The Impact of Ureteral Access Sheath Use on the Development of Abnormal Postoperative Upper Tract Imaging after Ureteroscopy.

PURPOSE: Ureteral access sheaths are commonly used during ureteroscopy to facilitate stone removal, improve visibility and maintain low intrarenal pressures. However, the use of a ureteral access sheath can cause ureteral wall ischemia and ureteral tears, potentially increasing the risk of postoperative ureteral stricture and obstruction. We studied the impact of ureteral access sheath use on postoperative imaging studies. Secondary objectives included studying the impact of other intraoperative parameters on postoperative imaging studies. MATERIALS AND METHODS: A retrospective chart review was conducted of cases that underwent ureteroscopy for nephroureterolithiasis across 2 high volume institutions between January 2012 and September 2016. Patient demographics, cumulative stone size, operative time, use of ureteral access sheath, laser lithotripsy, basket extraction, preoperative ureteral stent and postoperative ureteral stent placement were extracted from the electronic medical record. Findings of followup renal ultrasound, kidney-ureter-bladder x-ray and/or computerized tomography at approximately 8 weeks after surgery were recorded. RESULTS: A total of 1,332 ureteroscopies were performed with 1,060 cases (79.6%) returning for routine upper tract imaging after ureteroscopy. Postoperative hydronephrosis was noted following 127 cases (12.0%). Factors predicting presence of hydronephrosis after ureteroscopy include lower body mass index (p=0.0016), greater cumulative stone size (p=0.0003), increased operative time (p <0.0001), preoperative ureteral stent (OR 1.49, p=0.0299) and postoperative ureteral stent placement (OR 6.43, p=0.0031). Postoperative hydronephrosis was not associated with use of ureteral access sheath, age, laser lithotripsy or basket extraction. CONCLUSIONS: Use of ureteral access sheath did not have a significant impact on development of postoperative hydronephrosis, suggesting ureteral access sheath is safe for use during ureteroscopy. Ureteral strictures remain rare following ureteroscopy, seen in only 1.0% of our cohort. With an observed prevalence of hydronephrosis of 12.0% on followup imaging at 8 weeks, routine upper tract imaging after ureteroscopy remains a valuable prognostic tool.

Supracostal access tubeless percutaneous nephrolithotomy: minimizing complications.

INTRODUCTION AND OBJECTIVE: Supracostal access in percutaneous nephrolithotomy (PCNL) may be avoided due to concern for thoracic complications. The objective of the study is to report the safety and efficacy of supracostal access utilizing a tubeless (stent only) PCNL technique. PATIENTS AND METHODS: Retrospective review of perioperative outcomes of 70 patients (76 renal units) who underwent a supracostal tubeless PCNL. No nephrostomy tubes were left. All patients had a 7F ureteral stent and Foley catheter placed. The nephrostomy sheath was removed with the patient held in end-expiration, and the incision closed. RESULTS: Median (IQR) age was 62 (48.3-67) years. Median stone size was 20 × 21 mm, and 14 (18%) patients had complete staghorn stones. The upper calyx was the site of access in 52 (68.4%) cases. Access was above the 12th and 11th rib in 63 (83%) and 12 (16%) cases, respectively. Median (IQR) length of stay was 30 (28-32) hours. Fifty (68.5%) patients had no residual fragments (< 2 mm) on postoperative imaging. Eight (11%) patients underwent an ancillary procedure (7 URS and 1 ESWL), with an additional seven patients becoming stone free after this procedure (78%). Thoracic complications occurred in two (2.6%) patients: one small pneumothorax, and one pleural effusion, both managed conservatively. Other complications occurred in nine patients (11.8%): bleeding requiring transfusion (1), fever (4), urinary retention (2), and syncope (2). CONCLUSION: Compared to historical controls, our approach to upper tract PCNL utilizing a nephrostomy tube-free approach resulted in an overall low thoracic complication rate and facilitated hospital discharge.

Multi-Institutional Validation of an OSATS for the Assessment of Cystoscopic and Ureteroscopic Skills.

PURPOSE: We evaluated the internal and construct validity of an assessment tool for cystoscopic and ureteroscopic cognitive and psychomotor skills at a multi-institutional level. MATERIALS AND METHODS: Subjects included a total of 30 urology residents at Ohio State University, Columbus, Ohio; Penn Presbyterian Medical Center, Philadelphia, Pennsylvania; and Mayo Clinic, Rochester, Minnesota. A single external blinded reviewer evaluated cognitive and psychomotor skills associated with cystoscopic and ureteroscopic surgery using high fidelity bench models. Exercises included navigation, basketing and relocation; holmium laser lithotripsy; and cystoscope assembly. Each resident received a total cognitive score, checklist score and global psychomotor skills score. Construct validity was assessed by calculating correlations between training year and performance scores (both cognitive and psychomotor). Internal validity was confirmed by calculating correlations between test components. RESULTS: The median total cognitive score was 91 (IQR 86.25, 97). For psychomotor performance residents had a median total checklist score of 7 (IQR 5, 8) and a median global psychomotor skills score of 21 (IQR 18, 24.5). Construct validity was supported by the positive and statistically significant correlations between training year and total cognitive score (r = 0.66, 95% CI 0.39-0.82, p = 0.01), checklist scores (r = 0.66, 95% CI 0.35-0.84, p = 0.32) and global psychomotor skills score (r = 0.76, 95% CI 0.55-0.88, p = 0.002). The internal validity of OSATS was supported since total cognitive and checklist scores correlated with the global psychomotor skills score. CONCLUSIONS: In this multi-institutional study we successfully demonstrated the construct and internal validity of an objective assessment of cystoscopic and ureteroscopic cognitive and technical skills, including laser lithotripsy.

Laparoscopic partial nephrectomy: six degrees of haemostasis.

OBJECTIVE: • To describe six steps for haemostasis and collecting system closure ('six degrees of haemostasis') that are reproducible and that minimize the two most concerning complications of laparoscopic partial nephrectomy: haemorrhage and urine leakage. METHODS: • A retrospective study of 23 consecutive laparoscopic partial nephrectomy cases performed by a single surgeon between 2005 and 2008 using the 'six degrees of haemostasis' was carried out. RESULTS: • There were no cases of intraoperative, postoperative or delayed bleeding. • There were no cases of urine leakage. CONCLUSION: • The 'six degrees of haemostasis' technique for laparoscopic partial nephrectomy described in the present study provides a reliable and reproducible method to reassure the surgeon of haemostasis and provide a decreased risk of urine leakage.

Sacrifice of accessory pudendal arteries in normally potent men during robot-assisted radical prostatectomy does not impact potency.

AIM: Whether or not sacrificing accessory pudendal arteries (APAs) during radical prostatectomy affects potency has been an ongoing source of concern. Herein, we present our potency results relative to sacrificing APAs in normally pre-potent men following robot-assisted radical prostatectomy (RARP). METHODS: The distribution of APAs and clinical characteristics were prospectively recorded in 200 consecutive patients undergoing RARP with a cautery-free technique. Sexual function was assessed using the International Index of Erectile Function 5-item questionnaire (IIEF-5). All APAs were sacrificed due to stapling the dorsal vein complex. MAIN OUTCOME MEASURES: Postoperatively, potency was defined by an affirmative answer to the following two questions: "Were erections adequate for penetration?" and "were the erections satisfactory?" Postoperative IIEF-5 scores and quality of erections (% of preoperative firmness: 0%, 25%, 50%, 75%, 100%) were also obtained. Subgroup analysis of patients age < or =65 years with IIEF-5 score of 22-25 was performed. RESULTS: Eighty patients (40%) had APAs. Preoperatively, there was no association with having an APA and normal/abnormal sexual function. Preoperatively, 58/200 were < or =65 years with self-administered IIEF-5 scores of 22-25. Postoperatively, 53/58 (91%) were potent at 24 months follow-up. Nineteen of 58 patients had a sacrificed APA; 39 patients had no APA. Eighteen of 19 (95%) patients with sacrificed APAs were potent vs. 35/39 (90%) with no APA present (P = 0.53). Multivariate analysis showed no significant correlation between sacrificing an APA and time of potency recovery, quality of postoperative erections (94% vs. 90% P = 0.80) or mean IIEF-5 score (22.4 vs. 20.8, P = 0.13). CONCLUSION: We found no correlation between the presence or absence of APAs and preoperative sexual function. Furthermore, after sacrificing all APAs, we found no correlation with potency return, time to return of potency, quality of erections, or mean IIEF-5 scores at 24 months.

Clinicopathologic analysis of renal cell carcinoma containing Intratumoral fat with and without osseous metaplasia.

BACKGROUND: There is minimal information regarding the prevalence of intratumoral adipose in renal cell carcinoma (RCC), and no study has assessed the impact of intratumoral adipose on the preoperative imaging diagnosis. The aim of this study was to investigate the prevalence and histopathologic characteristics of entrapped adipose with or without osseous metaplasia in RCC nephrectomy specimens and to determine if this finding impacted the preoperative imaging interpretation. METHODS: 704 RCC specimens were prospectively evaluated for entrapped adipose and osseous metaplasia (423 partial nephrectomies, 281 total nephrectomies; 327 pT1a, 377 ≥ pT1b; 510 clear cell, 119 papillary, 30 chromophobe, 22 clear cell papillary, 23 other). Imaging reports were obtained, and the presence of intratumoral fat or calcification and the radiologic diagnostic impression were recorded. RESULTS: 3% (n = 21) contained microscopically identified intratumoral adipose, with a similar frequency in the main histologic subtypes (p = 0.76). Mean metaplastic deposit size was 0.4 cm, mean deposit to capsule distance 0.2 cm, and 29% involved the tumor capsule. Histologically identified adipose was infrequently noted via imaging (13%), and only 1 case with histologically identified metaplasia had a radiologic diagnostic differential of angiomyolipoma (1/704, 0.1%). CONCLUSION: While intratumoral adipose and/or osseous metaplasia can be observed within RCC, it is extremely rare for the radiologic diagnostic impression to have been confounded by histologically identified entrapped adipose. Awareness that metaplastic deposits are usually near the tumor capsule and may be minute could help prevent errors in diagnosis or staging.

Comparative study of in vivo lymphatic sealing capability of the porcine thoracic duct using laparoscopic dissection devices.

PURPOSE: Sealing the lymphatic vessels during abdominal and pelvic surgery is important to prevent the leakage of lymphatic fluid and its resultant sequelae. To our knowledge we compared for the first time the quality of lymphatic sealing by each of 4 commonly used laparoscopic dissection devices. MATERIALS AND METHODS: A total of 12 domestic pigs were used to test dissecting devices, including monopolar scissors (Ethicon Endo-Surgery, Cincinnati, Ohio), Harmonic ACE Scalpel, LigaSure V, EnSeal and Trissector. A midline incision was made from mid sternum to umbilicus, the diaphragm was divided and the porcine thoracic duct was isolated. In all animals each device was used to seal an area of the duct and each seal was placed at least 2 cm from the prior seal. In group 1 the thoracic duct of 6 pigs was cannulated with a 5Fr catheter and the seal was subjected to burst pressure testing using a burst pressure measuring device (Cole-Parmer, Vernon Hills, Illinois). In the 6 pigs in group 2 each seal was immediately sent for histopathological evaluation. Specimens were given a score for the extent of cautery damage, including 0-none, 1-minimal, 2-moderate, 3-severe and 4-extreme. RESULTS: A total of 64 seals were created, of which 35 were subjected to burst pressure testing. Mean size of the thoracic duct was 2.6 mm. No acute seal failures were observed with any bipolar device or the harmonic shears. However, 2 immediate failures (33%) were seen with monopolar scissors. Mean burst pressure for monopolar scissors, Harmonic ACE Scalpel, LigaSure V, EnSeal and Trissector was 46 (range 0 to 165), 540 (range 175 to 795), 258 (range 75 to 435), 453 (range 255 to 825) and 379 mm Hg (range 175 to 605), respectively (p <0.05). Trissector, Harmonic ACE Scalpel and EnSeal generated seals with significantly higher burst pressure than that of monopolar scissors (p <0.05). Histopathological evaluation revealed that LigaSure caused less thermal damage than Trissector and EnSeal (p <0.05). CONCLUSIONS: Each device tested except monopolar scissors consistently produced a supraphysiological seal and should be suitable for sealing lymphatic vessels during laparoscopic surgery.

Long-term impact of a robot assisted laparoscopic prostatectomy mini fellowship training program on postgraduate urological practice patterns.

PURPOSE: Robot assisted laparoscopic prostatectomy has stimulated a great deal of interest among urologists. We evaluated whether a mini fellowship for robot assisted laparoscopic prostatectomy would enable postgraduate urologists to incorporate this new procedure into clinical practice. MATERIALS AND METHODS: From July 2003 to July 2006, 47 urologists participated in the robot assisted laparoscopic prostatectomy mini fellowship program. The 5-day course had a 1:2 faculty-to-attendee ratio. The curriculum included lectures, tutorials, surgical case observation, and inanimate, animate and cadaveric robotic skill training. Questionnaires assessing practice patterns 1, 2 and 3 years after the mini fellowship program were analyzed. RESULTS: One, 2 and 3 years after the program the response rate to the questionnaires was 89% (42 of 47 participants), 91% (32 of 35) and 88% (21 of 24), respectively. The percent of participants performing robot assisted laparoscopic prostatectomy in years 1 to 3 after the mini fellowship was 78% (33 of 42), 78% (25 of 32) and 86% (18 of 21), respectively. Among the surgeons performing the procedure there was a progressive increase in the number of cases each year with increasing time since the mini fellowship training. In the 3 attendees not performing the procedure 3 years after the mini fellowship training the reasons were lack of a robot, other partners performing it and a feeling of insufficient training to incorporate the procedure into clinical practice in 1 each. One, 2 and 3 years following the mini fellowship training program 83%, 84% and 90% of partnered attendees were performing robot assisted laparoscopic prostatectomy, while only 67%, 56% and 78% of solo attendees, respectively, were performing it at the same followup years. CONCLUSIONS: An intensive, dedicated 5-day educational course focused on learning robot assisted laparoscopic prostatectomy enabled most participants to successfully incorporate and maintain this procedure in clinical practice in the short term and long term.

Preliminary evaluation of a genitourinary skills training curriculum for medical students.

PURPOSE: Basic urology training in medical school is considered important for many medical and surgical disciplines. We developed a 2-day intensive genitourinary skills training curriculum for medical students beginning their clinical clerkship training years and evaluated the initial experience with this program. MATERIALS AND METHODS: All 94 third-year medical students at the University of California, Irvine were required to participate in a 5.5-hour genitourinary examination skills training program. The teaching course included 1.5 hours of didactic lecture and video presentation with questions and answers, followed by 5, 45-minute hands-on stations including male Foley catheter placement, female Foley catheter placement, testicular examination and digital rectal examination training with a standardized patient, virtual reality cystourethroscopy and, lastly, a urologist led tutorial of abnormal genitourinary findings. The students completed questionnaires before and after the course concerning their experience. At the end of the course the students rated the usefulness of each part of the curriculum and evaluated the faculty. In addition, they were required to complete a multiple choice examination that included 4 genitourinary specific questions. RESULTS: All 94 medical students completed the genitourinary skills training course. Before the course less than 10% of students reported comfort with genitourinary skills, including testicular examination (5%), digital rectal examination (10%), male Foley catheter placement and female Foley catheter placement (2%). Following the course the comfort level improved in all parameters of digital rectal examination (100%) and testicular examination, male Foley catheter placement and female Foley catheter placement (98%). The students rated in the order of most to least useful training 1) standardized patient for testicular examination and digital rectal examination teaching, 2) male Foley catheter placement and female Foley catheter placement training, 3) didactic lecture, 4) tutorial of abnormal genitourinary examination findings and 5) virtual reality cystourethroscopy. On the examination questions following the course 80% to 98% of the class answered each urology content question correctly. CONCLUSIONS: An intensive skills training curriculum significantly improved medical student comfort and knowledge with regard to basic genitourinary skills including testicular examination, rectal examination, and Foley catheter placement in the male and female patient. Further followup will be performed to determine the application of these skills during clinical clerkship rotations.

Preliminary study of virtual reality and model simulation for learning laparoscopic suturing skills.

PURPOSE: Repetitive practice of laparoscopic suturing and knot tying can facilitate surgeon proficiency in performing this reconstructive technique. We compared a silicone model and pelvic trainer to a virtual reality simulator in the learning of laparoscopic suturing and knot tying by laparoscopically naïve medical students, and evaluated the subsequent performance of porcine laparoscopic cystorrhaphy. MATERIALS AND METHODS: A total of 20 medical students underwent a 1-hour didactic session with video demonstration of laparoscopic suturing and knot tying by an expert laparoscopic surgeon. The students were randomized to a pelvic trainer (10) or virtual reality simulator (10) for a minimum of 2 hours of laparoscopic suturing and knot tying training. Within 1 week of the training session the medical students performed laparoscopic closure of a 2 cm cystotomy in a porcine model. Objective structured assessment of technical skills for laparoscopic cystorrhaphy was performed at the procedure by laparoscopic surgeons blinded to the medical student training format. A video of the procedure was evaluated with an objective structured assessment of technical skills by an expert laparoscopic surgeon blinded to medical student identity and training format. The medical students completed an evaluation questionnaire regarding the training format after the laparoscopic cystorrhaphy. RESULTS: All students were able to complete the laparoscopic cystorrhaphy. There was no difference between the pelvic trainer and virtual reality groups in mean +/- SD time to perform the porcine cystorrhaphy at 40 +/- 15 vs 41 +/- 10 minutes (p = 0.87) or the objective structured assessment of technical skills score of 8.8 +/- 2.3 vs 8.2 +/- 2.2 (p = 0.24), respectively. Bladder leak occurred in 3 (30%) of the pelvic trainer trained and 6 (60%) of the virtual reality trained medical student laparoscopic cystorrhaphy procedures (Fisher exact test p = 0.37). The only significant difference between the 2 groups was that 4 virtual reality trained medical students considered the training session too short compared to none of those trained on the pelvic trainer (p = 0.04). CONCLUSIONS: There is no significant difference between the pelvic trainer and virtual reality trained medical students in proficiency to perform laparoscopic cystorrhaphy in a pig model, although both groups require considerably more training before performing this procedure clinically. The pelvic trainer training may be more user-friendly for the novice surgeon to begin learning these challenging laparoscopic skills.

Retroperitoneal transdiaphragmatic robotic-assisted laparoscopic resection of a left thoracolumbar neurofibroma.

OBJECTIVE: Robotic technology has been used in a variety of surgical procedures for its 3D magnification and precision. Minimally invasive techniques have already become common in neurosurgery; however, robotic-assisted procedures in neurosurgery are still a relatively new frontier. This report describes the first use of robotic technology to resect a left thoracolumbar neurofibroma. CASE REPORT: A 19-year-old male with a family history of neurofibromatosis was diagnosed with a suspected 3-cm x 4-cm neurofibroma in the T12-L1 left paraspinal area. His only complaint was back pain requiring narcotic analgesics. He had no other findings on physical examination or laboratory/radiologic workup. METHODS: After consulting urologic robotic surgeons, it was agreed to use the da Vinci robot (Intuitive Surgical, Sunnyvale, CA) for the resection of this mass. Following retroperitoneal laparoscopic access, the urologic surgeons opened the diaphragm and began the initial mobilization of the mass laparoscopically. The robot was docked, and the neurosurgeon operated the robot at the console to resect the mass from its nerve origin. There were no complications, and the mass, a confirmed neurofibroma, was completely removed. The patient was discharged on postoperative day 2; his back pain resolved, requiring no analgesia by the end of the first postoperative week. CONCLUSION: This case provides early evidence that robotic assistance can be successfully used for the resection of a paraspinal neurofibroma.

Laboratory evaluation of laparoscopic vascular clamps using a load-cell device--are all clamps the same?

PURPOSE: The use of effective vascular clamps is key to successful laparoscopic partial nephrectomy. Based on our clinical experience the occlusive capabilities of vascular clamps appeared to be quite variable. We compared the occlusive force of currently available laparoscopic vascular clamps. MATERIALS AND METHODS: The jaw force of 3 laparoscopic vascular clamps (Aesculap(R), Klein Surgical Systems, San Antonio, Texas and Karl Storztrade mark) were measured by clamping a 2.2 mm compression load cell (Interface Advanced Force Measurement, Scottsdale, Arizona) in pound-force. The variables tested were handheld Satinsky, DeBakey and Storz clamps vs bulldog clamps, proximal, middle and distal application position, new vs used bulldog clamps and new vs used Satinsky handheld clamps. In addition, handheld clamps were tested according to the force generated by the notches in the locking mechanism. Force retention was also determined for all instruments after clamping a 20Fr latex rubber catheter for an hour. Finally, leak pressure studies were performed using a harvested porcine artery to determine the relationship between jaw force and leak pressure in mm Hg of bulldog and Satinsky handheld clamps using a pressure gauge (Cole-Parmer(R)). RESULTS: Handheld vascular clamps provided greater force than bulldog clamps. The proximal position closest to the hinge provided the greatest force across all instruments. Compared to new clamps the 2-year-old Klein Surgical Systems bulldog clamps showed a greater than 40% decrease in jaw force at all positions, whereas the 3-year-old Aesculap bulldog clamps decreased in jaw force by less than 9% at all positions. The 2-year-old Satinsky handheld clamps showed a decrease of 20%, 9% and 0% at the distal, middle and proximal jaw positions, respectively. Also, there was a positive correlation between force and the number of notches applied in handheld clamps. In addition, all instruments maintained jaw force after 1 hour of continuous clamping. Finally, leak pressure studies performed with used clamps showed that Klein Surgical Systems bulldog, Aesculap bulldog and Satinsky handheld clamps leaked at a pressure of 153 to 223, 465 to 795 and 1,500 to 2,600 mm Hg, respectively. CONCLUSIONS: Vascular clamps have varying occlusive forces according to clamp type, manufacturer, jaw and teeth characteristics, jaw clamping position and duration of use. However, across all clamps the jaw force was greatest at the proximal position. This is most important when applying laparoscopic bulldog clamps. In contrast, all handheld vascular clamps generated higher force than intracorporeal bulldog clamps. At 1 notch the handheld vascular clamps provided supraphysiological occlusion force regardless of position or manufacturer.

In vitro evaluation of nitinol urological retrieval coil and ureteral occlusion device: retropulsion and holmium laser fragmentation efficiency.

PURPOSE: Retropulsion of ureteral stones during laser lithotripsy may result in difficult and incomplete stone fragmentation. The Stone Cone nitinol urological retrieval coil and the NTrap nitinol ureteral occlusion device have been introduced into clinical practice to possibly limit stone retropulsion and enhance the efficiency of holmium laser (Convergent Laser Technologies, Alameda, California) stone fragmentation. MATERIALS AND METHODS: A total of 360 BegoStone Plus phantom stones (Bego USA, Smithfield, Rhode Island) of similar mass and weight were divided into 3 groups, including control, Stone Cone and NTrap. The groups were further subdivided according to fiber size (200 or 400 microm) and pulse width (350 or 700 microsec). These stones were placed in a horizontal pipette 12 mm in diameter, submerged in normal saline and disintegrated at laser settings of 1 J and 10 Hz continuously applied for 300 seconds. Retropulsion in cm and fragmentation efficiency with mass loss in mg were measured after treatment. RESULTS: The 2 devices were effective for preventing retropulsion. In the control group the mean +/- SD retropulsion distance using a 350-microsec pulse width with the 200 and 400 microm fibers was 18.4 +/- 5.9 and 14.1 +/- 4.6 cm, while it was 6.2 +/- 2.6 and 5.6 +/- 2.4, respectively, using the 700-microsec pulse width. There was a statistically significant higher loss of stone weight in the Stone Cone and NTrap experimental groups than in the control group (p <0.0001). However, there was no difference between the 2 experimental groups across all groups (p = 0.32). CONCLUSIONS: The Stone Cone and NTrap eliminated retropulsion and equally improved fragmentation efficiency. The maximum efficiency of fragmentation was seen using the 200 microm fiber at a 700-microsec pulse width.

Histological evaluation of cold versus hot cutting: clinical impact on margin status for laparoscopic partial nephrectomy.

PURPOSE: While most laparoscopic nephron sparing surgery is performed using cold scissors, energy based devices may also be used. A criticism of this approach has been the potential thermal destruction of the cellular architecture at the tumor margin, precluding the ability to accurately determine whether tumor cells are present. We clinically characterized the histological appearance of tumor margins excised with cold scissors, and bipolar and ultrasonic shears. MATERIALS AND METHODS: We evaluated 40 renal mass excisions performed by a total of 3 urologists at our institution between February 2003 and March 2007. There were 10 bipolar (5 mm LigaSure), 20 ultrasonic (Harmonic Scalpel) and 10 cold excisions. All slides were randomly evaluated twice by a single pathologist blinded to surgeon and excision method. Histological interpretation of the margin was scored as clear vs indeterminate. Variables, including margin fragmentation, artifact, extravascular blood clot, parenchymal hemorrhage, capillary congestion and vessel sealing, were assessed and scored on a scale of 0 to 3, that is 0--none, 1-1% to 25%, 2-26% to 50% and 3--greater than 50%. RESULTS: The pathologist was able to confidently identify cells at the margin as being malignant or benign in all cases. Histologically the ultrasonic scalpel demonstrated increased fragmentation and extravascular blood clotting compared with those of the other cutting methods (p <0.025 and <0.026, respectively). The ultrasonic scalpel also showed increased artifact depth compared to that of cold cutting (p <0.001). There were no statistical differences between the groups regarding margin artifact, parenchymal hemorrhage or capillary congestion. No statistical significance was observed in any variables between bipolar and cold cutting. CONCLUSIONS: Despite some degree of cellular damage the ability to determine whether cells at the margin were benign or malignant was not affected by using an energy based bipolar or ultrasonic device.

Minimally invasive management of upper tract malignancies: renal cell and transitional cell carcinoma.

This article focuses on the laparoscopic approaches to radical and partial nephrectomy for the managment of renal cell carcinoma and on the laparoscopic and endoscopic approaches for treating upper tract urothelial carcimoma. An in-depth discussion of treatment for transitional cell carcinoma is also presented.

High-frequency oscillatory ventilatory support during CT-guided percutaneous cryotherapy of renal masses.

PURPOSE: Computed tomography (CT)-guided percutaneous procedures are often made more difficult due to the movement of the kidney during respiration. Here we examine the use of high-frequency oscillatory ventilation (HFOV), which eliminates the movement of the kidney, potentially making cryoprobe access to the kidney simpler and possibly more efficient. METHODS: We compared seven CT-guided percutaneous procedures using a single cryoprobe and either standard mechanical ventilation (MV) (n=4) or HFOV (n=3). The variables studied included: total time of patient intubation, operative time, overall duration of interventional radiology (IR) suite time, change in hematocrit, narcotic use, and complications. The ease of the procedure was rated on a subjective scale from 1 to 3. RESULTS: The total intubation time remained nearly identical at 210 minutes for HFOV and 208 minutes for MV, but surgeon procedural time decreased by 31 minutes in the HFOV group (HFOV=99 minutes and MV=130 minutes) (P=0.40). Total IR time was 225 minutes for HFOV compared to 212 minutes for the MV group (P=0.63). There were no significant differences in the postoperative hematocrit, creatinine, or narcotic use between the two groups. There were no complications related to the procedure or anesthesia in either group. Both urology attending physicians and the interventional radiologist noted that the procedure seemed easier with HFOV. CONCLUSION: HFOV may shorten the actual procedural time required to perform cryoablation, likely due to the elimination of renal movement during the procedure, thereby facilitating targeting and access to the renal mass. In this initial experience, patients tolerated HFOV without incident, and the operating surgeons found it easier to perform the procedures.

Robotic versus standard laparoscopic partial/wedge nephrectomy: a comparison of intraoperative and perioperative results from a single institution.

PURPOSE: Laparoscopic partial/wedge nephrectomy, similar to laparoscopic radical prostatectomy, is a technically challenging procedure that is performed by a limited number of expert laparoscopic surgeons. The incorporation of a robotic surgical interface has dramatically increased the use of minimally invasive pelvic surgery such that robotic laparoscopic radical prostatectomy is commonly performed even by laparoscopically naïve surgeons. This analysis compares the outcomes of our initial experience with robot-assisted laparoscopic partial nephrectomy (RLPN) performed by an experienced open surgeon to that of standard laparoscopic partial nephrectomy (LPN) performed by two experienced laparoscopic surgeons. PATIENTS AND METHODS: We reviewed the medical records of 11 consecutive patients who underwent 12 standard LPNs (EMM, RVC) (one patient had two unilateral tumors) and 10 consecutive patients (representing the first 11 of such robotic procedures performed at our institution) who underwent 11 RLPNs (one patient had bilateral tumors managed in an asynchronous manner) (DKO). RESULTS: The mean tumor size was 2.3 cm (range 1.7-6.2 cm) for LPN and 3.1 cm (range 2.5-4 cm) for RLPN. The mean total procedure time was 289.5 minutes (range 145-369 min) for LPN and 228.7 minutes (range 98-375 min) for RLPN (P=0.102). The mean estimated blood loss was 198 mL (range 75-500 mL) for LPN v 115 mL (25-300 mL) for RLPN (P=0.169). The mean warm ischemia time was 35.3 minutes (range 15-49 min) in the LPN group and 32.1 minutes (range 30-45 minutes) in the RLPN group (P=0.501). CONCLUSIONS: Introducing a robotic interface for laparoscopic partial/wedge resection allowed a fellowship-trained urologic oncologist with limited reconstructive laparoscopic experience to achieve results comparable to those for laparoscopic partial/wedge resection performed by experienced laparoscopic surgeons. In this regard, the learning curve appears truncated, similar to that with robot-assisted laparoscopic prostatectomy.

Rapid communication: robot-assisted NOTES nephrectomy: initial report.

BACKGROUND AND PURPOSE: Natural Orifice Transluminal Endoscopic Surgery (NOTES) using the daVinci robot (Intuitive Surgical, Sunnyvale, CA) has never been applied to urologic surgery. Here we present our initial experience with a combined transvaginal and transcolonic, single-port, robot-assisted NOTES nephrectomy. METHODS: An acute experiment was performed in a female farm pig. A single 12-mm trocar was placed in the midline, and two 12-mm standard laparoscopic ports were placed into the abdomen via the vagina and the colon. The robotic ports were then telescoped into the 12-mm ports, and the daVinci S robot was docked. Dissection was performed using the Hot Shears and the ProGrasp instruments. The robotic camera was placed via the midline port and held by an assistant. Using the 12-mm transvaginal port, the renal artery and vein were divided separately with a vascular Endo GIA (US Surgical, Norwalk, CT) stapler. The kidney was placed into a 10-mm entrapment sack and removed intact via the vagina. RESULTS: Total operative time was 150 minutes. Estimated blood loss was less than 50 mL. No intraoperative complications occurred. CONCLUSION: A robot-assisted NOTES nephrectomy was accomplished in a porcine model using the daVinci S robot. Additional testing on survival animals is necessary to further explore this approach.

Holmium-YAG laser: impact of pulse energy and frequency on local fluid temperature in an in-vitro obstructed kidney calyx model.

During laser lithotripsy, energy is transmitted to both the stone and the surrounding fluid. As the energy is delivered, the temperature will rise. Temperatures ≥60 ° C can cause protein denaturation. The objective of this study is to determine the time it takes from body temperature (37°C) to 60°C at various laser power settings. A Flexiva TracTip 200 optical fiber was submerged alongside a negative temperature coefficient-type thermistor in 4 mL of saline in a glass test tube. A Lumenis VersaPulse Powersuite 100-W holmium:yttrium aluminum garnet laser was activated at 0.2- to 1.5-J pulse energies, 6- to 50-Hz frequencies, and 2- to 22.5-W average power. Temperature readings were recorded every second from 37°C until 60°C. Time and heating rate were measured. The procedure was repeated three times for each setting. Average time from 37°C to 60°C for settings (1) 0.2 J/50 Hz, (2) 0.6 J/6 Hz, (3) 1 J/10 Hz, and (4) 1.5 J/10 Hz was 60.3, 172.7, 58, and 43.3 s, respectively. Time from 37°C to 60°C decreased as frequency increased for every given pulse energy. Average heating rate increased proportionally to power from 0.06°C/s at 2 W to 0.74°C/s at 22.5 W. During laser lithotripsy, there is a rapid increase in the temperature of its surrounding fluid and temperatures ≥60 ° C may be reached. This could have local tissue effects and some caution with higher power settings should be employed especially where irrigation is limited. Further studies incorporating irrigation and live tissue models may aid to further define the risks.