Corollos S. Abdelshehid

Validation, Correlation, and Comparison of the da Vinci Trainer™ and the da Vinci Surgical Skills Simulator™ Using the Mimic™ Software for Urologic Robotic Surgical Education

PURPOSEnVirtual reality simulators with self-assessment software may assist novice robotic surgeons to augment direct proctoring in robotic surgical skill acquisition. We compare and correlate the da Vinci Trainer™ (dVT) and da Vinci Surgical Skills Simulators (dVSSS) in subjects with varying robotic experience.nnnMATERIALS AND METHODSnStudents, urology residents, fellows, and practicing urologists with varying robotic experience were enrolled after local institutional review board approval. Three virtual reality tasks were preformed in sequential order (pegboard 1, pegboard 2, and tubes)-initially on the dVSSS and then on the dVT. The Mimic™ software used on both systems provides raw values and percent scores that were used in statistical evaluation. Statistical analysis was performed with the two-tailed independent t-test, analysis of variance, Tukey, and the Pearson rank correlation coefficient where appropriate.nnnRESULTSnThirty-two participants were recruited for this study and separated into five groups based on robotic surgery experience. In regards to construct validity, both simulators were able to differentiate differences among the five robotic surgery experience groups in the tubes suturing task (p≤0.00). Sixty-seven percent (4/6) robotic experts thought that surgical simulation should be implemented in residency training. The overall cohort considered both platforms easy to learn and use.nnnCONCLUSIONSnAlthough performance scores were less in the dVT compared with the dVSSS, both simulators demonstrate good content and construct validity. The simulators appear to be equivalent for assessing surgeon proficiency and either can be used for robotic skills training with self-assessment feedback.

Third Prize: Flank Position Is Associated with Higher Skin-to-Surface Interface Pressures in Men Versus Women: Implications for Laparoscopic Renal Surgery and the Risk of Rhabdomyolysis

BACKGROUND AND PURPOSEnThere have been several reports of rhabdomyolysis occurring after prolonged laparoscopic procedures in the flank position. Accordingly, we evaluated interface pressures between the skin and three commonly used operating room table surfaces. The aim of our study was to determine if pressure changes could be related to body mass index (BMI), sex, position, and/or the table surface material.nnnPATIENTS AND METHODSnTen men and 10 women were grouped according to BMI <25 or >or=25, with five participants in each group. Subjects were placed in the left lateral decubitus position with the operating table flat, half flexed, fully flexed, half flexed with the kidney rest elevated, and fully flexed with the kidney rest elevated. Interface pressures were recorded, using an X-Sensor pressure sensing mat, for 5-minute periods in each of the described positions on each surface.nnnRESULTSnSex and BMI were statistically significant predictors of increased pressures (P= 0.0042 and 0.0402, respectively). The parameter estimate for the difference between men and women was 4.63 mm Hg (P= 0.0002), and the difference for BMI >or= 25 compared with <25 was also significant (P < 0.0209). Full table flexion (50-degree) produced significantly higher pressures than both flat (P= 0.0001) and the half-flexed (25-degree) position (P < 0.0001). Positions with the kidney rest elevated were associated with significantly higher pressures than without elevation (P < 0.0001). With regard to the surface used, egg crate provided lower pressures than gel pads (P= 0.0117).nnnCONCLUSIONnWomen have significantly lower interface pressures when compared with men. BMI >or= 25 also increases interface pressures. The use of the kidney rest is associated with markedly increased pressure; use of a half-flexed position is preferable to a full-flexed position. These data have implications for patient positioning and identification of persons at risk for rhabdomyolysis during laparoscopic renal surgery.

High-Fidelity Simulation-Based Team Training in Urology: Evaluation of Technical and Nontechnical Skills of Urology Residents During Laparoscopic Partial Nephrectomy

INTRODUCTIONnThe use of low-risk simulation training for resident education is rapidly expanding as teaching centers integrate simulation-based team training (SBTT) sessions into their education curriculum. SBTT is a valuable tool in technical and communication skills training and assessment for residents. We created a unique SBTT scenario for urology residents involving a laparoscopic partial nephrectomy procedure.nnnMATERIALS AND METHODSnUrology residents were randomly paired with a certified registered nurse anesthetists or an anesthesia resident. The scenario incorporated a laparoscopic right partial nephrectomy utilizing a unique polyvinyl alcohol kidney model with an embedded 3cm lower pole exophytic tumor and the high-fidelity SimMan3G mannequin. The Urology residents were instructed to pay particular attention to the patients identifying information provided at the beginning of the case. Two scripted events occurred, the patient had an anaphylactic reaction to a drug and, after tumor specimen was sent for a frozen section, the confederate pathologist called into the operating room (OR) twice, first with the wrong patient name and subsequently with the wrong specimen. After the scenario was complete, technical performance and nontechnical performance were evaluated and assessed. A debriefing session followed the scenario to discuss and assess technical performance and interdisciplinary nontechnical communication between the team.nnnRESULTSnAll Urology residents (n = 9) rated the SBTT scenario as a useful tool in developing communication skills among the OR team and 88% rated the model as useful for technical skills training. Despite cuing to note patient identification, only 3 of 9 (33%) participants identified that the wrong patient information was presented when the confederate pathologist called in to report pathology results.nnnCONCLUSIONnAll urology residents rated SBTT sessions as useful for the development of communication skills between different team members and making residents aware of unlikely but potential critical errors in the OR. We will continue to use SBTT as a useful method to develop resident technical and nontechnical skills outside of the high-risk operating environment.

In Vitro and In Vivo Comparison of Optics and Performance of a Distal Sensor Ureteroscope Versus a Standard Fiberoptic Ureteroscope

BACKGROUND AND PURPOSEnRecent advances in distal sensor technologies have made distal sensor ureteroscopes both commercially and technically feasible. We evaluated performance characteristics and optics of a new generation distal sensor Flex-X(C) (X(C)) and a standard flexible fiberoptic ureteroscope Flex-X(2) (X(2)), both from Karl Storz, Tuttlingen, Germany.nnnMATERIALS AND METHODSnThe ureteroscopes were compared for active deflection, irrigation flow, and optical characteristics. Each ureteroscope was evaluated with an empty working channel and with various accessories. Optical characteristics (resolution, grayscale imaging, and color representation) were measured using United States Air Force test targets. We digitally recorded a renal porcine ureteroscopy and laser ablation of a stone with the X(2) and with the X(C). Edited footage of the recorded procedure was shown to different expert surgeons (n=8) on a high-definition monitor for evaluation by questionnaire for image quality and performance.nnnRESULTSnThe X(C) had a higher resolution than the X(2) at 20 and 10 mm 3.17 lines/mm vs 1.41 lines/mm, 10.1 vs 3.56, respectively (P=0.003, P=0.002). Color representation was better in the X(C). There was no difference in contrast quality between the two ureteroscopes. For each individual ureteroscope, the upward deflection was greater than the downward deflection both with and without accessories. When compared with the X(2), the X(C) manifested superior deflection and flow (P<0.0005, P<0.05) with and without accessory present in the working channel. Observers deemed the distal sensor ureteroscope superior in visualization in clear and bloody fields, as well as for illumination (P=0.0005, P=0.002, P=0.0125).nnnCONCLUSIONSnIn this in vitro and porcine evaluation, the distal sensor ureteroscope provided significantly improved resolution, color representation, and visualization in the upper urinary tract compared with a standard fiberoptic ureteroscope. The overall deflection was also better in the X(C), and deflection as well as flow rate was less impaired by the various accessories.

LapED® 4-In-1 Silicone Training Aid for Practicing Laparoscopic Skills and Tasks: A Preliminary Evaluation

OBJECTIVEnWe developed a simple, inexpensive model to simulate four reconstructive laparoscopic procedures: pyeloplasty, vesicourethral anastomosis, bladder injury repair, and partial nephrectomy.nnnMATERIALS AND METHODSnLiquid silicone was applied in layers to a mold to create the 4-in-1 model. A questionnaire evaluating its face and content validity was distributed to postgraduate urologists participating in a mini-residency program at the University of California-Irvine (UCI), and in the 2006 American Urological Association Hands-On course on reconstructive laparoscopic pyeloplasty.nnnRESULTSnA total of 56 postgraduate urologists used the model and completed an evaluation questionnaire. Ninety-four percent (51/54) and 96% (48/50) agreed that the model was helpful for practicing laparoscopic pyeloplasty and urethrovesical anastomosis, respectively. Urologists who were experienced in either performing laparoscopic pyeloplasty (n = 6) or robot-assisted and/or laparoscopic prostatectomy (n = 11) would recommend this model to surgeons in training. Overall, 94% (48/51) and 96% (50/52) of the respondents would recommend this model for postgraduate surgeons and residents, respectively.nnnCONCLUSIONnWe present a versatile model for practicing laparoscopic and robotic suturing and knot-tying skills in four reconstructive urologic procedures. Our results support the face and content validity of this model for performing pyeloplasty and vesicourethral anastomoses.

The ‘buoy’ stent: evaluation of a prototype indwelling ureteric stent in a porcine model

To assess a prototype ureteric ‘buoy’ stent with a 10u2003F upper body tapering to a 3F tail, developed to potentially reduce stent‐related irritative symptoms while providing an adequate mould for healing after endopyelotomy.

Comparison of Healing after Cystotomy and Repair with Fibrin Glue and Sutured Closure in the Porcine Model

PURPOSEnWe compared healing after laparoscopic cystotomy using fibrin glue, sutures, or a combination to determine whether fibrin glue can obviate the need for sutures and whether there is any detriment when glue is used in the presence of sutures.nnnMATERIALS AND METHODSnIn 24 Yorkshire pigs, a 3.5 cm vertical cystotomy was created laparoscopically and repaired as follows: Group 1--no closure; group 2--fibrin glue closure; group 3--suture repair; group 4--combined fibrin glue and suture repair. All animals had a Foley catheter for 1 week. In each group, three animals were harvested at 1 week (acute) and three animals were harvested at 6 weeks (chronic).nnnRESULTSnAcute: Group 1--all pigs had an unhealed defect that leaked when evaluated by cystography. Groups 2, 3, 4--mean leak pressures were 80, 97, and 60 cm H(2)O (P = 0.36), respectively. Mean bladder capacity was not significantly different between groups. Chronic: No leakage seen on a cystogram at 1 week; at 6 weeks, bladders were filled at > or =95 to 100 cm H(2)O without leakage. Histologically, there was more inflammation in the acute group v chronic group pigs. In the acute group pigs repaired with glue or suture + glue, there was more inflammation and less epithelial continuity than in the suture alone group. At 6 weeks, there was no difference between groups.nnnCONCLUSIONnFibrin glue provoked an intense inflammatory response that might have delayed healing acutely, resulting in a lower burst pressure in both scenarios in which it was used (i.e., alone or in combination with sutures). However, by 6 weeks, there did not seem to be any difference between groups either clinically or histopathologically.

Tracking and assessment of technical skills acquisition among urology residents for open, laparoscopic, and robotic skills over 4 years: is there a trend?

BACKGROUND AND PURPOSEnTracking the progression of technical skill acquisition during urology residency training is an essential yet challenging task that has been mostly based on anecdotal and subjective performance assessment. We evaluated five surgical tasks used at our institution to assess skill acquisition among residents over 4 consecutive years in an effort to determine appropriate skill testing for resident proficiency relative to level of training for future performance testing.nnnMETHODSnUrology residents were tested yearly throughout the course of their residency with five surgical tasks in an open, laparoscopic, and robotic format. The five tasks were: (1) rings on a peg, (2) thread the rings, (3) cut the line, (4) hexagonal suturing, and (5) suture and knot tying. Evaluation was performed by a trained instructor to assess quantity and quality of the skill task performance.nnnRESULTSnThe highest scores were obtained on all open tasks regardless of training level. Residents performed second best on robotic and lowest on the laparoscopic skill tasks. The score difference among surgery platforms was statistically significant P<0.0005 across all tasks. It was Tasks 2 and 5, however, that showed a statistically significant difference in overall quantity×quality score between different postgraduate year (PGY) residents (P=0.03 and P=0.02). In addition, the quantity score for Task 5 also showed a statistically significant difference among PGY residents (P=0.04). There was no statistically significant difference in time to perform tasks among PG years.nnnCONCLUSIONSnThe high-level Tasks 2 and 5 were the most useful in differentiating different levels of skill task competency among urology residents and appear to be most useful in assessing the degree of improvement among residents during training. These tasks have subsequently been worked into our institutions testing curriculum.

In vitro evaluation of scopesafe fibers and the scope guardian sheath in prevention of ureteroscope endolumenal working damage

BACKGROUND AND PURPOSEnUreteroscope breakage is commonly related to laser fiber damage. Often, the damage is mechanical and not energy related. As such, we evaluated a novel laser fiber and sheath system in preventing mechanical ureteroscope damage during fiber insertion.nnnMATERIALS AND METHODSnWe assessed 200-μm/272/3-μm laser fibers with the laser sheath in a flexible ureteroscope. Diminishment of active deflection and irrigation flow rates were compared with a standard laser fiber alone. Eight nonassembled working channel components were tested in a 0-degree/90-degree/210-degree deflection model. After insertion cycles, external and endolumenal damage to the working channel were classified. We also tested the sheath system in a 0-degree/90-degree/210-degree deflection model for fiber failure and laser damage.nnnRESULTSnIn all test trials with the sheath and for standard laser fibers in the 0-degree model, there were no channel perforations or damage. With standard laser fibers, in the 210-degree model, superficial scratches and demarcated abrasions were visible after 10 and 60 to 70 insertions for the 273-μm laser fiber and after 30 insertions (superficial scratches) for the 200-μm laser fiber. In the 90-degree model, superficial scratches occurred after 20 insertions for the 273-μm fibers and after 40 insertions for the 200-μm laser fibers. No demarcated abrasions were seen after 100 insertions. In the 210-degree model, there was one perforation with the 272-μm fiber, but none with 200-μm fiber. There were no fiber failures with sheath use; however, the sheath did not prevent laser energy damage. The laser sheath resulted in a 4.7-degree/3.8-degree (1.2%/1.5%) diminishment in deflection (up/down) for the 200u2009μm and a 3.5-degree/4.3-degree (1.8%/1.5%) diminishment for 272-μm laser fiber compared with standard 200/272-μm laser fiber. Irrigation flow was diminished with the sheath on both the 200-μm and 272-μm laser fiber by 28.7% and 32.6%, respectively.nnnCONCLUSIONnThe Scope Guardian Sheath prevented mechanical working channel damage with minimal diminishment of deflection and irrigation flow.

Genitourinary Exam Skills Training Curriculum for Medical Students: A Follow-up Study of Comfort and Skill Utilization

PURPOSEnWe developed a genitourinary skills training (GUST) curriculum for incoming third year medical students (MS3) and performed a follow-up study of comfort with and utilization of these skills.nnnMATERIALS AND METHODSnGUST consisted of a didactic lecture followed by skills sessions including standardized patient testicular examination (TE) and digital rectal examination (DRE), male and female Foley catheter (MFC and FFC) placement training, suture-knot tying, and a faculty-directed small group learning session. Precourse and postcourse, and 6 and 18 months after the course, MS3 rated comfort with each skill (Likert scale 0-5), and quantified skill usage. Results were compared with 4th year students (MS4) who had not undergone GUST.nnnRESULTSnParticipants were 281 MS3 GUST students and 44 MS4. Post-GUST, mean comfort on a Likert scale (0=uncomfortable) increased for all four skills (88.2%-96.9% vs 8.3%-18.5%, P<0.0001). This was maintained at the 6-month and 18-month follow up time points (P<0.0001). At 18 months, MS3 trended toward higher comfort with TE compared with MS4 (74 vs 54%, P=0.068), while with the other skills, both groups showed equal comfort. MS4 learned exam skills from faculty and MFC and FFC from nurses on the wards. Eleven percent of MS4 were never formally taught TE or DRE. MS3 and MS4 performed TE and/or DRE on <8% of newly admitted patients.nnnCONCLUSIONSnMS3 described improved comfort with the GU skills at all time points during follow-up. This was particularly important because both MS3 and MS4 reported using their skills infrequently during their clinical training years.