Igor Sorokin

Epidemiology of stone disease across the world

Nephrolithiasis is a highly prevalent disease worldwide with rates ranging from 7 to 13% in North America, 5–9% in Europe, and 1–5% in Asia. Due to high rates of new and recurrent stones, management of stones is expensive and the disease has a high level of acute and chronic morbidity. The goal of this study is to review the epidemiology of stone disease in order to improve patient care. A review of the literature was conducted through a search on Pubmed®, Medline®, and Google Scholar®. This review was presented and peer-reviewed at the 3rd International Consultation on Stone Disease during the 2014 Société Internationale d’Urologie Congress in Glasgow. It represents an update of the 2008 consensus document based on expert opinion of the most relevant studies. There has been a rising incidence in stone disease throughout the world with a narrowing of the gender gap. Increased stone prevalence has been attributed to population growth and increases in obesity and diabetes. General dietary recommendations of increased fluid, decreased salt, and moderate intake of protein have not changed. However, specific recommended values have either changed or are more frequently reported. Geography and environment influenced the likelihood of stone disease and more information is needed regarding stone disease in a large portion of the world including Asia and Africa. Randomized controlled studies are lacking but are necessary to improve recommendations regarding diet and fluid intake. Understanding the impact of associated conditions that are rapidly increasing will improve the prevention of stone disease.

Irreversible electroporation of small renal masses: suboptimal oncologic efficacy in an early series

PurposeTo report on the first short-term oncologic outcomes of percutaneous irreversible electroporation for small renal masses.MethodsPatients with cT1a renal masses treated with irreversible electroporation from April 2013 through December 2016 were reviewed. Small, low complexity tumors were generally selected for irreversible electroporation using the NanoKnife® System (Angiodynamics, Latham, NY, USA). Surveillance imaging was performed post-operatively, and survival analysis was completed using the Kaplan–Meier method.ResultsA total of 42 tumors in 41 patients underwent irreversible electroporation. Mean tumor size was 2.0xa0cm with a median R.E.N.A.L nephrometry score of 5. Twenty-nine patients (71%) were discharged the same day of the procedure and no major (Clavien grade II or higher) intraoperative or post-operative complications occurred. Initial treatment success rate was 93%; our three failures (7%) underwent salvage radiofrequency ablation. With a mean follow-up of 22xa0months, 2-year local recurrence-free survival was 83% for patients with biopsy confirmed renal cell carcinoma, 87% with biopsy confirmed or a history of renal cell carcinoma, and 92% for the intent-to-treat cohort.ConclusionsAlthough with low morbidity, in comparison to extirpation and conventional thermal ablation technologies, irreversible electroporation has suboptimal short-term local disease control results in this series of small, low complexity tumors. Larger series and longer follow-up will determine the durability of this modality.

Robot-Assisted Versus Open Simple Prostatectomy for Benign Prostatic Hyperplasia in Large Glands: A Propensity Score–Matched Comparison of Perioperative and Short-Term Outcomes

OBJECTIVEnTo report the largest comparative analysis of robotic vs open simple prostatectomy (OSP) for large-volume prostate glands.nnnMATERIALS AND METHODSnWe retrospectively reviewed 103 patients that underwent open and 64 patients that underwent robotic simple prostatectomy from 2012 to 2016 at a single institution. A propensity score-matched analysis was performed with five covariates, including age, body mass index, race, Charlson comorbidity index, and prostate volume. Perioperative, postoperative, and functional outcomes were compared between groups.nnnRESULTSnAfter propensity score matching there were 59 patients in each group available for comparison. There was no statistically significant difference between groups for all preoperative demographic variables. Robotic compared with OSP demonstrated a significant shorter average length of stay (LOS) (1.5 vs 2.6 days, pu2009<u20090.001), but longer mean operative time (161 vs 93 minutes, pu2009<u20090.001). The robotic approach was also associated with a lower estimated blood loss (339 vs 587u2009mL, pu2009<u20090.001) and lower percentage hematocrit drop (12.3% vs 19.5%, pu2009=u20090.001). Two patients required blood transfusions in the robot group compared with four in the open group, but this was not significant (pu2009=u20090.271). Improvements in maximal flow rate, International Prostate Symptom Score, quality of life, postvoid residual, and postoperative prostate-specific antigen levels were similar before and after surgery for both groups, but there was no difference between groups. There was no difference in complications between groups.nnnCONCLUSIONnRobotic simple prostatectomy is a safe and effective treatment for the surgical management of benign prostatic hyperplasia. It provides similar function outcomes to the open approach; however, offers the advantage of reduced LOS and reduced blood loss.

The Decline of Laparoendoscopic Single-Site Surgery: A Survey of the Endourological Society to Identify Shortcomings and Guidance for Future Directions

INTRODUCTIONnTo analyze the most recent temporal trends in the adoption of urologic laparoendoscopic single-site (LESS), to identify the perceived limitations associated with its decline, and to determine factors that might revive the role of LESS in the field of minimally invasive urologic surgery.nnnMATERIALS AND METHODSnA 15 question survey was created and sent to members of the Endourological Society in September 2016. Only members who performed LESS procedures in practice were asked to respond.nnnRESULTSnIn total, 106 urologists responded to the survey. Most of the respondents were from the United States (35%) and worked in an academic hospital (84.9%). Standard LESS was the most popular approach (78.1%), while 14.3% used robotics, and 7.6% used both. 2009 marked the most popular year to perform the initial (27.6%) and the majority (20%) of LESS procedures. The most common LESS procedure was a radical/simple nephrectomy (51%) followed by pyeloplasty (17.3%). In the past 12 months, 60% of respondents had performed no LESS procedures. Compared to conventional laparoscopy, respondents only believed cosmesis to be better, however, this enthusiasm waned over time. Worsening shifts in enthusiasm for LESS also occurred with patient desire, marketability, cost, safety, and robotic adaptability. The highest rated factor to help LESS regain popularity was a new robotic platform.nnnCONCLUSIONnThe decline of LESS is apparent, with few urologists continuing to perform procedures attributed to multiple factors. The availability of a purpose-built robotic platform and better instrumentation might translate into a renewed future interest of LESS.

Successful Outcomes in Robot-Assisted Laparoscopic Pyeloplasty Using a Unidirectional Barbed Suture

INTRODUCTIONnIntracorporeal suturing is considered to be the most challenging aspect of laparoscopic and robotic surgery. To overcome this problem, barbed self-retaining sutures have been effectively employed in various minimally invasive endourologic surgeries. However, the use of this suture has been recently cautioned for pyeloplasty due to a high failure rate. Our objective was to report our experience using barbed suture during robotic pyeloplasty.nnnMETHODSnWe retrospectively identified 13 consecutive patients who underwent robotic pyeloplasty with a barbed monofilament (4-0u2009V-Loc™) suture for the ureteropelvic anastomosis from 2011 to 2014. We compared these patients to 12 consecutive patients who underwent robotic pyeloplasty with a 4-0 nonbarbed suture from 2007 to 2011. We evaluated patient demographics, operative times, preoperative and postoperative symptoms, renal function, and diuretic renograms (DRG). Successful repair was defined as resolution of preoperative symptoms and/or T½ improvement on DRG to less than 20 minutes.nnnRESULTSnThe median age was 26 (interquartile range [IQR] 20.7-38) years and 35 (IQR 18.3-44) years for the barbed and nonbarbed suture groups, respectively. In the barbed suture group, preoperative DRG revealed ureteropelvic junction obstruction (UPJO) in 11 patients, equivocal UPJO (T½ 10-20 minutes) in one patient, and no obstruction in one patient. In the nonbarbed group, preoperative DRG revealed UPJO in 10 patients, equivocal UPJO in one patient, and no obstruction in one patient. In the barbed suture group, postoperative DRG was obtained in 11 patients, which showed no obstruction in 10/11 patients with 92% of patients experiencing symptom resolution. Similarly, postoperative DRG was obtained in 11 patients in the nonbarbed group, which showed no obstruction in 10/11 patients with 100% postoperative symptom resolution.nnnCONCLUSIONSnIn the largest series reporting use of V-Loc suture for robotic pyeloplasty, the V-Loc suture was safely and effectively used for robotic pyeloplasty repair.

Re: Time to consider integration of a formal robotic-assisted surgical training program

In the second Journal of Robotic Surgery (JORS) TwitterTM journal club, we discussed Vetter and colleague’s manuscript regarding survey results of robotic surgical training for obstetric and gynecology residents in the United States [1]. In this study, 177 residents completed a 31-item questionnaire that covered a range of topics surrounding robotic training. Surprisingly, over 30% of respondents did not need to complete a robotics training course prior to working on the console, and 50% did not have formal evaluations during their robotic training, When asked what area of robotic training was most and least useful, 50% thought that the dual console was the most useful and 50% thought that online modules were least useful. Personal time was often stated as a major limitation to robotic training, given most residents are not allotted robotic training time during a normal workweek. Discussion ensued (see supplementary Table 1). There was consensus that formal robotic surgery curriculum is absolutely necessary. Because there is significant variation between centers (1) any training curriculum should not focus on a specific simulator, robot, or model (2), as mentioned in a review of robotic training curriculum [2]. Virtual simulators, as well as dry and wet lab environments (3), are necessary to teach residents to use the pedals, clutch, and drive the camera (4), but allowing residents to use such modalities requires specific curriculum and direction (5). In addition, trainees need formal evaluations of their simulation progress (6). Because access to simulation centers often does not align with hours residents are free (7), formal evaluations from faculty can be difficult to obtain. Video recording of simulator work is one potential solution (8), but this might not capture true hand technique at the console (9). Live mentoring with both trainee and faculty in a simulation center would allow more opportunities to correct trainees, as well as allow trainees a closer opportunity to watch how faculty operate on a simulator up close (10). These sentiments were echoed in the first poll of the discussion (Fig. 1), where the majority of respondents felt live faculty presence was the best way to evaluate trainees completing a robotic training curriculum. However, downsides to simulation were also mentioned. For example, digital simulators are lacking with tissue handling and dissection (11) and there is limited access to animal and cadaver simulation (12). Dry labs might be a more ideal setting for practice, as suturing is more realistic, plus there are models that allow dissection practice (13). Another area of debate was resident exposure to bedside assisting during robotic surgery. In the second poll of the journal club, the majority of respondents (73%) felt that trainees need to do at least 10 cases as a bedside assistant (Fig. 2). Bedside assisting gives a thorough exposure to robotic arm mechanics and function, and is sometimes a trainee’s first exposure to laparoscopy (14–15). Some residents might view the bedside assist as a menial task, however, it is an invaluable experience that ultimately makes a better robotic surgeon (16). And, while the quantity of cases at the bedside might not be the most important metric (17), achieving competence at the bedside is a must (18). Ultimately, a multi-modality curriculum, with live simulation and timely feedback by faculty, are important to ensure trainees receive appropriate robotics exposure prior Electronic supplementary material The online version of this article (https ://doi.org/10.1007/s1170 1-018-0794-5) contains supplementary material, which is available to authorized users.

National Utilization of Partial Nephrectomy Pre- and Post- AUA Guidelines: Is This as Good as It Gets?

Micro‐Abstract Local excision of small kidney cancers appears to treat cancer equally with added benefits of preserving more kidney tissue. After publication of guidelines recommending local excision where feasible, proportions of this procedure continue to increase and it is more widely spread. The rate of adoption of this complex procedure has slowed likely due to decreasing incidence of kidney cancer and emergence of other options. Background: The purpose of the study was to compare utilization and predictors of partial nephrectomy (PN) in the pre‐ and post‐guideline eras. Materials and Methods: American Board of Urology certification/recertification operative logs were reviewed from 2003 to 2014. Nephrectomy cases were extracted using Current Procedural Terminology codes. The cases were then stratified according to pre‐guidelines (2003‐October 2009) and post‐guidelines (November 2009‐2014). Multivariable logistic regression was used to evaluate patient, surgeon, and practice characteristics as predictors of PN. A general linear model with regression analysis was used to evaluate the change in PN over time relative to the incidence of renal cell carcinoma (RCC). Results: We identified 20,402 and 20,729 nephrectomies in the pre‐ and post‐guidelines eras, respectively. In multivariable analysis, the post‐guidelines group was more likely to undergo PN (odds ratio, 1.87; P < .001). The pre‐ as well as post‐guidelines groups had a higher likelihood of undergoing PN with an open approach, higher‐volume surgeons, and younger patient age (P < .05). Surgeon subspecialty and US region were no longer significant factors after guidelines publication. Number of PN normalized to the incidence of RCC continued to increase over time (0.14%/y; R2 = 0.77; P < .001). Conclusion: Partial nephrectomy in the post‐guidelines era is no longer confined to urological subspecialists or certain densely populated US regions. Although rates of PN continue to increase relative to the recently decreasing overall incidence of RCC, the slope has leveled off somewhat. This is likely related to clinical intricacies of the best treatment modality and technologic advances rather than changes related to guidelines publication.

Phenazopyridine: A Preoperative Way to Identify Ureteral Orifices

OBJECTIVEnTo identify difficult to see ureteral orifices (UOs), urologists need a method to stain the urine. Phenazopyridine, a urinary analgesic which discolors the urine orange, can be administered orally preoperatively. We evaluated the usefulness of phenazopyridine in identifying the UOs and optimal timing of administration.nnnMETHODSnAdult patients undergoing endoscopic procedures at the Stratton VA were prospectively enrolled. Preoperative metabolic panels were reviewed. Exclusion criteria were renal insufficiency (creatinine clearanceu2009<50u2009mL/min), severe hepatitis or severe liver disease, glucose-6-phosphate dehydrogenase deficiency, previous hypersensitivity to phenazopyridine, or pregnancy. In phase 1, patients undergoing office flexible cystoscopy were administered 200u2009mg phenazopyridine the morning of the procedure. Because of the robust orange color of the urine, phase 2 was implemented. In phase 2, patients undergoing rigid cystoscopy in the operating room took 200u2009mg phenazopyridine at 7 PM the night before surgery. Upon entry into the bladder, UOs were identified and urine color was graded (0u2009=u2009no dye, 1u2009=u2009weak, 2u2009=u2009moderate, and 3u2009=u2009strong). Patients were assessed postoperatively for side effects.nnnRESULTSnFive patients were included in phase 1. The mean time from medication to cystoscopy was 153u2009minutes (range 17-304u2009minutes). One-third of patients had excretion of grade 3 orange urine that obscured inspection of the bladder mucosa. The study design was adjusted and we transitioned to phase 2. Twenty-three patients were enrolled in phase 2. The mean time from phenazopyridine dose to cystoscopy was 14u2009hours (range 13-17u2009hours). Seventy-three percent of patients had grade 2 efflux from the UOs.nnnCONCLUSIONnPhenazopyridine can successfully identify UOs and can be administered as early as the evening before the procedure.

Ten-year outcomes of renal tumor radiofrequency ablation

PURPOSEnWe reviewed long-term oncologic outcomes in patients with renal tumors treated with radio frequency ablation more than 10 years ago.nnnMATERIALS AND METHODSnWe retrospectively reviewed the records of patients with renal tumors who underwent radio frequency ablation from November 2000 to August 2007. Demographic, clinical and radiological data were assessed to determine evidence of disease recurrence. Patients with familial renal cell carcinoma syndromes were excluded from study. We calculated disease-free, metastasis-free, cancer specific and overall survival with the Kaplan-Meier method. Subgroup analysis of patients who had at least 10 years followup was performed to determine actual 10-year survival. Analysis was also performed based on tumor size.nnnRESULTSnA total of 112 tumors in 106 patients were treated with radio frequency ablation. Median followup was 79 months (IQR 28.9-121.1) and mean ± SD tumor size was 2.5 ± 0.8 cm. Initial technical success was achieved in 97% of cases. There were 10 recurrences. Kaplan-Meier 6-year disease-free and cancer specific survival rates were 89% and 96%, respectively. Disease-free survival decreased to 68% for tumors greater than 3 cm. In the subgroup with at least 10-year followup the actual disease-free, cancer specific and overall survival rates were 82%, 94% and 49%, respectively. No patient experienced recurrence after 5 years.nnnCONCLUSIONSnRadio frequency ablation is a safe and effective treatment option for small renal masses less than 3 cm in diameter. We report good oncologic outcomes with actual 10-year survival data. No recurrence developed after 5 years. Tumors greater than 3 cm have significantly poorer outcomes.Purpose: We reviewed long-term oncologic outcomes in patients with renal tumors treated with radio frequency ablation more than 10 years ago. Materials and Methods: We retrospectively reviewed the records of patients with renal tumors who underwent radio frequency ablation from November 2000 to August 2007. Demographic, clinical and radiological data were assessed to determine evidence of disease recurrence. Patients with familial renal cell carcinoma syndromes were excluded from study. We calculated disease-free, metastasis-free, cancer specific and overall survival with the Kaplan-Meier method. Subgroup analysis of patients who had at least 10 years followup was performed to determine actual 10-year survival. Analysis was also performed based on tumor size. Results: A total of 112 tumors in 106 patients were treated with radio frequency ablation. Median followup was 79 months (IQR 28.9–121.1) and mean ± SD tumor size was 2.5 ± 0.8 cm. Initial technical success was achieved in 97% of cases. There were 10 recurrences. Kaplan-Meier 6-year disease-free and cancer specific survival rates were 89% and 96%, respectively. Disease-free survival decreased to 68% for tumors greater than 3 cm. In the subgroup with at least 10-year followup the actual disease-free, cancer specific and overall survival rates were 82%, 94% and 49%, respectively. No patient experienced recurrence after 5 years. Conclusions: Radio frequency ablation is a safe and effective treatment option for small renal masses less than 3 cm in diameter. We report good oncologic outcomes with actual 10-year survival data. No recurrence developed after 5 years. Tumors greater than 3 cm have significantly poorer outcomes.

Periarterial papaverine to treat renal artery vasospasm during robot-assisted laparoscopic partial nephrectomy

Renal artery vasospasm can be a troublesome complication during robot-assisted laparoscopic partial nephrectomy. Urologists performing this procedure, especially if utilizing selective arterial vascular microdissection, should be aware of using papaverine for both prevention and treatment of renal artery vasospasm. We present a 33-year-old male who developed severe renal artery vasospasm just with hilar dissection causing the kidney to become ischemic. Papaverine was topically applied on the renal arteries resulting in vasodilation and reperfusion of the kidney. Our objective of this report is to raise awareness of this complication as well as to review the literature on periarterial papaverine use and the dosing for topical applications.