloomington, IN, USA) with usage of a single guidewire in a prospective multicentric scenario was clinically applicable in the majority of cases. Pre-stenting increased the chance of a successful insertion from 82 to 98.5 %.