Methylated DNA markers in urine aid in the selective identification of patients with prostate cancer as well as clinically significant pathology

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Background: Controversy surrounding prostate-specific antigen (PSA) based screening for prostate cancer (PCa) highlights the need for non-invasive assays that better discriminate patients with and without clinically significant prostate cancer (csPCa). Such distinction avoids overtreatment in patients with absent or indolent disease while capturing pathology that would derive benefit from intervention. We analyzed the presence of specific methylated DNA markers (MDMs) within urine samples of patients with biopsy proven PCa and assessed the ability to discriminate these patients from healthy controls with no clinical suspicion for PCa. Methods: 24 healthy volunteers with no clinical suspicion for PCa were age-matched to 24 patients with biopsy-confirmed disease across all Gleason scores. Urine collected from subjects was centrifuged with the cell-free supernatant analyzed in a blinded fashion for methylation signal within specific DNA sequences across 14 genes ( HES5, ZNF655, ITPRIPL1, MAX.chr3.193, SLCO3A1, CHST11, SERPINB9, WNT3A, KCNB2, GAS6, AKR1B1, MAX.chr3.727, GRASP, ST6GALNAC2) by target enrichment long-probe quantitative-amplified signal assays. A patient was considered to have a positive MDM panel if any individual marker exceeded the corresponding100% specificity cut-off value (overall MDM panel specificity of 100%). MDM panel positivity was used to evaluate the sensitivity for distinguishing patients with PCa (any Gleason score) from controls as well as discriminate csPCa cancers from PCa Gleason 6. Results: Median age of healthy controls and PCa patients was 70 years (IQR 67-72) and 65 years (IQR 61-71), respectively. Median PSA was 6.4 (IQR 4.9-9.0) among PCa patients, including median PSA of 5 (IQR 4.0-6.1) for Gleason 6, and 7.8 (IQR 5.1-9.2) for Gleason ≥7 disease. Gleason 6, Gleason 7, and Gleason 8+ cancer was noted in 8, 10, and 6 patients, respectively. Utilizing an overall specificity cut-off of 100% for discriminating normal controls from PCa cases across the MDM panel revealed an overall sensitivity of 83% (95% CI: 63-95%) for detection of PCa (6 of 8 Gleason 6, 9 of 10 Gleason 7, 5 of 6 Gleason 8+) and 88% (95% CI: 62-98%) for csPCa (Gleason ≥ 7). When considering a 100% specificity threshold for controls and Gleason 6 patients, the sensitivity the MDM panel was 69% (95% CI: 41-89%) for csPCa (6 of 10 Gleason 7, 5 of 6 Gleason 8+). Conclusions: We describe a panel of 14 MDMs within urine that offer high specificity and sensitivity for detection of prostate cancers as well as selective identification of clinically significant disease states. Prospective comparison between urine MDMs and PSA blood testing is necessary to discern the differential clinical impact of each screening methodology.

Telemedicine in Urology: The Socioeconomic Impact

The emergence of the COVID-19 pandemic and subsequent public health emergency (PHE) have propelled telemedicine several years into the future. With the rapid adoption of this technology came socioeconomic inequities as minority communities disproportionately have yet to adopt telemedicine. Telemedicine offers solutions to patient access issues that have plagued urology, helping address physician shortages in rural areas and expanding the reach of urologists. The Centers for Medicare & Medicaid Services have adopted changes to expand coverage for telemedicine services. The expectation is that telemedicine will continue to be a mainstay in the health care system with gradual expansion in utilization.

A Serum C-Reactive Protein and Procalcitonin-Based Risk Score to Predict Urinary Infection in Patients with Obstructive Urolithiasis Undergoing Decompression

Objective: The aim of this study was to develop a risk score utilizing C-reactive protein (CRP) and procalcitonin to better predict a clinical infection for patients with obstructive urolithiasis. Methods: A retrospective review was performed of patients presenting to the emergency room from December 2017 to February 2019 and who underwent upper urinary tract decompression due to concern for infection in the setting of obstructing urolithiasis. Over 30 clinical parameters were assessed and a composite risk score was created. Univariate and multivariate, forward, stepwise regression analyses were performed to identify predictors of true urinary tract infection (UTI). Results: Ninety-eight patients met inclusion criteria, of which a true UTI was identified in 50 (51%). The standard model of serum white blood cells >15 or temperature >38°C had an area under curve (AUC) of only 0.67 to predict UTI. A multivariable regression-based 4-point risk score (1 point for each of the following: positive urinary Gram stain, perinephric fat stranding on CT, serum CRP >21.95, and serum procalcitonin >0.36) had an AUC of 0.91 to predict UTI. Individually, these components had an AUC of 0.68, 0.68, 0.80, and 0.77, respectively. The chances of confirmed UTI were 8%, 11%, 68%, and 100% for risk scores of 0, 1, 2, and 3 to 4, respectively (p < 0.001). Conclusions: Only 50% of patients with a suspected UTI and an obstructing stone were ultimately confirmed to have a UTI. A risk score consisting of Gram stain, perinephric fat stranding, CRP, and procalcitonin can improve UTI prediction and warrants further study.

Intraoperative application of platelet-rich plasma to the neurovascular bundles during radical prostatectomy: A prospective clinical trial

TPS380

Background: Radical prostatectomy (RP) is the most common surgical treatment for prostate cancer (PC). Yet even with nerve-sparing RP (NS-RP), a significant proportion of men experience transient or permanent erectile dysfunction (ED) partially due to intraoperative neurovascular bundle (NVB) damage from thermal or mechanical trauma. Studies have shown that platelet released growth factors counteract trauma and facilitate healing. We evaluate the use of platelet rich plasma (PRP) to facilitate early nerve healing and decrease ED after NS-RP. Methods: A prospective, open label, 20 subject human trial evaluating intraoperative topical NVB PRP application was approved by the IRB and FDA under an Investigational Device Exemption (IDE 16915) for the investigational use of an approved blood separation device. Men aged 50-60 with newly diagnosed, localized PC and normal preoperative sexual and urinary function, defined as a Sexual Health Inventory for Men (SHIM) score of >19 and an answer of “none” on question 5 of the Expanded Prostate Cancer Index Composite (EPIC) are eligible. Intraoperatively, a 10ml PRP product is created from a 180 mL sample of the patient’s whole blood using the Angel Concentrated Platelet Rich Plasma System (Cytomedix, Inc., Gaithersburg, MD USA). PRP is applied via mechanical transfer to the NVB after completion of the vesicourethral anastomosis. The primary endpoint is the safety and tolerability of PRP on the NVB after NS-RP. Secondary endpoints include feasibility of intraoperative PRP application and longitudinal assessment of erectile function and urinary continence by questionnaire administration at 3, 6, 9, 12 and 18 months after NS-RP. Clinical trial information: NCT02957149.

The Current State of Telemedicine in Urology

Telemedicine use in urology is an evolving practice. In this article, the authors review the early experience of telemedicine specifically as it relates to urologic practice and discuss the future implications and the utility of telemedicine as it applies to other fields.

Telemedicine in Urology: State of the Art

Whereas telemedicine is recognized as one of the fastest-growing components of the healthcare system, the status of telemedicine use in urology is largely unknown. In this narrative review, we detail studies that investigate the use of televisits and teleconsultations for urologic conditions. Moreover, we discuss current regulatory and reimbursement policies. Finally, we discuss the significant barriers to widespread dissemination and implementation of telemedicine and reasons why the field of urology may be positioned to become a leader in the provision of telemedicine services.

Mapping prostate cancer (CaP) recurrence after prostatectomy with c-11 choline PET/CT and 3T pelvic MRI in the contemporary era

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Background: The purpose of this study was to identify site-specific recurrence patterns for patients (pts) with biochemical recurrence (BCR) after prostatectomy (RP) using C-11 Choline PET/CT (C11Ch) and 3T pelvic MRI with endorectal coil (pMRI). Methods: Between 2008 and 2006, 2,466 men underwent C11Ch and pMRI for BCR after RP. From this cohort, we identified 261 pts who received no adjuvant or salvage therapy (androgen deprivation or radiation). Suspected radiographic relapse was confirmed by biopsy (46%) or progression/response to treatment in concordance with subsequent rise/decline in PSA (54%). Results: Of the 261 men evaluated, 202 (75%) had positive pMRI, C11Ch or both. Seventy nine (39%), 105 (52%) and 18 (9%) pts had high, intermediate, and low risk CaP, respectively at RP. Median PSA at the time of positive scan was 2.3 ng/mL, with a median time from BCR to radiographic disease identification of 15 months. Of these 202 men, 67 (33%) harbored prostate fossa recurrence only, 44 (22%) had a combination of local and metastatic disease and 91 (45%) had metastatic disease without local recurrence. Forty (20%) pts had pelvic nodal recurrence only and 18 (9%) had perirectal nodal involvement. Median PSA for pts with local only recurrence, distant metastases only, and local + distant disease was 2.3, 2.7 and 2.2 ng/mL, respectively, with a median interval from BCR to positive scan of 16.7, 7.9 and 11 months. Imaging revealed that 33% to 66% of our cohort would have all sites of disease treated by salvage RT depending on the extent of the treatment field Conclusions: C11Ch and pMRI were used to identify recurrence patterns in pts with BCR after RP only. At median PSA of 2.3 ng/ml, our study demonstrates a low rate of local-only recurrence, higher than anticipated frequency of metastatic recurrence with peak frequency within the pelvic lymph nodes, and substantial perirectal recurrences. Despite the high rates of distant recurrences, 2/3 of our cohort had their disease limited to the pelvis and could be potential candidates for local therapies, including salvage radiation.

Crowdsourcing Assessment of Surgeon Dissection of Renal Artery and Vein During Robotic Partial Nephrectomy: A Novel Approach for Quantitative Assessment of Surgical Performance

INTRODUCTION

We sought to describe a methodology of crowdsourcing for obtaining quantitative performance ratings of surgeons performing renal artery and vein dissection of robotic partial nephrectomy (RPN). We sought to compare assessment of technical performance obtained from the crowdsourcers with that of surgical content experts (CE). Our hypothesis is that the crowd can score performances of renal hilar dissection comparably to surgical CE using the Global Evaluative Assessment of Robotic Skills (GEARS).

METHODS

A group of resident and attending robotic surgeons submitted a total of 14 video clips of RPN during hilar dissection. These videos were rated by both crowd and CE for technical skills performance using GEARS. A minimum of 3 CE and 30 Amazon Mechanical Turk crowdworkers evaluated each video with the GEARS scale.

RESULTS

Within 13 days, we received ratings of all videos from all CE, and within 11.5 hours, we received 548 GEARS ratings from crowdworkers. Even though CE were exposed to a training module, internal consistency across videos of CE GEARS ratings remained low (ICC = 0.38). Despite this, we found that crowdworker GEARS ratings of videos were highly correlated with CE ratings at both the video level (R = 0.82, p < 0.001) and surgeon level (R = 0.84, p < 0.001). Similarly, crowdworker ratings of the renal artery dissection were highly correlated with expert assessments (R = 0.83, p < 0.001) for the unique surgery-specific assessment question.

CONCLUSIONS

We conclude that crowdsourced assessment of qualitative performance ratings may be an alternative and/or adjunct to surgical experts' ratings and would provide a rapid scalable solution to triage technical skills.

Predicting Life Expectancy in Men Diagnosed with Prostate Cancer

CONTEXT

The widespread use of prostate-specific antigen (PSA) screening has led to the detection of more indolent prostate cancer (PCa) in healthy men. PCa treatment and screening must therefore balance the potential for life gained against the potential for harm. Fundamental to this balance is physician awareness of a patient's estimated life expectancy (LE).

OBJECTIVE

To review the evidence on LE differences between men diagnosed with PCa and the general population. To examine clinician- and model-predicted LE and publicly available LE calculators.

EVIDENCE ACQUISITION

A comprehensive search of the PubMed database between 1990 and September 2014 was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Free text protocols of the following search terms were used "life expectancy prostate cancer", "life expectancy non-cancer", "non-cancer mortality prostate", and "comorbidity-adjusted life expectancy". Two internet search engines were queried daily for 1 mo for the search term "life expectancy calculator", and the top 20 results were examined.

EVIDENCE SYNTHESIS

Of 992 articles and 32 websites screened, 17 articles and nine websites were selected for inclusion. Men with non-screening-detected PCa and distant disease at diagnosis were found to have shorter LE than age-matched peers, whereas men with localized PCa had prolonged LE. In general, clinician-predicted 10-yr LE was pessimistic and of limited accuracy; however, model-predicted LE provided only modest improvements in accuracy (c-index of models 0.65-0.84). Online LE calculators provide consistent LE estimates, but government life tables provide LE estimates near the mean for all calculators examined.

CONCLUSIONS

The accuracy of clinician-predicted survival is limited, and while available statistical models offer improvement in discrimination, it is unclear whether they provide advantages over freely available government life tables.

PATIENT SUMMARY

We examined differences in life expectancy between men diagnosed with prostate cancer and the general population, and ways of predicting life expectancy to help guide treatment decisions. We found that current models for predicting life expectancy specific to prostate cancer might not be any better than government life tables or simple rules of thumb.

Evaluation of potential distractors in the urology operating room

BACKGROUND AND PURPOSE

Surgical outcomes depend on patient and disease-related factors, as well as the technical skill of the surgeon. Various distractions in the operating room (OR) environment have been shown to negatively impact a surgeon's performance. A survey was conducted with the objective to evaluate and characterize distractions during urologic surgery.

METHODS

An Internet-based survey was distributed to 2057 international urologists via email between April and October 2011; questions focused on a variety of disruptive factors postulated to have a negative impact on surgical performance.

RESULTS

Of the 523 (25%) respondents, 58% practiced in North America, 42% were from an academic institution, and 68% had completed a clinical fellowship. In an average year, 83% reported having operated at least once while sleep deprived, 84% when significantly ill, 55% with a musculoskeletal injury, and 65% under significant social stress. Up to 38% reported that on at least one occasion, such "internal distractions" had significantly affected surgical performance and 14% perceived that at least one surgical complication was caused mainly by an internal distraction. Less than 50% had ever cancelled surgery because of an internal distraction. Music was routinely played in the OR by 57% of respondents, >67% reported answering pages and discussing consults while operating, and 25% reported "commonly" working with scrub nurses/techs that were unfamiliar with the procedure and/or instruments. Only 44% had consistent individual(s) assisting, and 27% reported that the scrub nurse/tech would "commonly" scrub out during a critical portion of the procedure. Overall, 14.5% reported that at least one complication had occurred mainly because of such "external" or "interactive" distractions.

CONCLUSIONS

Urologists face various distractions in the OR that can negatively impact surgical performance, potentially compromising patient outcomes and safety. Further studies are needed to elucidate the true impact of such distractions and to develop strategies to mitigate their effects.

Robot-assisted and laparoscopic repair of ureteropelvic junction obstruction: a systematic review and meta-analysis

CONTEXT

Over the last two decades, minimally invasive treatment options for ureteropelvic junction obstruction (UPJO) have been developed and popularized.

OBJECTIVE

To critically analyze the current status of laparoscopic and robotic repair of UPJO.

EVIDENCE ACQUISITION

A systematic literature review was performed in November 2012 using PubMed. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta-analyses criteria.

EVIDENCE SYNTHESIS

Multiple series of laparoscopic pyeloplasty have demonstrated high success rates and low perioperative morbidity in pediatric and adult populations, with both the transperitoneal and retroperitoneal approaches. Data on pediatric robot-assisted pyeloplasty are increasingly becoming available. A larger number of cases have also been reported for adult patients, confirming that robotic pyeloplasty represents a viable option for either primary or secondary repair. Robot-assisted redo pyeloplasty has been mostly described in the pediatric population. Different technical variations have been implemented with the aim of tailoring the procedure to each specific case. The type of stenting, retrograde versus antegrade, continues to be debated. Internal-external stenting as well as a stentless approach have been used, especially in the pediatric population. Comparative studies demonstrate similar success and complication rates between minimally invasive and open pyeloplasty in both the adult and pediatric setting. A clear advantage in terms of hospital stay for minimally invasive over open pyeloplasty was observed only in the adult population.

CONCLUSIONS

Laparoscopy represents an efficient and effective less invasive alternative to open pyeloplasty. Robotic pyeloplasty is likely to emerge as the new minimally invasive standard of care whenever robotic technology is available because its precise suturing and shorter learning curve represent unique attractive features. For both laparoscopy and robotics, the technique can be tailored to the specific case according to intraoperative findings and personal surgical experience.

Natural orifice transluminal endoscopic surgery (NOTES): where are we going? A bibliometric assessment

The aim of this study was to analyse natural orifice transluminal endoscopic surgery (NOTES)-related publications over the last 5 years. A systematic literature search was done to retrieve publications related to NOTES from 2006 to 2011. The following variables were recorded: year of publication; article type; study design; setting; Journal Citation Reports® journal category; authors area of surgical speciality; geographic area of origin; surgical procedure; NOTES technique; NOTES access route; number of clinical cases. A time-trend analysis was performed by comparing early (2006-2008) and late (2009-2011) study periods. Overall, 644 publications were included in the analysis and most papers were found in general surgery journals (50.9%). Studies were most frequently clinical series (43.9%) and animal experimental (48%), with the articles focusing primarily on cholecystectomy, access creation and closure, and peritoneoscopy. Pure NOTES techniques were performed in most of the published reports (85%) with the remaining cases being hybrid NOTES (7.4%) and NOTES-assisted procedures (6.1%). The access routes included transgastric (52.5%), transcolonic (12.3%), transvesical (12.5%), transvaginal (10.5%), and combined (12.3%). From the early to the late period, there was a significant increase in the number of randomised controlled trials (5.6% vs 7.2%) or non-randomised but comparative studies (5.6% vs 22.9%) (P < 0.001) and there was also a significant increase in the number of colorectal procedures and nephrectomies (P = 0.002). Pure NOTES remained the most studied approach over the years but with increased investigation in the field of NOTES-assisted techniques (P = 0.001). There was also a significant increase in the adoption of transvesical access (7% vs 15.6%) (P = 0.007). NOTES is in a developmental stage and much work is still needed to refine techniques, verify safety and document efficacy. Since the first description of the concept of NOTES, >2000 clinical cases, irrespective of specialty, have been reported. NOTES remains a field of intense clinical and experimental research in various surgical specialities.

Robot-assisted sacrocolpopexy: description and video

Pelvic organ prolapse is a common problem faced by many women, resulting in significant morbidity and negatively impacting quality of life. Sacrocolpopexy can treat women with vaginal vault prolapse, multicompartment prolapse, and/or a history of failed prolapse procedures. The transabdominal sacrocolpopexy has been shown, on multiple studies, to have one of the highest long-term success rates for repair of severe vault prolapse. The goals of surgical repair of vaginal vault prolapse include restoration of proper anatomy, maintenance of sexual function, and durability. Recently, there has been a push toward decreasing morbidity and recovery time associated with operative repair. Therefore, the robot-assisted sacrocolpopexy was developed and has gained widespread acceptance, given the excellent reproducible results, minimal complications, and high patient satisfaction. Our technique for robot-assisted sacrocolpopexy is presented.

Laparoendoscopic single-site and natural orifice transluminal endoscopic surgery in urology: a critical analysis of the literature

CONTEXT

Natural orifice transluminal endoscopic surgery (NOTES) and laparoendoscopic single-site surgery (LESS) have been developed to benefit patients by enabling surgeons to perform scarless surgery.

OBJECTIVE

To summarize and critically analyze the available evidence on the current status and future perspectives of LESS and NOTES in urology.

EVIDENCE ACQUISITION

A comprehensive electronic literature search was conducted in June 2010 using the Medline database to identify all publications relating to NOTES and LESS in urology.

EVIDENCE SYNTHESIS

In urology, NOTES has been completed experimentally via transgastric, transvaginal, transcolonic, and transvesical routes. Initial clinical experience has shown that NOTES urologic surgery using currently available instruments is indeed possible. Nevertheless, because of the immaturity of the instrumentation, early cases have demanded high technical virtuosity. LESS can safely and effectively be performed in a variety of urologic settings. As clinical experience increases, expanding indications are expected to be documented and the efficacy of the procedure to improve. So far, the quality of evidence of all available studies remains low, mostly being small case series or case-control studies from selected centers. Thus, the only objective benefit of LESS remains the improved cosmetic outcome. Prospective, randomized studies are largely awaited to determine which LESS procedures will be established and which are unlikely to stand the test of time. Technology advances hold promise to minimize the challenging technical nature of scarless surgery. In this respect, robotics is likely to drive a major paradigm shift in the development of LESS and NOTES.

CONCLUSIONS

NOTES is still an investigational approach in urology. LESS has proven to be immediately applicable in the clinical field, being safe and feasible in the hands of experienced laparoscopic surgeons. Development of instrumentation and application of robotic technology are expected to define the actual role of these techniques in minimally invasive urologic surgery.

Nomenclature of natural orifice translumenal endoscopic surgery (NOTES) and laparoendoscopic single-site surgery (LESS) procedures in urology

INTRODUCTION

The twenty first century has witnessed some amazing advancements in surgery. In urology minimally invasive surgery has become the standard treatment for many disease processes and procedures. One of the newest innovations into this field has been the development of Natural Orifice Translumenal Endoscopic Surgery (NOTES) and Laparoendoscopic Single-site Surgery (LESS). While the practice and application of these new techniques are in their infancy, there has been a great deal of confusion regarding the nomenclature and terminology associated with these procedures. The aim of this publication is to attempt to define the many issues associated with the standardization of terminology for these procedures in order to promote effective scientific progress and communication.

MATERIALS AND METHODS

A literature search using Medline and pubmed focusing on all terminology to describe NOTES and LESS from 1990 to 2008 was done. In addition, various acronyms were searched using four separate online acronym databases. The information was recorded by number of citations and by the number of citations specific to the urologic literature. Based on common usage, definitions and criteria were developed to describe these procedures for current scientific publication. These terms were then collectively reviewed and agreed upon by the Urologic NOTES Working Group as a platform for consensus to begin the arduous process of standardization.

RESULTS

There is wide variation in the terminology and use of acronyms for natural orifice translumenal endoscopic surgery and laparo-endoscopic single-site surgery. The keyword literature search uncovered 8710 citations from MEDLINE and pubmed, with 363 citations specific to urology. There was significant overlap in the search of different terms. The search of established abbreviation and acronym databases revealed many citations, but relatively few specific to urology.

CONCLUSION

Standardization of the nomenclature applied to natural orifice transluminal endoscopic surgery (NOTES) and laparo-endoscopic single-site surgery (LESS) is essential as the body of literature continues to grow in order to allow clear and precise scientific communication. As the techniques continue to evolve, we propose that NOTES and LESS be designated as the common terms to define these new procedures in urology.

Robotic-assisted laparoscopy for the excision of a pelvic leiomyosarcoma

The indications for robot-assisted laparoscopic surgery in Urology are expanding as surgical experience with robotic surgery mounts. We describe our experience of performing a laparoscopic robot-assisted excision of a pelvic leiomyosarcoma in an adult.

Current status of robotics in female urology and gynecology

Currently, there has been limited reporting and research in the female urology and gynecological literature concerning the use of robotics. To date, robotics have been utilized only for the treatment of three benign gynecologic conditions: benign hysterectomy; repair of vesicovaginal fistula; and sacrocolpopexy which is a treatment for posthysterectomy vaginal vault prolapse. We describe a novel minimally invasive technique of vaginal vault prolapse repair and present our initial experience. The surgical technique involves placement of five laparoscopic ports: three for the daVinci robot and two for the assistant. A polypropylene mesh is then attached to the sacral promontory and to the vaginal apex using Gortex sutures. Thirty-one patients underwent a robotic-assisted laparoscopic sacrocolpopexy at our institution in the past 24 months for severe symptomatic vaginal vault prolapse. Complications were limited to mild port site infections in two patients, which resolved with oral antibiotic therapy. While our early experience utilizing robotic repairs in female urology and gynecology is encouraging, long-term data are needed to confirm these findings and establish longevity of the repair.

Laparoscopic promontory sacral colpopexy: is the posterior, recto-vaginal, mesh mandatory?

OBJECTIVE(S)

The aim of our retrospective study was to determine if systematic placement of a posterior mesh, in addition to an anterior vesico-vaginal mesh, is necessary for laparoscopic treatment of pelvic organ prolapse.

METHODS

A laparoscopic promontory sacral colpopexy was performed in 108 patients, including 55 patients with a concurrent laparoscopic Burch procedure (50.9%). We compared 33 patients treated with a single anterior mesh (SAM) and 71 treated with a double, anterior and posterior, mesh (DM).

RESULTS

The difference between the SAM and DM groups was statistically significant in terms of posterior compartment failure (rectocele and/or enterocele): 31.3% and 5.9%, respectively (p=0.0006). This significant difference persisted in the Burch (B) group (p=0.001), but not in the non-Burch (NB) group (p=0.98). Among the SAM group, this difference between the B and NB groups, was significant (57.1% versus 0%; p=0.0015) and above all not a single posterior failure was observed in the NB group.

CONCLUSION(S)

The placement of a posterior mesh, if highly effective, appeared unnecessary in the absence of an associated Burch procedure or a patent posterior prolapse. The posterior mesh also increased risk of postoperative complications and side effects.

Justification of extraperitoneal laparoscopic access for surgery of the upper urinary tract

Laparoscopic surgery was originally developed by gynecologists and general surgeons. Based on their experience, the first successful laparoscopic procedures in urology were performed transperitoneally. However, this novel technique transformed traditionally retroperitoneal procedures into transperitoneal procedures, giving free rein to distinct intraperitoneal complications. Retroperitoneal laparoscopy was a later development in urology. This approach has gained increasing popularity throughout the years and has challenged the transperitoneal laparoscopic route in many aspects. This review focuses on the advantages of retroperitoneal laparoscopic surgery of the upper urinary tract.

Laparoscopic and robotic surgical training in urology

The most important change in urology during the past decade was the development of minimally invasive surgery, particularly laparoscopy. However, the main drawback of laparoscopy is a steep learning curve, which results from the significant changes in the surgical environment. Although laparoscopy can provide important advantages for the patient, including decreased length of hospitalization, decreased analgesic requirement, and a shortened postoperative convalescence, one concern has been whether laparoscopic techniques should be learned solely in the operating room. For example, sports, music, and aviation are practiced before an actual performance is ever undertaken. In this review, the advantages and limitations of all available training modalities in minimally invasive surgery are described. Testing basic laparoscopic skills on inanimate models, becoming familiar with the principles of dissection and hemostasis on living animals, and studying surgical anatomy on cadavers should be considered as indispensable and complementary elements for laparoscopic training in the future. In addition, telementoring with the help of modern image processing and virtual reality eventually may become the basis of tomorrow's surgical instruction.

Ureteral replacement using porcine small intestine submucosa in a porcine model

OBJECTIVES

To investigate an alternative technique using an onlay patch of porcine small intestine submucosa (SIS) allograft to bridge a ureteral defect. For ureteral strictures that fail endourologic management, few options are available for minimally invasive repair or reconstruction. Although laparoscopic interposition of a tubularized allograft of porcine SIS has great promise, animal studies have yielded mixed results.

METHODS

In 9 anesthetized female pigs, cystoscopy and retrograde pyelography were performed, and a ureteral stent was placed. Transperitoneal laparoscopic access was obtained, and a segment of ureter 2 cm long and encompassing one half the ureteral circumference was excised. An oval-shaped patch of SIS was sutured to the native ureter to cover the defect. In one control survival animal, the ureter was excised and a stent placed, but no SIS onlay was performed. Two pigs were killed immediately. In the survival group (6 pigs), the stents were removed at 1 week (n = 2), 2 weeks (n = 2), or 4 weeks (n = 2) and the corresponding animals were killed at 3 weeks (n = 2), 6 weeks (n = 2), and 9 weeks (n = 2). Intravenous urography was performed to evaluate renal function, and retrograde pyelography was performed after harvest to identify ureteral stricture or obstruction. The ureteral grafts were measured and examined histologically.

RESULTS

All 6 kidneys from the survival group were grossly normal, appeared promptly on intravenous urography, and were patent on retrograde pyelography. The control animal demonstrated complete ureteral obstruction. By 9 weeks, the SIS graft was replaced with ureteral tissue, including the muscle layers. The epithelium was primarily transitional epithelium, with focal intestinal metaplasia. The submucosa and ureteral musculature appeared histologically normal.

CONCLUSIONS

In the porcine model, a patch graft technique using SIS appears to induce ureteral regrowth. Renal function remained intact, and no evidence of stricture was demonstrated on radiographic imaging. Before clinical application of this technique, evaluation in a stricture model is required.

Potassium outward currents in freshly dissociated rabbit corpus cavernosum myocytes

PURPOSE

Cavernous smooth muscle cells have a key role in the control of penile erection and detumescence. In this study the types of smooth muscle cells and currents present in isolated rabbit corpus cavernosum myocytes were characterized.

MATERIALS AND METHODS

Immunohistochemical methods were used to identify cavernous smooth muscle cells. Currents were recorded from freshly dissociated myocytes using the whole cell and amphotericin perforated patch clamp techniques.

RESULTS

Cavernous myocytes were identified by alpha-smooth muscle actin and smooth muscle myosin immunoreactivity. Based on electrical properties at least 2 types of myocytes were present. Type I cells showed more depolarized membrane potentials, lower capacitance, higher input resistance and increased current densities at positive potentials than type II cells. In types I and II cells at voltages positive to 30 mV, maxi K+ channel (Ca2+ activated large conductance K+ channel or BK) blockade with iberiotoxin or charybdotoxin reduced outward currents by approximately 40% to 80% at 80 mV. Maxi K+ channel blocking did not affect cell membrane potential. Type II cells showed delayed rectifier K+ channel-type outward currents that were not detected in type I cells. Delayed rectifier K+ channel-type currents were resistant to iberiotoxin or charybdotoxin, activated at approximately -50 to -40 mV. and inactivated weakly.

CONCLUSIONS

The data suggest that cavernous smooth muscle cells are heterogeneous with at least 2 subtypes identified based on membrane potential, capacitance, input resistance, current density and delayed rectifier K+ channel expression. The activation threshold suggests that delayed rectifier K+ channels are open at the resting membrane potential and, therefore, contribute to control and regulation of the cavernous myocyte excitability.