Genomic copy number variation association study in Caucasian patients with nonsyndromic cryptorchidism.

BACKGROUND: Copy number variation (CNV) is a potential contributing factor to many genetic diseases. Here we investigated the potential association of CNV with nonsyndromic cryptorchidism, the most common male congenital genitourinary defect, in a Caucasian population. METHODS: Genome wide genotyping were performed in 559 cases and 1772 controls (Group 1) using Illumina HumanHap550 v1, HumanHap550 v3 or Human610-Quad platforms and in 353 cases and 1149 controls (Group 2) using the Illumina Human OmniExpress 12v1 or Human OmniExpress 12v1-1. Signal intensity data including log R ratio (LRR) and B allele frequency (BAF) for each single nucleotide polymorphism (SNP) were used for CNV detection using PennCNV software. After sample quality control, gene- and CNV-based association tests were performed using cleaned data from Group 1 (493 cases and 1586 controls) and Group 2 (307 cases and 1102 controls) using ParseCNV software. Meta-analysis was performed using gene-based test results as input to identify significant genes, and CNVs in or around significant genes were identified in CNV-based association test results. Called CNVs passing quality control and signal intensity visualization examination were considered for validation using TaqMan CNV assays and QuantStudio® 3D Digital PCR System. RESULTS: The meta-analysis identified 373 genome wide significant (p < 5X10-4) genes/loci including 49 genes/loci with deletions and 324 with duplications. Among them, 17 genes with deletion and 1 gene with duplication were identified in CNV-based association results in both Group 1 and Group 2. Only 2 genes (NUCB2 and UPF2) containing deletions passed CNV quality control in both groups and signal intensity visualization examination, but laboratory validation failed to verify these deletions. CONCLUSIONS: Our data do not support that structural variation is a major cause of nonsyndromic cryptorchidism.

Phenotype specific association of the TGFBR3 locus with nonsyndromic cryptorchidism.

PURPOSE: Based on a genome-wide association study of testicular dysgenesis syndrome showing a possible association with TGFBR3, we analyzed data from a larger, phenotypically restricted cryptorchidism population for potential replication of this signal. MATERIALS AND METHODS: We excluded samples based on strict quality control criteria, leaving 844 cases and 2,718 controls of European ancestry that were analyzed in 2 separate groups based on genotyping platform (ie Illumina® HumanHap550, version 1 or 3, or Human610-Quad, version 1 BeadChip in group 1 and Human OmniExpress 12, version 1 BeadChip platform in group 2). Analyses included genotype imputation at the TGFBR3 locus, association analysis of imputed data with correction for population substructure, subsequent meta-analysis of data for groups 1 and 2, and selective genotyping of independent cases (330) and controls (324) for replication. We also measured Tgfbr3 mRNA levels and performed TGFBR3/betaglycan immunostaining in rat fetal gubernaculum. RESULTS: We identified suggestive (p ≤ 1× 10(-4)) association of markers in/near TGFBR3, including rs9661103 (OR 1.40; 95% CI 1.20, 1.64; p = 2.71 × 10(-5)) and rs10782968 (OR 1.58; 95% CI 1.26, 1.98; p = 9.36 × 10(-5)) in groups 1 and 2, respectively. In subgroup analyses we observed strongest association of rs17576372 (OR 1.42; 95% CI 1.24, 1.60; p = 1.67 × 10(-4)) with proximal and rs11165059 (OR 1.32; 95% CI 1.15, 1.38; p = 9.42 × 10(-4)) with distal testis position, signals in strong linkage disequilibrium with rs9661103 and rs10782968, respectively. Association of the prior genome-wide association study signal (rs12082710) was marginal (OR 1.13; 95% CI 0.99, 1.28; p = 0.09 for group 1), and we were unable to replicate signals in our independent cohort. Tgfbr3/betaglycan was differentially expressed in wild-type and cryptorchid rat fetal gubernaculum. CONCLUSIONS: These data suggest complex or phenotype specific association of cryptorchidism with TGFBR3 and the gubernaculum as a potential target of TGFß signaling.

Pathway analysis supports association of nonsyndromic cryptorchidism with genetic loci linked to cytoskeleton-dependent functions.

STUDY QUESTION: What are the genetic loci that increase susceptibility to nonsyndromic cryptorchidism, or undescended testis? SUMMARY ANSWER: A genome-wide association study (GWAS) suggests that susceptibility to cryptorchidism is heterogeneous, with a subset of suggestive signals linked to cytoskeleton-dependent functions and syndromic forms of the disease. WHAT IS KNOWN ALREADY: Population studies suggest moderate genetic risk of cryptorchidism and possible maternal and environmental contributions to risk. Previous candidate gene analyses have failed to identify a major associated locus, although variants in insulin-like 3 (INSL3), relaxin/insulin-like family peptide receptor 2 (RXFP2) and other hormonal pathway genes may increase risk in a small percentage of patients. STUDY DESIGN, SIZE, DURATION: This is a case-control GWAS of 844 boys with nonsyndromic cryptorchidism and 2718 control subjects without syndromes or genital anomalies, all of European ancestry. PARTICIPANTS/MATERIALS, SETTING, METHODS: All boys with cryptorchidism were diagnosed and treated by a pediatric specialist. In the discovery phase, DNA was extracted from tissue or blood samples and genotyping performed using the Illumina HumanHap550 and Human610-Quad (Group 1) or OmniExpress (Group 2) platform. We imputed genotypes genome-wide, and combined single marker association results in meta-analyses for all cases and for secondary subphenotype analyses based on testis position, laterality and age, and defined genome-wide significance as P = 7 × 10(-9) to correct for multiple testing. Selected markers were genotyped in an independent replication group of European cases (n = 298) and controls (n = 324). We used several bioinformatics tools to analyze top (P < 10(-5)) and suggestive (P < 10(-3)) signals for significant enrichment of signaling pathways, cellular functions and custom gene lists after multiple testing correction. MAIN RESULTS AND THE ROLE OF CHANCE: In the full analysis, we identified 20 top loci, none reaching genome-wide significance, but one passing this threshold in a subphenotype analysis of proximal testis position (rs55867206, near SH3PXD2B, odds ratio = 2.2 (95% confidence interval 1.7, 2.9), P = 2 × 10(-9)). An additional 127 top loci emerged in at least one secondary analysis, particularly of more severe phenotypes. Cytoskeleton-dependent molecular and cellular functions were prevalent in pathway analysis of suggestive signals, and may implicate loci encoding cytoskeletal proteins that participate in androgen receptor signaling. Genes linked to human syndromic cryptorchidism, including hypogonadotropic hypogonadism, and to hormone-responsive and/or differentially expressed genes in normal and cryptorchid rat gubernaculum, were also significantly overrepresented. No tested marker showed significant replication in an independent population. The results suggest heterogeneous, multilocus and potentially multifactorial susceptibility to nonsyndromic cryptorchidism. LIMITATIONS, REASONS FOR CAUTION: The present study failed to identify genome-wide significant markers associated with cryptorchidism that could be replicated in an independent population, so further studies are required to define true positive signals among suggestive loci. WIDER IMPLICATIONS OF THE FINDINGS: As the only GWAS to date of nonsyndromic cryptorchidism, these data will provide a basis for future efforts to understand genetic susceptibility to this common reproductive anomaly and the potential for additive risk from environmental exposures. STUDY FUNDING/COMPETING INTERESTS: This work was supported by R01HD060769 (the Eunice Kennedy Shriver National Institute for Child Health and Human Development (NICHD)), P20RR20173 (the National Center for Research Resources (NCRR), currently P20GM103464 from the National Institute of General Medical Sciences (NIGMS)), an Institute Development Fund to the Center for Applied Genomics at The Children's Hospital of Philadelphia, and Nemours Biomedical Research. The authors have no competing interests to declare.

Spinal versus general anesthesia: Comparing outcomes in pediatric patients undergoing urologic procedures.

INTRODUCTION: Available literature comparing spinal anesthesia (SA) to general anesthesia (GA) in the pediatric population describes multiple benefits in appropriately selected patients including cost reduction, lower incidence of complications, and shorter operative times. In patients undergoing urologic procedures, data are sparse. OBJECTIVE: Our goal was to expand on the paucity of existing urologic literature as SA appears to be uniquely suited for a substantial number of its common pediatric procedures. METHODS: Within a single institution, patients who had a urologic procedure performed under SA between May 2019 and July 2021 and were less than 18 months old were compared with a matched cohort of patients who had GA. The SA and GA groups were compared by two-sample t-tests, chi-square test for independence, and Fisher's exact test. RESULTS: There were a total of 184 SA and 202 GA patients. There was no significant difference in the demographics except that SA patients were younger and weighed less than GA patients. The patients in the SA group needed less opioids both during the surgery (0% vs 26.1% p N/A) and in the immediate postoperative period when compared with GA patients (0% vs 18.2% p N/A). The patients who had SA had fewer complications necessitating PICU admission, or cancellation of surgery (0% vs 6.8% p = 0.03). Total anesthesia and emergence time were lower for SA patients (41 vs 50.2 p = 0.001 & 3.4 vs 6.1 p = 0.001). Both surgery and total OR time were not different between the groups (37.6 vs 35.5 p = 0.35 and 56.3 vs 54.4 p = 0.49). Overall, raw material cost was also found to be lower per procedure in the SA group vs the GA group ($8.90 vs $38.8: 77% reduction). Adjusted total mean costs for the surgery were not different between groups. The reduction in opioid use postoperatively also suggests reduced cost in the management of postoperative pain in the SA group. DISCUSSION: Total anesthesia time, opioid use, and serious complications were all significantly lower in the SA group. We did not find significant difference in total surgery cost between two groups. However, patients who had SA had better pain control and needed less rescue analgesics in the immediate postoperative period. No patients in either group were sent home with opioids. CONCLUSION: Spinal anesthesia was found to be an equally effective and appropriate alternative to GA with many proposed benefits for common pediatric urologic procedures. With further research, SA may prove to be a safer alternative in patients at risk for complications related to GA general anesthesia while also offering a cost benefit.

Reduced expression of androgen receptor and myosin heavy chain mRNA in cremaster muscle of boys with nonsyndromic cryptorchidism.

PURPOSE: To better define the developmental mechanisms of nonsyndromic cryptorchidism, we measured the expression of hormone receptor and muscle type specific mRNAs in target tissues of boys with and those without nonsyndromic cryptorchidism. MATERIALS AND METHODS: Prospectively collected cremaster muscle and/or hernia sac tissues from boys with congenital (79) or acquired (66) nonsyndromic cryptorchidism and hernia/hydrocele (controls, 84) were analyzed for hormone receptor (RXFP2, AR, ESR1, ESR2) and myosin heavy chain specific (MYH1, MYH2, MYH7) mRNA expression using real-time reverse transcriptase polymerase chain reaction. Log transformed mRNA, phenotype and feeding history data were statistically analyzed using Pearson's correlation, ANOVA and 2-sample t tests. RESULTS: AR mRNA expression was higher in cremaster muscle than in sac tissue, and significantly lower in congenital and acquired nonsyndromic cryptorchidism cases vs controls (p <0.01). Type 1 (slow/cardiac) MYH7 mRNA expression was also significantly reduced in both nonsyndromic cryptorchidism groups (p ≤ 0.002), while a reduction in type 2 (fast) MYH2 expression was more modest and significant only for the congenital cryptorchidism group (p <0.05). Cremasteric MYH7 and AR levels were strongly correlated (r(2) = 0.751, p <0.001). MYH7 and ESR1 mRNA levels were higher and lower, respectively, in boys with nonsyndromic cryptorchidism who were fed soy formula. Expression of other genes was not measurable. CONCLUSIONS: Our data suggest that boys with congenital and acquired nonsyndromic cryptorchidism differentially express AR and slow twitch specific MYH7 mRNA in the cremaster muscle, and that MYH7 expression is correlated with AR levels and soy formula use. These differences in gene expression may reflect aberrant hormonal signaling and/or innervation during development with the potential for secondary functional effects and failed testicular descent.

Altered infant feeding patterns in boys with acquired nonsyndromic cryptorchidism.

BACKGROUND: Genetic and environmental factors likely influence susceptibility to nonsyndromic cryptorchidism, a common disease presenting at birth or in later childhood. We compared cases and controls to define differential risk factors for congenital versus acquired cryptorchidism. METHODS: We compared questionnaire and clinical data from cases of congenital cryptorchidism (n = 230), acquired cryptorchidism (n = 182) and hernia/hydrocele (n = 104) with a group of healthy male controls (n = 358). Potential predictor variables (p < 0.2 in univariable analysis) were included in stepwise multivariable logistic regression models. RESULTS: Temporary (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.4-0.8) or exclusive (OR, 0.6; 95% CI, 0.4-0.9) breastfeeding was reduced and soy formula feeding increased (OR, 1.8; 95% CI, 1.2-2.9) in acquired but not congenital or hernia/hydrocele groups. The highest risk estimates were observed for primary soy formula feeding with limited or no breastfeeding (OR 2.5; 95% CI, 1.4-4.3; adjusted OR, 2.7; 95% CI, 1.4-5.4) in the acquired group. Primary feeding risk estimates were equivalent or strengthened when multivariable models were limited to age greater than 2 years, full-term or not small for gestational age, or Caucasian subjects. Pregnancy complications and increased maternal exposure to cosmetic or household chemicals were not consistently associated with either form of cryptorchidism in these models. CONCLUSIONS: Our data support reduced breastfeeding and soy formula feeding as potential risk factors for acquired cryptorchidism. Although additional studies are needed, hormonally active components of breast milk and soy formula could influence the establishment of normal testis position in the first months of life, leading to apparent ascent of testes in childhood. Birth Defects Research (Part A), 2012.

The Need for Improved Detection of Urinary Tract Infections in Young Children.

BACKGROUND AND OBJECTIVES: An estimated 400,000 urinary tract infections (UTIs) are diagnosed annually in children aged <3 years in the United States; yet >50% of febrile UTIs may be missed in this population. Here, we explored possible barriers to diagnosing febrile UTIs in very young children through social research of community pediatricians. METHODS: Following qualitative interviews, a quantitative survey was developed that included a high-risk case for febrile UTI, presented before prompting for the topic of the survey, to gauge practice of delayed testing. Factors associated with delay were explored using univariate logistic regression. The final survey link was sent to three populations via email, with the largest response from a survey sent to pediatricians in Pennsylvania, which formed the basis of our primary results. RESULTS: Of the 218 evaluable responses, 59.6% of physicians would initially test urine in the high-risk case patient, while 21.6% would choose to continue fever reducer and follow-up in 2 days. In the knowledge-based questions, 67.5, 34.0, and 35.6% of respondents identified the correct prevalences in total population, Caucasian girls, and uncircumcised boys, respectively. Many pediatricians (59.5%) believed that delays in detection are common in clinical practice. Physicians who chose to delay testing were more likely to be female, in practice for <25 years, to underestimate prevalence of febrile UTIs and have greater number of children seen per week (all P ≤ 0.02). CONCLUSION: Our findings support the need for improved communication and education about prevalence in higher risk populations, outcomes associated with delayed diagnosis, and optimal skills for collection of urine in young patients.

Analyte variations in consecutive 24-hour urine collections in children.

PURPOSE: The metabolic evaluation of children with nephrolithiasis begins with a 24-h urine collection. For adults, the diagnostic yield increases with consecutive collections; however, little is known regarding the variability of multiple 24-h studies in the pediatric population. We sought to evaluate the variability of consecutive 24-h urine collection in children through a multi-institutional study hypothesizing that compared with a single collection, consecutive 24-h urine collections would reveal a greater degree of clinically useful information in the evaluation of children at risk for nephrolithiasis. MATERIALS AND METHODS: Including data from six institutions, we identified children less than 18 years of age considered at risk for recurrent nephrolithiasis, undergoing metabolic evaluation. We evaluated a subset of patients performing two collections with urine creatinine varying by 10% or less during a 7-day period. Discordance between repeat collections based on normative urine chemistry values was evaluated. RESULTS: A total of 733 children met inclusion criteria, and in over a third both urine calcium and urine volume differed by 30% or more between samples. Urine oxalate demonstrated greater variation between collections in children <5 years than among older children (p = 0.030) while variation in other parameters did not differ by age. Discordance between repeat samples based on normative values was most common for urine oxalate (22.5%) and the derived relative supersaturation ratios for both calcium phosphate (25.1%) and calcium oxalate (20.5%). The proportion of discordant samples, based on normative thresholds, as well as variability greater ≥30% and 50%, respectively, are shown in the table. CONCLUSIONS: Our analysis indicates that stone risk in as many as one in four children may be misclassified if normative values of only a single 24-h urine are used. In light of these findings, repeat 24-h urine collections prior to targeted intervention to modify stone risk are advised to increase diagnostic yield in children at risk for nephrolithiasis.

Comparison of dismembered and nondismembered laparoscopic pyeloplasty in the pediatric patient.

BACKGROUND AND PURPOSE: Laparoscopic dismembered pyeloplasty is an acceptable option for ureteropelvic junction (UPS) obstruction in the pediatric population. We compared our results with dismembered and nondismembered laparoscopic pyeloplasty. PATIENTS AND METHODS: A series of 26 children between the ages of 8 months and 15 years (mean age 5 years) underwent transperitoneal laparoscopic pyeloplasty for an obstruction not caused by a crossing vessel. Nineteen had an Anderson-Hynes dismembered pyeloplasty (AH), while the remaining seven had a nondismembered pyeloplasty in a Heineke-Mikulicz fashion (HM). The outcome measures were operative time, length of hospital stay, and resolution of obstruction by ultrasonography and diuretic radionuclide imaging. RESULTS: The mean operative time was 3.1 hours and 2.5 hours for AH and HM, respectively. No difference in hospital stay was noted, with a mean of 3 days. The stent was removed 6 weeks later. Four of the seven patients having nondismembered procedures presented with acute flank pain within 3 days of stent removal. The AH pyeloplasty produced a 94% rate of resolution of UPJ obstruction, while the HM patients did poorly, with a success rate of only 43% (P = 0.002; Fisher's exact test). CONCLUSIONS: We believe that for UPJ obstructions in children not involving a crossing vessel, laparoscopic dismembered (AH) pyeloplasty may be considered a safe alternative.

Gross hematuria in a 3-year-old girl caused by a large isolated bladder hemangioma.

Hemangiomas of the urinary tract can arise anywhere along the system. Although rare, these lesions can result in significant hematuria, with potential for patient morbidity. We report a case of an isolated bladder hemangioma identified in a 3-year-old girl presenting with recurrent high-volume gross hematuria. The lesion was not amenable to endoscopic resection because of its size. We present our operative management strategy as a potential method for other urologists who may be presented with similar scenarios.

Iatrogenic ureteral injury after laparoscopic cholecystectomy in a 13-year-old boy.

We present a report of a delayed ureteral injury after a laparoscopic cholecystectomy. The patient presented with one episode of gross hematuria after surgery. He was treated with ureteral stent drainage and did well with no long-term sequelae.

Influence of type of conduit and site of implantation on the outcome of continent catheterizable channels.

OBJECTIVE: Continent catheterizable channels (CCC) using the Mitrofanoff principle are essential for pediatric urinary tract reconstruction. There is controversy over the influence of type of CCC (appendix vs. Yang-Monti) and site of implantation (augmentation vs. native bladder) on outcome. PATIENTS AND METHODS: A retrospective record review was conducted of all patients undergoing CCC since 1999, excluding patients who underwent seromuscular colocystoplasty. We analyzed the type of channel, site of implantation, complications requiring re-operation, and the revision rate according to type of CCC, type of stoma, site of implantation (bladder vs. augmentation) and segment used for augmentation (ileum vs. sigmoid colon). RESULTS: There were 41 patients with a mean age of 11.2 years and a mean follow-up of 33.3 months. Of these, 33 CCC were constructed with appendix and eight with a Yang-Monti technique (4 ileal, 4 sigmoid); 31 patients also had an enterocystoplasty (19 sigmoid, 9 ileal and 3 others). Overall revision rate was 27%; revision was required in 8/33 (24%) appendiceal and 3/8 (38%) Yang-Monti CCC (P=0.7). Revisions were required in 4/21 CCC implanted in the native bladder and 7/20 implanted in augmented bladder (P=0.3). The majority of revisions were at skin level. CONCLUSIONS: Although there was no statistical difference in revision rate according to type of CCC, type of stoma or site of implantation, complications appeared to be more common in patients requiring a more complex reconstruction.

Magnetic resonance imaging of renal abnormalities in patients with congenital osseous anomalies of the spine.

BACKGROUND: Patients with congenital osseous anomalies of the spine are known to have a high prevalence of abnormalities in the renal system and of the spinal cord. Today, the screening tools of choice to detect these abnormalities include ultrasonography of the kidneys and collecting system and magnetic resonance imaging of the spine. A single screening tool that can identify both renal and intraspinal anomalies would be ideal. METHODS: Imaging studies of all patients with a congenital osseous anomaly of the spine seen at our institution during a ten-year period were retrospectively reviewed. Only patients who had had both a sonogram of the renal system and a magnetic resonance imaging study of the entire spine were included in the investigation. All studies were reviewed blindly by a pediatric radiologist for this study. RESULTS: One hundred and fifty-three patients met the criteria for inclusion in the study. Forty-one patients (27%) had a total of forty-seven renal abnormalities noted on both the sonogram and the magnetic resonance imaging scan. In no instance was a renal anomaly seen on one study and not on the other. CONCLUSIONS: When properly performed, screening magnetic resonance imaging scans of the spine can show renal abnormalities, thus obviating the need for a separate screening renal ultrasound study.

Transperitoneal laparoscopic pyeloplasty for primary repair of ureteropelvic junction obstruction in infants and children: comparison with open surgery.

PURPOSE: Pediatric laparoscopic pyeloplasty to treat ureteropelvic junction obstruction has been reported to decrease hospitalization stay and the analgesic requirement compared to open pyeloplasty. It is not clear if all age groups benefit from this procedure. We compared primary laparoscopic and open pyeloplasty in infants and children. MATERIALS AND METHODS: We retrospectively reviewed the records of consecutive primary pyeloplasties at a single institution during a 4.5-year period. Demographic data, body measurements, presentation, indications for surgery, operation type, surgical time, complications, analgesia requirement, hospital stay and outcome were recorded. RESULTS: Patients were divided in the open pyeloplasty group of 41 and the laparoscopic pyeloplasty group of 37. The groups were similar with regard to sex and laterality. There were more patients 14 months or younger in the open pyeloplasty group. Mean surgical time was longer in laparoscopic pyeloplasty but it decreased significantly after the first 15 cases (each p <0.001). Hospitalization and postoperative analgesia requirements were similar in the 2 groups. There was a higher success rate for laparoscopic pyeloplasty in patients older than 14 months (p <0.05). In the open pyeloplasty group there were more re-interventions as well as a trend toward more complications and readmissions. CONCLUSIONS: Transperitoneal laparoscopic pyeloplasty was performed safely in all pediatric age groups with minimal morbidity and excellent short-term results. In our experience laparoscopic pyeloplasty in infants and children is more difficult and time-consuming surgery than open pyeloplasty. However, it may provide a better outcome with fewer complications and better cosmesis. Prospective studies are needed to confirm these results.

Comparison of laparoscopic and open partial nephrectomy for duplication anomalies in children.

PURPOSE: We compared the outcome of laparoscopic vs open PN for duplication anomalies at our institution. MATERIALS AND METHODS: We retrospectively reviewed the records of all patients undergoing PN within the last 4 years. RESULTS: A total of 34 patients (16 females) were divided into 2 groups. Group 1 consisted of 20 patients undergoing open PN between 2000 and 2003, and group 2 consisted of 14 patients undergoing laparoscopic PN between 2003 and 2004. Mean patient age was 21 months in group 1 and 18 months in group 2. Diagnosis was ectopic ureter in 18 patients, ureterocele in 11, VUR in 4 and ureteropelvic junction obstruction in 1. Cystoscopy was performed as part of the procedure in 30% of the patients in group 1 and 100% of those in group 2. Simultaneous lower tract procedures were performed in 3 patients in group 1 and 2 patients in group 2. Mean duration of PN was 115 minutes for group 1 and 180 minutes for group 2. There was no significant bleeding or need for transfusion except in 1 patient in the open group. Median hospitalization was 3 days for group 1 and 2 days for group 2. Mean analgesic requirement was 2.3 doses of opioids and 2 doses of ketorolac for group 1, and 3.2 doses of opioids for group 2. Acetaminophen only was used in 3 of 20 patients in group 1 and 5 of 14 in group 2. There were 2 complications in each group, namely 1 case of ureteral bleeding and 1 lower pole ureteral injury in group 1, and 1 omental hernia and 1 urinoma in group 2. CONCLUSIONS: Laparoscopic PN is feasible even in small infants, and the results are comparable to the open procedure. Length of hospitalization was shorter in the laparoscopic group. In our series the learning curve for this technique was rapid, and after a few cases the procedure could be done in the same time as open surgery, with the advantages offered by laparoscopy.