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Papers by Stanislav Kocherov

Journal of Pediatric Urology, 2018

Background: Although shown to be safe in infancy, robotic-assisted laparoscopic pyeloplasty (RALP... more Background: Although shown to be safe in infancy, robotic-assisted laparoscopic pyeloplasty (RALP) for ureteropelvic junction obstruction (UPJO) is most commonly performed in older children and adolescents. Objective: This study examined a contemporary RALP experience at a single tertiary pediatric center and compared outcomes in infants aged ≤1 year with an older cohort. Methods and Design: All RALP procedures were entered into an Institutional Review Board-approved data registry from 2012-2016. Patients were retrospectively grouped according to age. The primary outcome was success rate. Secondary outcomes included complications and length of hospital stay. Failure was defined as the need for secondary surgical intervention for UPJO or worsening urinary tract dilation on imaging. Statistical analysis was performed using SPSS version 20. Mann-Whitney U testing was used for comparison. Results: A total of 138 patients underwent RALP during 2012-2016, with a median age of 6 years (IQR 1,13.25) and a male:female ratio of approximately 2:1. Of these, 34 (24.6%) were aged ≤1 year. Of all patients, 60 (43.5%) presented with a history of prenatal hydronephrosis, and 32% had a crossing vessel causing obstruction. An indwelling stent was placed in antegrade fashion in 71% of cases, and 18% had a percutaneously placed externalized stent. There were six (4%) failures requiring reoperation. Multivariate and comparative analysis demonstrated that the infant cohort utilized less morphine equivalents and more often had a percutaneous stent placed compared to the older cohort. Of the complications that occurred, 60% were minor (Clavien grades 1 and 2) and 40% were Clavien grade 3 in the infant cohort, and 70.1% and 29.9% in the older cohort, respectively. No studied criteria predicted failure in either cohort.

Pediatric Surgery International, Mar 29, 2018

Purpose We have retrospectively evaluated all patients who underwent endoscopic puncture (EP) of ... more Purpose We have retrospectively evaluated all patients who underwent endoscopic puncture (EP) of ureterocele over the last 26 years with special reference to the need in the second intervention and disease-free status. Methods 78 (69%) of the 112 patients following EP and completed follow-up were included. 51 (65%) were diagnosed prenatally and 27 (35%) postnatally. 46 patients (60%) had intravesical, while 32 (40%) had ectopic ureterocele. Median age at time of puncture was 4 months. Median time of the follow-up was 12 years (range 1-26 years), while 23 (30%) followed over 10 years and 15 (19%) completed adolescent period. Results Four children with ectopic ureterocele required secondary puncture. Ectopic ureterocele children had significantly more postoperative UTIs (13 (40%) ectopic vs 4 (19%) intravesical p = 0.047). 19 RRUs (44%) showed spontaneous resolution of VUR. 14 (18%) children required additional surgery: 7, endoscopic correction of VUR; 3, ureteral reimplantation and 4, partial nephrectomy. The need for additional surgery following puncture was higher in the group of children with ectopic ureterocele; however, this difference did not reach a statistical significance (p = 0.716). Conclusions Our data show that EP of ureterocele is a durable and long-term effective procedure in vast majority of the children.

Anaesthesia, 2021

SummaryPeri‐operative SARS‐CoV‐2 infection increases postoperative mortality. The aim of this stu... more SummaryPeri‐operative SARS‐CoV‐2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS‐CoV‐2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre‐operative SARS‐CoV‐2 infection were compared with those without previous SARS‐CoV‐2 infection. The primary outcome measure was 30‐day postoperative mortality. Logistic regression models were used to calculate adjusted 30‐day mortality rates stratified by time from diagnosis of SARS‐CoV‐2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre‐operative SARS‐CoV‐2 diagnosis. Adjusted 30‐day mortality in patients without SARS‐CoV‐2 infection was 1.5% (95%CI 1.4–1.5). In patients with a pre‐operative SARS‐CoV‐2 diagnosis, mortality was increased in patients having surgery wi...

Anaesthesia, 2021

SummarySARS‐CoV‐2 has been associated with an increased rate of venous thromboembolism in critica... more SummarySARS‐CoV‐2 has been associated with an increased rate of venous thromboembolism in critically ill patients. Since surgical patients are already at higher risk of venous thromboembolism than general populations, this study aimed to determine if patients with peri‐operative or prior SARS‐CoV‐2 were at further increased risk of venous thromboembolism. We conducted a planned sub‐study and analysis from an international, multicentre, prospective cohort study of elective and emergency patients undergoing surgery during October 2020. Patients from all surgical specialties were included. The primary outcome measure was venous thromboembolism (pulmonary embolism or deep vein thrombosis) within 30 days of surgery. SARS‐CoV‐2 diagnosis was defined as peri‐operative (7 days before to 30 days after surgery); recent (1–6 weeks before surgery); previous (≥7 weeks before surgery); or none. Information on prophylaxis regimens or pre‐operative anti‐coagulation for baseline comorbidities was no...

Journal of Pediatric Surgery, Aug 1, 2016

Objectives: We aimed to evaluate our experience with fenestrated sheet split-thickness skin graft... more Objectives: We aimed to evaluate our experience with fenestrated sheet split-thickness skin grafts (STSGs) in the pediatric population. Materials and methods: We retrospectively studied a cohort of 17 children 2-18 years old who underwent skin grafting owing to circumcision injuries (2 patients), traumatic penile injury (1) and after previous multiple hypospadias surgery (14). Fenestrated 0.012 in sheet STSGs from thigh area (15 patients) and buttock area (2) were fashioned to resurface the denuded penis following reconstruction. The median follow up was 13 years (range 1-19 years). Results: There was 94% take of the grafts. One patient required additional grafting following first graft infection. Six patients underwent concomitant surgery at the time of grafting (4 chordee repair and 2 meatoplasty). Two patients had slight chordee at 3 and 6 years postoperatively, and 2 with the history of preputial tubularized island flap hypospadias repair had developed a urethral stricture, which required staged repair with buccal mucosa 12 and 14 years following primary hypospadias repair. Six sexually active patients reported normal sexual intercourse and sensation following grafting. None of the patients demonstrated shrinkage of the STSGs over the follow up period. Conclusions: Our data demonstrated that the use of fenestrated sheet STSGs in patients with penile skin loss yields satisfactory functional and cosmetic outcomes. The buttocks might be considered as a preferable donor site in terms of avoiding a visible scar.

Urology, Jul 1, 2013

OBJECTIVE To evaluate the efficacy of Vantris in children with vesicoureteral reflux (VUR) after ... more OBJECTIVE To evaluate the efficacy of Vantris in children with vesicoureteral reflux (VUR) after 3 years of prospective follow-up. MATERIAL AND METHODS Over the last 3 years, 109 children (72 girls and 37 boys) with a mean age of 6.2 AE 3.4 years (mean AE SD) underwent endoscopic correction of reflux using Vantris. VUR was unilateral in 53 and bilateral in 56 patients comprising 165 renal refluxing units (RRUs). Of these, primary VUR was present in 139 RRUs (84.2%) and 26 (15.8%) were complex cases. Ultrasound scan was performed 1 month, 1 year, and 3 years after injection, and voiding cystourethrogram (VCUG) was performed 3 months, 1 year, and 3 years after endoscopic correction. RESULTS The reflux was corrected in 153 RRUs (92.7%) after a single injection and in 7 RRUs (4.2%) after a second injection. In 5 RRUs (3.1%), VUR downgraded to grade I (3 RRUs) and grade II (2 RRUs) and they were taken off antibiotic prophylaxis. Two patients (1.8%) had afebrile urinary tract infections (UTIs) and 2 patients (1.8%) developed febrile UTI. VCUG was performed in 32 of 71 children (39.1%) who completed 1 year and in 6 of 15 (40%) who completed 3 years of follow-up. None showed VUR recurrence. Ultrasound scan demonstrated normal appearance of kidneys in all but 2 patients (1.8%). One patient required stent insertion because of deterioration of hydronephrosis that resulted in complete resolution of obstruction and another patient required ureteral reimplantation. CONCLUSION Our data show that Vantris injection provides a high level of reflux resolution with good clinical outcome during prospective follow-up. UROLOGY-:-e-, 2013.

Advances in Urology, 2011

Purpose. We reviewed our 20 years of experience and the current literature regarding the long-ter... more Purpose. We reviewed our 20 years of experience and the current literature regarding the long-term outcome of endoscopic treatment of vesicoureteric reflux (VUR) using the different tissue bulking substances with a special emphasis on the long-term efficacy. Material and Methods. Our own experience and the current literature on the long-term results after endoscopic treatment using various bulking agents were reviewed. Results. Short-term data following endoscopic treatment of VUR is similar to the various substances and comparable in the majority of the series to the success rate following open surgery. Recently, a relatively high recurrence rate was noticed especially with the use of dextranomer hyaluronic acid (Dx/HA) as a tissue augmenting material which raises the need for further search for alternative substances. Conclusions. Unfortunately, there is a significant shortage of evidence-based literature on the long-term followup after endoscopic correction of reflux with various substances. No doubt, there is a high recurrence rate during long-term followup after Dx/HA injection, and there is probably lack of proper evaluation regarding the long-term efficacy of other bulking materials. These facts demand long-term close observation and long-term studies beyond the routine protocols following endoscopic treatment of VUR and the correct parental counseling upon the endoscopic correction.

Journal of Pediatric Urology, Jun 1, 2010

To determine the long-term effect in children of endoscopic treatment of vesicoureteral reflux (V... more To determine the long-term effect in children of endoscopic treatment of vesicoureteral reflux (VUR) using different bulking agents. VUR status, recurrence of urinary tract infection (UTI), and recurrence of febrile UTI were evaluated as endpoints. Methods: From 1993 to 2005, we injected 229 refluxive ureters (VUR grade IIeIV) in 135 children. Mean age of the children was 55.7 months. We used collagen in 98 (years 1993e2000), polydimethylsiloxane in 32 (years 1999e2000), and dextranomer/hyaluronic acid copolymer (Dx/HA) in 99 ureters (years 2000e2005). Of the 135 children, 127 underwent a voiding cystourethrogram (VCUG) (radiologic or nuclid) 3 months after the first injection, and 88 children a second VCUG (nuclid) after 37 months (mean) postoperatively. Clinically, patients were monitored for non-febrile or febrile UTI. Data were collected and analyzed retrospectively by chart review. Results: After first injection with collagen, polydimethysiloxane and Dx/HA, 52%, 55% and 81.5% of the children were without VUR, respectively. Repeated injections were successful in only 21% (collagen) to 42% (Dx/HA). Of the 88 with a second VCUG, 48.5% of the initially reflux-free children developed relapse VUR after collagen, 45.5% after polydimethylsiloxane and 21.5% after Dx/HA injection. Clinically, there was a significant difference in postoperative UTI occurrence in favor of the Dx/HA group. Conclusions: Clinically and radiologically, Dx/HA exhibited the best results, giving better protection against UTIs and a better VUR cure rate. There was still a risk of VUR recurrence in successfully treated children after 3 years of follow up.

The Journal of Urology, Oct 1, 2011

Purpose: Recently new approaches to laparoscopic surgery, named natural orifice transluminal endo... more Purpose: Recently new approaches to laparoscopic surgery, named natural orifice transluminal endoscopy and laparoendoscopic single site surgery, have been proposed to improve the cosmesis and decrease the morbidity associated with multiple ports sites. Experience with laparoendoscopic single site surgery technique in pediatric urology is still limited. We present our initial results with this technique in children. Materials and Methods: Since laparoendoscopic single site surgery received Food and Drug Administration approval, 11 patients have undergone a total of 14 procedures at our department, including nephrectomy due to nonfunctioning kidneys in 4, removal of bilateral intra-abdominal gonads in 2, unilateral varicocelectomy in 4 and bilateral varicocelectomy in 1. In all patients a multichannel single laparoscopic port inserted through a 2 cm skin incision was used to achieve access to the abdominal cavity. Results: All patients underwent laparoendoscopic single site surgery without complications within a reasonable operative time. None required conversion to open or conventional laparoscopic surgery. All except 1 patient were discharged home on the day of surgery or the day after surgery. Conclusions: Our initial data show that laparoendoscopic single site surgery is an effective technique for various pediatric and adolescent urology indications. Further application of this procedure in a large patient group will show whether there is a place for laparoendoscopic single site surgery in the pediatric urology surgical armamentarium.

World journal of clinical urology, 2014

Journal of Pediatric Urology, Dec 1, 2011

The aim of this study was to evaluate the efficacy of single injection of a new non-biodegradable... more The aim of this study was to evaluate the efficacy of single injection of a new non-biodegradable agent (Vantris Ò) Manufactured by Promedon, Cordoba, Argentina for treatment of vesicoureteric reflux (VUR). Patients and methods: 38 children (11 males and 27 females) with a mean age of 5.3 AE 3.8 years underwent endoscopic treatment of VUR using Vantris. VUR was unilateral in 17 and bilateral in 21 patients, comprising 59 renal refluxing units (RRU). The VUR was primary in 42 RRU and 17 comprised complex cases: 3 duplex systems, 1 with prune belly syndrome, and 13 after failed previous endoscopic correction with Deflux Ò. VUR was Grade I in 5, II in 11, III in 23, IV in 15 and V in 5 RRU. Results: All patients completed 3 months of follow up. The reflux was corrected in 56 (94.9%) of the 59 RRU (35/38 patients) after a single injection. Of the 38 patients, 21 completed 1 year of follow up, at which time ultrasound demonstrated no change compared with 1 month after injection. Eight of these 21 children underwent 1 year radionuclide cystography, and no reflux recurrence was shown. Conclusions: Our short-term data show that Vantris injection provides a high level of reflux resolution. Long-term follow up with this tissue-augmenting substance is required.

European Journal of Pediatric Surgery, Mar 16, 2015

Introduction We aimed to evaluate a novel technique for ureteric stent insertion during dismember... more Introduction We aimed to evaluate a novel technique for ureteric stent insertion during dismembered pediatric laparoscopic pyeloplasty. Patients and Methods Following identification and dissection of the ureteropelvic junction (UPJ) with the proximal part of ureter, the ureter is dismembered just proximal to the UPJ at the level of the renal pelvis, allowing use of the excess pelvic tissue for further manipulation of the ureter. Then the abdomen is desufflated and the ureter delivered to the skin level. The externalized ureter is then spatulated and the stent inserted in an antegrade fashion to the bladder. The first stitch for further laparoscopic anastomosis is applied to the lower part of the spatulated ureteric end and then following insufflations the ureter is returned to the abdomen. The laparoscopic anastomosis is completed in a routine fashion. Results Over the past 4 years, we have used this technique in 26 children (17 boys and 9 girls) with median age of 4 years (range, 2-18 years). Left pyeloplasty was performed in 16 and right pyeloplasty in the remaining 10 patients. The mean (range) time of insertion was 6 minutes (range, 4-7 minutes). All stents were correctly placed. In one patient, the stent dislodged to distal part of the ureter. No other intraoperative or postoperative complications related to our technique of stent insertion were observed. Conclusion Our data show that extracorporeal antegrade ureteric stent insertion is an easy-to-learn and a safe and reliable technique for pediatric dismembered pyeloplasty. It obviates the problem of having the stent in the pelvis during dissection and the need for patient repositioning.

Journal of Robotic Surgery, Apr 24, 2020

It has been suggested that up to 40 cases of RALP are required to reach the operative results equ... more It has been suggested that up to 40 cases of RALP are required to reach the operative results equal to open surgery. We have hypothesized that previous experience in open and laparoscopic surgeries might shorten the learning curve of robotic surgery. We have retrospectively evaluated the data of all children who underwent pyeloplasty in our institute by a single surgeon since 2003. The children were divided into three groups: open pyeloplasty (OP) of 72 children, laparoscopic pyeloplasty (LAP) of 22, and RALP of 33 patients subsequently. The data included: demographics, duration of surgery, length of stay, success of surgery, and complication rate according to the Clavien-Dindo score. The groups were ordered chronologically by the operation date and each group was divided into two different phases: early and late. A comparison was made between the data of the early and the late phase. There was no difference in the demographic data between the groups; however, the patients who underwent laparoscopic surgery were significantly older compared with the patients from the other groups. The median duration of surgery in the RALP group was significantly shorter than the OP group (65 min vs 72.5 min P < 0.01), while the first RALP case was already shorter than the median duration of surgery in OP group. There was no significant decrease in the duration of surgery of the RALP group over the study period, though there was a significant trend of decreasing operative time in the OP and LAP groups. There was no difference in the length of stay in the early vs late phases in the RALP group. There was no difference in the complication and success rate between the RALP and OP group, as well as the early and late phases of the RALP group. Our data show that previous experience in OP and LAP surgery may contribute to a shorter learning curve of robotic surgery required for the surgeon to achieve a similar outcome to that of OP.

Research Square (Research Square), Jul 19, 2022

Purpose: It has been suggested that symptomatic UA requires surgical excision. However, the manag... more Purpose: It has been suggested that symptomatic UA requires surgical excision. However, the management of asymptomatic urachus is still controversial. We aimed to evaluate the clinical presentation, the efficacy of current modalities used, and postoperative pathology in patients with UA. Material and Methods: We have performed a retrospective review of all patients diagnosed with UA and treated surgically or conservatively over 18 years. Demographic data, clinical presentation, imaging modalities, pathology, treatment, and postoperative complications were analyzed. Results: Twenty-five symptomatic patients (18 males and seven females) with a median age of 13 years (one month to 37 years) were identified. 15 (60%) were diagnosed with a urachal cyst, 4(16%) with sinus, 3(12%) with urachal diverticulum, and the remaining 3(12%) with patent urachus. Of those, 20(80%) underwent surgical repair, and the remaining five (20%) patients were managed conservatively. 4 (20%) underwent laparotomy, 7 (35%) laparoscopic incision, and the remaining 9 (45%) laparoscopic robotic-assisted surgery. Nine patients required bladder cuff excision. The median operative time was 75 minutes (42-140 min). One patient developed Clavien Dindo grade IIIA complication resulting in infected hematoma, which resolved after drainage. Another patient with a complication of grade IIIB needed reoperation as a result of recurrent events of an abscess. 13 (65%) demonstrated epithelium lining of the urachus on postoperative pathology.Conclusions: Our data show that most of the patients with UA presented with epithelial lining, which might lead to the later malignant transformation. It might cause a shift from the conservative management of asymptomatic patients to surgical intervention. Robotic-assisted surgery appears beneficial in these patients, especially when the bladder cuff excision is required.

Pediatric Surgery International, Apr 10, 2023

Journal of laparoendoscopic & advanced surgical techniques, Apr 1, 2021

The Journal of Urology, Apr 1, 2016

(CAP), with/without associated febrile urinary tract infection (UTI), and 6-weeks post-operativel... more (CAP), with/without associated febrile urinary tract infection (UTI), and 6-weeks post-operatively following open surgery; 2) respondents randomized to answer questions from child, parent, or dyad perspectives on the utility of a single VUR health state in an affected child; and 3) respondents randomized to answer questions from one of three practice scenarios (paralysis, common cold, none) prior to a VUR scenario. Utility estimates and potential predictors were fitted to a generalized linear model to determine what factors most impacted utilities. RESULTS: A total of 1,947 responses were obtained. Mean respondent age was 34-36 years; 48% were female; 37% were married; and 44% had children. Compared to a perfect health state of 1.0, mean VUR utility was 0.87 irrespective of CAP or UTI (p¼0.9). Utility values were uninfluenced by child/personal VUR/UTI history, income, or race. Utilities were higher in the child group (0.27 lower in parent v. child, p<0.001; 0.09 lower in dyad v. child, p<0.001), among single respondents (0.07 higher v. married, p¼0.007), and among older respondents (0.03 lower per 10-year age interval, p¼0.008). VUR utility was not significantly affected by the presence or type of TTO warm-up scenario (p¼0.87). CONCLUSIONS: Online crowd-sourced utility elicitation for pediatric urologic conditions is feasible. VUR utility was viewed as only slightly inferior to perfect health by most respondents.

Journal of Pediatric Urology, Dec 1, 2018

Background: It is extremely important to not only address the short-term success following endosc... more Background: It is extremely important to not only address the short-term success following endoscopic correction of vesicoureteral reflux (VUR) but also the long-term efficacy and safety of the tissue augmenting substance utilized for endoscopic correction. Objective: This study retrospectively evaluated all cases of ureterovesical junction (UVJ) obstruction following endoscopic treatment of VUR over the last 5 years utilizing two tissue augmenting substances, with special emphasis on the safety of Vantris ® , and performed clinical and histological review of these patients. Methods: The study population comprised 2495 patients who underwent endoscopic correction of VUR utilizing Deflux ® (1790) and Vantris ® (705). Tissue sections were stained with hematoxylin & eosin and trichrome, and examined under a light microscope. Nine primary obstructive megaureters after ureteral re-implantation served as controls. Results: Nine (0.5%) children (three female and six male) in the Deflux group and nine (1.3%) (five females and four males) in the Vantris group developed UVJ obstruction and required ureteral re-implantation. Obstruction developed during the period ranging 2-49 months (average 16 months) following endoscopic correction. The primary reflux grade was III in seven, IV in six, and V in six children. The mean volume of the injected material in all obstructed patients was 1.2±0.6 cc (mean±SD). Histopathological analysis revealed a pseudocapsule composed of fibrous tissue and foreign-body giant cells surrounding the Vantris implant in all patients. The distal part of the ureters demonstrated significant ureteral dilatation without ureteral fibrosis. In all patients, additional biopsies from the muscularis 3 Conclusion: Data showed that Vantris injection did not lead to any different ureteral fibrosis or inflammatory changes to the tissue augmenting substances utilized in past and present clinical practice, and therefore did not seem to increase the incidence of UVJ obstruction. High reflux grade, presence of obstructive/refluxing megaureter and inflamed bladder mucosa were the only statistically significant and independent predictive factors for UVJ obstruction following endoscopic correction of VUR.

Current Urology, Feb 1, 2014

To prospectively evaluate the efficacy of albumin glutaraldehyde tissue adhesive (BioGlue) in the... more To prospectively evaluate the efficacy of albumin glutaraldehyde tissue adhesive (BioGlue) in the surgical treatment of patients with hypospadias. Materials and Methods: Two groups of 20 patients each who underwent hypospadias repair were included in the study. In the first group we utilized BioGlue as an additional protective layer to the suture line of the neo-urethra, while patients in the second group were operated on utilizing a routine surgical technique. Results: There were no statistical differences between patients from the 2 groups in terms of surgical complications. Urethrocutaneous fistula was revealed in 4 (20%) patients after repair with BioGlue and in 3 (15%) patients from the control group (p = 0.686), suture line breakdown in 4 (20%) and in 1 (5%) patients (p = 0.478), meatal stenosis in 1 (5%) and in 1 (5%) patient (p = 1). Furthermore more patients in the BioGlue group (n = 12, 60%) demonstrated poor cosmetic results compared to the control group where most patients-19 (95%) had acceptable cosmetic outcomes (p = 0.007). Conclusions: Our data showed no benefits of BioGlue use in hypospadias repair.

Journal of Pediatric Urology, 2018

Background: Although shown to be safe in infancy, robotic-assisted laparoscopic pyeloplasty (RALP... more Background: Although shown to be safe in infancy, robotic-assisted laparoscopic pyeloplasty (RALP) for ureteropelvic junction obstruction (UPJO) is most commonly performed in older children and adolescents. Objective: This study examined a contemporary RALP experience at a single tertiary pediatric center and compared outcomes in infants aged ≤1 year with an older cohort. Methods and Design: All RALP procedures were entered into an Institutional Review Board-approved data registry from 2012-2016. Patients were retrospectively grouped according to age. The primary outcome was success rate. Secondary outcomes included complications and length of hospital stay. Failure was defined as the need for secondary surgical intervention for UPJO or worsening urinary tract dilation on imaging. Statistical analysis was performed using SPSS version 20. Mann-Whitney U testing was used for comparison. Results: A total of 138 patients underwent RALP during 2012-2016, with a median age of 6 years (IQR 1,13.25) and a male:female ratio of approximately 2:1. Of these, 34 (24.6%) were aged ≤1 year. Of all patients, 60 (43.5%) presented with a history of prenatal hydronephrosis, and 32% had a crossing vessel causing obstruction. An indwelling stent was placed in antegrade fashion in 71% of cases, and 18% had a percutaneously placed externalized stent. There were six (4%) failures requiring reoperation. Multivariate and comparative analysis demonstrated that the infant cohort utilized less morphine equivalents and more often had a percutaneous stent placed compared to the older cohort. Of the complications that occurred, 60% were minor (Clavien grades 1 and 2) and 40% were Clavien grade 3 in the infant cohort, and 70.1% and 29.9% in the older cohort, respectively. No studied criteria predicted failure in either cohort.

Pediatric Surgery International, Mar 29, 2018

Purpose We have retrospectively evaluated all patients who underwent endoscopic puncture (EP) of ... more Purpose We have retrospectively evaluated all patients who underwent endoscopic puncture (EP) of ureterocele over the last 26 years with special reference to the need in the second intervention and disease-free status. Methods 78 (69%) of the 112 patients following EP and completed follow-up were included. 51 (65%) were diagnosed prenatally and 27 (35%) postnatally. 46 patients (60%) had intravesical, while 32 (40%) had ectopic ureterocele. Median age at time of puncture was 4 months. Median time of the follow-up was 12 years (range 1-26 years), while 23 (30%) followed over 10 years and 15 (19%) completed adolescent period. Results Four children with ectopic ureterocele required secondary puncture. Ectopic ureterocele children had significantly more postoperative UTIs (13 (40%) ectopic vs 4 (19%) intravesical p = 0.047). 19 RRUs (44%) showed spontaneous resolution of VUR. 14 (18%) children required additional surgery: 7, endoscopic correction of VUR; 3, ureteral reimplantation and 4, partial nephrectomy. The need for additional surgery following puncture was higher in the group of children with ectopic ureterocele; however, this difference did not reach a statistical significance (p = 0.716). Conclusions Our data show that EP of ureterocele is a durable and long-term effective procedure in vast majority of the children.

Anaesthesia, 2021

SummaryPeri‐operative SARS‐CoV‐2 infection increases postoperative mortality. The aim of this stu... more SummaryPeri‐operative SARS‐CoV‐2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS‐CoV‐2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre‐operative SARS‐CoV‐2 infection were compared with those without previous SARS‐CoV‐2 infection. The primary outcome measure was 30‐day postoperative mortality. Logistic regression models were used to calculate adjusted 30‐day mortality rates stratified by time from diagnosis of SARS‐CoV‐2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre‐operative SARS‐CoV‐2 diagnosis. Adjusted 30‐day mortality in patients without SARS‐CoV‐2 infection was 1.5% (95%CI 1.4–1.5). In patients with a pre‐operative SARS‐CoV‐2 diagnosis, mortality was increased in patients having surgery wi...

Anaesthesia, 2021

SummarySARS‐CoV‐2 has been associated with an increased rate of venous thromboembolism in critica... more SummarySARS‐CoV‐2 has been associated with an increased rate of venous thromboembolism in critically ill patients. Since surgical patients are already at higher risk of venous thromboembolism than general populations, this study aimed to determine if patients with peri‐operative or prior SARS‐CoV‐2 were at further increased risk of venous thromboembolism. We conducted a planned sub‐study and analysis from an international, multicentre, prospective cohort study of elective and emergency patients undergoing surgery during October 2020. Patients from all surgical specialties were included. The primary outcome measure was venous thromboembolism (pulmonary embolism or deep vein thrombosis) within 30 days of surgery. SARS‐CoV‐2 diagnosis was defined as peri‐operative (7 days before to 30 days after surgery); recent (1–6 weeks before surgery); previous (≥7 weeks before surgery); or none. Information on prophylaxis regimens or pre‐operative anti‐coagulation for baseline comorbidities was no...

Journal of Pediatric Surgery, Aug 1, 2016

Objectives: We aimed to evaluate our experience with fenestrated sheet split-thickness skin graft... more Objectives: We aimed to evaluate our experience with fenestrated sheet split-thickness skin grafts (STSGs) in the pediatric population. Materials and methods: We retrospectively studied a cohort of 17 children 2-18 years old who underwent skin grafting owing to circumcision injuries (2 patients), traumatic penile injury (1) and after previous multiple hypospadias surgery (14). Fenestrated 0.012 in sheet STSGs from thigh area (15 patients) and buttock area (2) were fashioned to resurface the denuded penis following reconstruction. The median follow up was 13 years (range 1-19 years). Results: There was 94% take of the grafts. One patient required additional grafting following first graft infection. Six patients underwent concomitant surgery at the time of grafting (4 chordee repair and 2 meatoplasty). Two patients had slight chordee at 3 and 6 years postoperatively, and 2 with the history of preputial tubularized island flap hypospadias repair had developed a urethral stricture, which required staged repair with buccal mucosa 12 and 14 years following primary hypospadias repair. Six sexually active patients reported normal sexual intercourse and sensation following grafting. None of the patients demonstrated shrinkage of the STSGs over the follow up period. Conclusions: Our data demonstrated that the use of fenestrated sheet STSGs in patients with penile skin loss yields satisfactory functional and cosmetic outcomes. The buttocks might be considered as a preferable donor site in terms of avoiding a visible scar.

Urology, Jul 1, 2013

OBJECTIVE To evaluate the efficacy of Vantris in children with vesicoureteral reflux (VUR) after ... more OBJECTIVE To evaluate the efficacy of Vantris in children with vesicoureteral reflux (VUR) after 3 years of prospective follow-up. MATERIAL AND METHODS Over the last 3 years, 109 children (72 girls and 37 boys) with a mean age of 6.2 AE 3.4 years (mean AE SD) underwent endoscopic correction of reflux using Vantris. VUR was unilateral in 53 and bilateral in 56 patients comprising 165 renal refluxing units (RRUs). Of these, primary VUR was present in 139 RRUs (84.2%) and 26 (15.8%) were complex cases. Ultrasound scan was performed 1 month, 1 year, and 3 years after injection, and voiding cystourethrogram (VCUG) was performed 3 months, 1 year, and 3 years after endoscopic correction. RESULTS The reflux was corrected in 153 RRUs (92.7%) after a single injection and in 7 RRUs (4.2%) after a second injection. In 5 RRUs (3.1%), VUR downgraded to grade I (3 RRUs) and grade II (2 RRUs) and they were taken off antibiotic prophylaxis. Two patients (1.8%) had afebrile urinary tract infections (UTIs) and 2 patients (1.8%) developed febrile UTI. VCUG was performed in 32 of 71 children (39.1%) who completed 1 year and in 6 of 15 (40%) who completed 3 years of follow-up. None showed VUR recurrence. Ultrasound scan demonstrated normal appearance of kidneys in all but 2 patients (1.8%). One patient required stent insertion because of deterioration of hydronephrosis that resulted in complete resolution of obstruction and another patient required ureteral reimplantation. CONCLUSION Our data show that Vantris injection provides a high level of reflux resolution with good clinical outcome during prospective follow-up. UROLOGY-:-e-, 2013.

Advances in Urology, 2011

Purpose. We reviewed our 20 years of experience and the current literature regarding the long-ter... more Purpose. We reviewed our 20 years of experience and the current literature regarding the long-term outcome of endoscopic treatment of vesicoureteric reflux (VUR) using the different tissue bulking substances with a special emphasis on the long-term efficacy. Material and Methods. Our own experience and the current literature on the long-term results after endoscopic treatment using various bulking agents were reviewed. Results. Short-term data following endoscopic treatment of VUR is similar to the various substances and comparable in the majority of the series to the success rate following open surgery. Recently, a relatively high recurrence rate was noticed especially with the use of dextranomer hyaluronic acid (Dx/HA) as a tissue augmenting material which raises the need for further search for alternative substances. Conclusions. Unfortunately, there is a significant shortage of evidence-based literature on the long-term followup after endoscopic correction of reflux with various substances. No doubt, there is a high recurrence rate during long-term followup after Dx/HA injection, and there is probably lack of proper evaluation regarding the long-term efficacy of other bulking materials. These facts demand long-term close observation and long-term studies beyond the routine protocols following endoscopic treatment of VUR and the correct parental counseling upon the endoscopic correction.

Journal of Pediatric Urology, Jun 1, 2010

To determine the long-term effect in children of endoscopic treatment of vesicoureteral reflux (V... more To determine the long-term effect in children of endoscopic treatment of vesicoureteral reflux (VUR) using different bulking agents. VUR status, recurrence of urinary tract infection (UTI), and recurrence of febrile UTI were evaluated as endpoints. Methods: From 1993 to 2005, we injected 229 refluxive ureters (VUR grade IIeIV) in 135 children. Mean age of the children was 55.7 months. We used collagen in 98 (years 1993e2000), polydimethylsiloxane in 32 (years 1999e2000), and dextranomer/hyaluronic acid copolymer (Dx/HA) in 99 ureters (years 2000e2005). Of the 135 children, 127 underwent a voiding cystourethrogram (VCUG) (radiologic or nuclid) 3 months after the first injection, and 88 children a second VCUG (nuclid) after 37 months (mean) postoperatively. Clinically, patients were monitored for non-febrile or febrile UTI. Data were collected and analyzed retrospectively by chart review. Results: After first injection with collagen, polydimethysiloxane and Dx/HA, 52%, 55% and 81.5% of the children were without VUR, respectively. Repeated injections were successful in only 21% (collagen) to 42% (Dx/HA). Of the 88 with a second VCUG, 48.5% of the initially reflux-free children developed relapse VUR after collagen, 45.5% after polydimethylsiloxane and 21.5% after Dx/HA injection. Clinically, there was a significant difference in postoperative UTI occurrence in favor of the Dx/HA group. Conclusions: Clinically and radiologically, Dx/HA exhibited the best results, giving better protection against UTIs and a better VUR cure rate. There was still a risk of VUR recurrence in successfully treated children after 3 years of follow up.

The Journal of Urology, Oct 1, 2011

Purpose: Recently new approaches to laparoscopic surgery, named natural orifice transluminal endo... more Purpose: Recently new approaches to laparoscopic surgery, named natural orifice transluminal endoscopy and laparoendoscopic single site surgery, have been proposed to improve the cosmesis and decrease the morbidity associated with multiple ports sites. Experience with laparoendoscopic single site surgery technique in pediatric urology is still limited. We present our initial results with this technique in children. Materials and Methods: Since laparoendoscopic single site surgery received Food and Drug Administration approval, 11 patients have undergone a total of 14 procedures at our department, including nephrectomy due to nonfunctioning kidneys in 4, removal of bilateral intra-abdominal gonads in 2, unilateral varicocelectomy in 4 and bilateral varicocelectomy in 1. In all patients a multichannel single laparoscopic port inserted through a 2 cm skin incision was used to achieve access to the abdominal cavity. Results: All patients underwent laparoendoscopic single site surgery without complications within a reasonable operative time. None required conversion to open or conventional laparoscopic surgery. All except 1 patient were discharged home on the day of surgery or the day after surgery. Conclusions: Our initial data show that laparoendoscopic single site surgery is an effective technique for various pediatric and adolescent urology indications. Further application of this procedure in a large patient group will show whether there is a place for laparoendoscopic single site surgery in the pediatric urology surgical armamentarium.

World journal of clinical urology, 2014

Journal of Pediatric Urology, Dec 1, 2011

The aim of this study was to evaluate the efficacy of single injection of a new non-biodegradable... more The aim of this study was to evaluate the efficacy of single injection of a new non-biodegradable agent (Vantris Ò) Manufactured by Promedon, Cordoba, Argentina for treatment of vesicoureteric reflux (VUR). Patients and methods: 38 children (11 males and 27 females) with a mean age of 5.3 AE 3.8 years underwent endoscopic treatment of VUR using Vantris. VUR was unilateral in 17 and bilateral in 21 patients, comprising 59 renal refluxing units (RRU). The VUR was primary in 42 RRU and 17 comprised complex cases: 3 duplex systems, 1 with prune belly syndrome, and 13 after failed previous endoscopic correction with Deflux Ò. VUR was Grade I in 5, II in 11, III in 23, IV in 15 and V in 5 RRU. Results: All patients completed 3 months of follow up. The reflux was corrected in 56 (94.9%) of the 59 RRU (35/38 patients) after a single injection. Of the 38 patients, 21 completed 1 year of follow up, at which time ultrasound demonstrated no change compared with 1 month after injection. Eight of these 21 children underwent 1 year radionuclide cystography, and no reflux recurrence was shown. Conclusions: Our short-term data show that Vantris injection provides a high level of reflux resolution. Long-term follow up with this tissue-augmenting substance is required.

European Journal of Pediatric Surgery, Mar 16, 2015

Introduction We aimed to evaluate a novel technique for ureteric stent insertion during dismember... more Introduction We aimed to evaluate a novel technique for ureteric stent insertion during dismembered pediatric laparoscopic pyeloplasty. Patients and Methods Following identification and dissection of the ureteropelvic junction (UPJ) with the proximal part of ureter, the ureter is dismembered just proximal to the UPJ at the level of the renal pelvis, allowing use of the excess pelvic tissue for further manipulation of the ureter. Then the abdomen is desufflated and the ureter delivered to the skin level. The externalized ureter is then spatulated and the stent inserted in an antegrade fashion to the bladder. The first stitch for further laparoscopic anastomosis is applied to the lower part of the spatulated ureteric end and then following insufflations the ureter is returned to the abdomen. The laparoscopic anastomosis is completed in a routine fashion. Results Over the past 4 years, we have used this technique in 26 children (17 boys and 9 girls) with median age of 4 years (range, 2-18 years). Left pyeloplasty was performed in 16 and right pyeloplasty in the remaining 10 patients. The mean (range) time of insertion was 6 minutes (range, 4-7 minutes). All stents were correctly placed. In one patient, the stent dislodged to distal part of the ureter. No other intraoperative or postoperative complications related to our technique of stent insertion were observed. Conclusion Our data show that extracorporeal antegrade ureteric stent insertion is an easy-to-learn and a safe and reliable technique for pediatric dismembered pyeloplasty. It obviates the problem of having the stent in the pelvis during dissection and the need for patient repositioning.

Journal of Robotic Surgery, Apr 24, 2020

It has been suggested that up to 40 cases of RALP are required to reach the operative results equ... more It has been suggested that up to 40 cases of RALP are required to reach the operative results equal to open surgery. We have hypothesized that previous experience in open and laparoscopic surgeries might shorten the learning curve of robotic surgery. We have retrospectively evaluated the data of all children who underwent pyeloplasty in our institute by a single surgeon since 2003. The children were divided into three groups: open pyeloplasty (OP) of 72 children, laparoscopic pyeloplasty (LAP) of 22, and RALP of 33 patients subsequently. The data included: demographics, duration of surgery, length of stay, success of surgery, and complication rate according to the Clavien-Dindo score. The groups were ordered chronologically by the operation date and each group was divided into two different phases: early and late. A comparison was made between the data of the early and the late phase. There was no difference in the demographic data between the groups; however, the patients who underwent laparoscopic surgery were significantly older compared with the patients from the other groups. The median duration of surgery in the RALP group was significantly shorter than the OP group (65 min vs 72.5 min P < 0.01), while the first RALP case was already shorter than the median duration of surgery in OP group. There was no significant decrease in the duration of surgery of the RALP group over the study period, though there was a significant trend of decreasing operative time in the OP and LAP groups. There was no difference in the length of stay in the early vs late phases in the RALP group. There was no difference in the complication and success rate between the RALP and OP group, as well as the early and late phases of the RALP group. Our data show that previous experience in OP and LAP surgery may contribute to a shorter learning curve of robotic surgery required for the surgeon to achieve a similar outcome to that of OP.

Research Square (Research Square), Jul 19, 2022

Purpose: It has been suggested that symptomatic UA requires surgical excision. However, the manag... more Purpose: It has been suggested that symptomatic UA requires surgical excision. However, the management of asymptomatic urachus is still controversial. We aimed to evaluate the clinical presentation, the efficacy of current modalities used, and postoperative pathology in patients with UA. Material and Methods: We have performed a retrospective review of all patients diagnosed with UA and treated surgically or conservatively over 18 years. Demographic data, clinical presentation, imaging modalities, pathology, treatment, and postoperative complications were analyzed. Results: Twenty-five symptomatic patients (18 males and seven females) with a median age of 13 years (one month to 37 years) were identified. 15 (60%) were diagnosed with a urachal cyst, 4(16%) with sinus, 3(12%) with urachal diverticulum, and the remaining 3(12%) with patent urachus. Of those, 20(80%) underwent surgical repair, and the remaining five (20%) patients were managed conservatively. 4 (20%) underwent laparotomy, 7 (35%) laparoscopic incision, and the remaining 9 (45%) laparoscopic robotic-assisted surgery. Nine patients required bladder cuff excision. The median operative time was 75 minutes (42-140 min). One patient developed Clavien Dindo grade IIIA complication resulting in infected hematoma, which resolved after drainage. Another patient with a complication of grade IIIB needed reoperation as a result of recurrent events of an abscess. 13 (65%) demonstrated epithelium lining of the urachus on postoperative pathology.Conclusions: Our data show that most of the patients with UA presented with epithelial lining, which might lead to the later malignant transformation. It might cause a shift from the conservative management of asymptomatic patients to surgical intervention. Robotic-assisted surgery appears beneficial in these patients, especially when the bladder cuff excision is required.

Pediatric Surgery International, Apr 10, 2023

Journal of laparoendoscopic & advanced surgical techniques, Apr 1, 2021

The Journal of Urology, Apr 1, 2016

(CAP), with/without associated febrile urinary tract infection (UTI), and 6-weeks post-operativel... more (CAP), with/without associated febrile urinary tract infection (UTI), and 6-weeks post-operatively following open surgery; 2) respondents randomized to answer questions from child, parent, or dyad perspectives on the utility of a single VUR health state in an affected child; and 3) respondents randomized to answer questions from one of three practice scenarios (paralysis, common cold, none) prior to a VUR scenario. Utility estimates and potential predictors were fitted to a generalized linear model to determine what factors most impacted utilities. RESULTS: A total of 1,947 responses were obtained. Mean respondent age was 34-36 years; 48% were female; 37% were married; and 44% had children. Compared to a perfect health state of 1.0, mean VUR utility was 0.87 irrespective of CAP or UTI (p¼0.9). Utility values were uninfluenced by child/personal VUR/UTI history, income, or race. Utilities were higher in the child group (0.27 lower in parent v. child, p<0.001; 0.09 lower in dyad v. child, p<0.001), among single respondents (0.07 higher v. married, p¼0.007), and among older respondents (0.03 lower per 10-year age interval, p¼0.008). VUR utility was not significantly affected by the presence or type of TTO warm-up scenario (p¼0.87). CONCLUSIONS: Online crowd-sourced utility elicitation for pediatric urologic conditions is feasible. VUR utility was viewed as only slightly inferior to perfect health by most respondents.

Journal of Pediatric Urology, Dec 1, 2018

Background: It is extremely important to not only address the short-term success following endosc... more Background: It is extremely important to not only address the short-term success following endoscopic correction of vesicoureteral reflux (VUR) but also the long-term efficacy and safety of the tissue augmenting substance utilized for endoscopic correction. Objective: This study retrospectively evaluated all cases of ureterovesical junction (UVJ) obstruction following endoscopic treatment of VUR over the last 5 years utilizing two tissue augmenting substances, with special emphasis on the safety of Vantris ® , and performed clinical and histological review of these patients. Methods: The study population comprised 2495 patients who underwent endoscopic correction of VUR utilizing Deflux ® (1790) and Vantris ® (705). Tissue sections were stained with hematoxylin & eosin and trichrome, and examined under a light microscope. Nine primary obstructive megaureters after ureteral re-implantation served as controls. Results: Nine (0.5%) children (three female and six male) in the Deflux group and nine (1.3%) (five females and four males) in the Vantris group developed UVJ obstruction and required ureteral re-implantation. Obstruction developed during the period ranging 2-49 months (average 16 months) following endoscopic correction. The primary reflux grade was III in seven, IV in six, and V in six children. The mean volume of the injected material in all obstructed patients was 1.2±0.6 cc (mean±SD). Histopathological analysis revealed a pseudocapsule composed of fibrous tissue and foreign-body giant cells surrounding the Vantris implant in all patients. The distal part of the ureters demonstrated significant ureteral dilatation without ureteral fibrosis. In all patients, additional biopsies from the muscularis 3 Conclusion: Data showed that Vantris injection did not lead to any different ureteral fibrosis or inflammatory changes to the tissue augmenting substances utilized in past and present clinical practice, and therefore did not seem to increase the incidence of UVJ obstruction. High reflux grade, presence of obstructive/refluxing megaureter and inflamed bladder mucosa were the only statistically significant and independent predictive factors for UVJ obstruction following endoscopic correction of VUR.

Current Urology, Feb 1, 2014

To prospectively evaluate the efficacy of albumin glutaraldehyde tissue adhesive (BioGlue) in the... more To prospectively evaluate the efficacy of albumin glutaraldehyde tissue adhesive (BioGlue) in the surgical treatment of patients with hypospadias. Materials and Methods: Two groups of 20 patients each who underwent hypospadias repair were included in the study. In the first group we utilized BioGlue as an additional protective layer to the suture line of the neo-urethra, while patients in the second group were operated on utilizing a routine surgical technique. Results: There were no statistical differences between patients from the 2 groups in terms of surgical complications. Urethrocutaneous fistula was revealed in 4 (20%) patients after repair with BioGlue and in 3 (15%) patients from the control group (p = 0.686), suture line breakdown in 4 (20%) and in 1 (5%) patients (p = 0.478), meatal stenosis in 1 (5%) and in 1 (5%) patient (p = 1). Furthermore more patients in the BioGlue group (n = 12, 60%) demonstrated poor cosmetic results compared to the control group where most patients-19 (95%) had acceptable cosmetic outcomes (p = 0.007). Conclusions: Our data showed no benefits of BioGlue use in hypospadias repair.