Baseline Clinical and Biomarker Characteristics of Biobank Innovations for Chronic Cerebrovascular Disease With Alzheimer’s Disease Study: BICWALZS

Objective@#We aimed to present the study design and baseline cross-sectional participant characteristics of biobank innovations for chronic cerebrovascular disease with Alzheimer’s disease study (BICWALZS) participants. @*Methods@#A total of 1,013 participants were enrolled in BICWALZS from October 2016 to December 2020. All participants underwent clinical assessments, basic blood tests, and standardized neuropsychological tests (n=1,013). We performed brain magnetic resonance imaging (MRI, n=817), brain amyloid positron emission tomography (PET, n=713), single nucleotide polymorphism microarray chip (K-Chip, n=949), locomotor activity assessment (actigraphy, n=200), and patient-derived dermal fibroblast sampling (n=175) on a subset of participants. @*Results@#The mean age was 72.8 years, and 658 (65.0%) were females. Based on clinical assessments, total of 168, 534, 211, 80, and 20 had subjective cognitive decline, mild cognitive impairment (MCI), Alzheimer’s dementia, vascular dementia, and other types of dementia or not otherwise specified, respectively. Based on neuroimaging biomarkers and cognition, 199, 159, 78, and 204 were cognitively normal (CN), Alzheimer’s disease (AD)-related cognitive impairment, vascular cognitive impairment, and not otherwise specified due to mixed pathology (NOS). Each group exhibited many differences in various clinical, neuropsychological, and neuroimaging results at baseline. Baseline characteristics of BICWALZS participants in the MCI, AD, and vascular dementia groups were generally acceptable and consistent with 26 worldwide dementia cohorts and another independent AD cohort in Korea. @*Conclusion@#The BICWALZS is a prospective and longitudinal study assessing various clinical and biomarker characteristics in older adults with cognitive complaints. Details of the recruitment process, methodology, and baseline assessment results are described in this paper.

A Prospective Comparative Study of Mobile Acoustic Uroflowmetry and Conventional Uroflowmetry / 대한배뇨장애요실금학회지

Purpose@#The aim of this study was to assess the performance of a mobile acoustic Uroflowmetry (UFM) application compared with standard UFM in the pediatric population. @*Methods@#A mobile acoustic UFM application represents a noninvasive method to estimate the urine flow rate by recording voiding sounds with a smartphone. Male pediatric patients who were undergoing UFM testing were prospectively recruited, and the voiding sounds were recorded and analyzed. The intraclass correlation coefficient (ICC) was used to compare the maximum flow rate (Qmax), average flow rate (Qavg), voiding time (VT), and voiding volume (VV) as estimated by acoustic UFM with those calculated by standard UFM. Differences in Qmax, Qavg, VT, and VV between the 2 UFM tests were determined using 95% Bland-Altman limits of agreement. @*Results@#A total of 16 male patients were evaluated. Their median age was 9 years. With standard UFM, the median Qmax, Qavg, VT, and VV were 18.7 mL/sec, 11.1 mL/sec, 15.2 seconds, and 157.8 mL, respectively. Strong correlations were observed between the 2 methods for Qmax (ICC=0.755, P=0.005), VT (ICC=0.974, P<0.001), and VV (ICC=0.930, P<0.001), but not for Qavg (ICC=0.442, P=0.135). The Bland-Altman plot showed good agreement between the 2 UFM tests. Flow patterns recorded by acoustic UFM and conventional UFM showed good visual correlations. @*Conclusions@#Acoustic UFM was comparable to standard UFM for male pediatric patients. Further validation of its performance in different toilet settings is necessary for broader use.

Prognostic Significance of Immunohistochemical MSH2 Expression in Prostate Cancer

PURPOSE: There are numerous prostate cancer-related genes that involve in carcinogenesis and tumor progression. Among the genes, DNA mismatch repair genes recognize and repair misincorporated nucleotides during DNA replication. In this analysis, we evaluated the association of hMSH2 which is one of the mismatch repair genes, with risk of aggressive prostate cancer and prostate cancer recurrence. MATERIALS AND METHODS: Immunohistochemistry was performed in 46 patients who diagnosed prostate cancer and underwent radical prostatectomy between January 2006 and December 2012 at Kyung Hee University Hospital at Gangdong. We evaluated an association between the degree of hMSH2 immunohistochemical staining and various clinical variables including prostate-specific antigen (PSA), Gleason score, pathological stage, and biochemical recurrence. The intensity of immunostaining for hMSH2 was divided into 2 groups: low expression group (immunostaining score < 2) and high expression group (immunostaining score ≥2). RESULTS: Although seminal vesicle invasion was marginally associated with the degree of hMSH2 immunohistochemical staining, PSA, Gleason score, lymph node metastasis, presence of lymphatic, perineural, vascular invasion, and extracapsular extension were not associated with the degree of hMSH2 immunohistochemical staining. Furthermore, the association of biochemical recurrence free survival with hMSH2 expression was not statistically significant. CONCLUSIONS: The hMSH2 expression was marginally associated with risk of aggressive prostate cancer such as seminal vesicle invasion. Further evaluation with a larger number of cases is needed to verify these results.

NBR1 and KIF14 Downstream of the Mammarian Target of Rapamycin Pathway Predict Recurrence in Nonmuscle Invasive Low Grade Urothelial Carcinoma of the Bladder

PURPOSE: The lack of identified mammalian target of rapamycin (mTOR) pathway downstream genes that overcome cross-talk in nonmuscle invasive low grade (LG)-urothelial carcinoma (UC) of the bladder is a clinical limitation in the use of mTOR inhibitor for the treatment of UC. MATERIALS AND METHODS: Presently, gene expression patterns, gene ontology, and gene clustering by dual (p70S6K and S6K) siRNAs or rapamycin in 253J and TR4 cell lines were investigated by microarray analysis. mTOR/S6K pathway downstream genes suppressed to siRNAs, and rapamycin up-regulated or rapamycin down-regulated genes were identified. The mTOR downstream genes examined using a tissue microarray of 90 nonmuscle invasive LG-UC patients to assess whether any of these genes predicted clinical outcomes. A knockout study evaluated the synergistic effect with rapamycin. RESULTS: In the microarray analysis, mTOR pathway downstream genes selected consisted of 4 rapamycin down-regulated (FOXM1, KIF14, MYBL2, and UHRF1), and 4 rapamycin up-regulated (GPR87, NBR1, VASH1, and PRIMA1). In the tissue microarray, FOXM1, KIF14, and NBR1 were more expressed at T1, and MYBL2, and PRIMA1 were more expressed in tumors exceeding 3 cm. In a multivariate Cox regression model, KIF14 and NBR1 were significant predictors of recurrence in nonmuscle invasive LG-UC of the bladder. In a NBR1 knock out model, rapamycin treatment synergistically inhibited cell viability and colony forming ability compared to rapamycin only. CONCLUSIONS: The results implicate KIF14 and NBR1 as mTOR/S6K pathway downstream genes that predict recurrence in nonmuscle invasive LG-UC of the bladder and demonstrate that NBR1 knockout overcomes rapamycin cross-talk.

Behavioral therapy for enuresis

Behavioral therapy refers to a broad range of treatment modalities that regulate the child's behavior to induce a therapeutic effect on nocturnal enuresis. Simple behavioral therapies include fluid restriction, lifting, waking, introducing reward systems, and bladder training. Simple behavioral therapy is significantly less effective than an enuresis alarm or desmopressin. If a child needs treatment, an enuresis alarm or desmopressin should not be delayed. Enuresis alarms are an effective form of treatment, although they require active involvement of the health care provider to reduce the likelihood of dropout and to motivate the child and parents.

Trends in Testicular Injury in Korea, 1986–2015

The objectives of this study were to investigate patients treated for scrotal trauma at our institute for the last three decades to describe our experience with an emphasis on the etiologies and ultrasonographic findings in these patients. We reviewed medical records of patients who underwent scrotal ultrasonography for evaluation of testicular trauma at our institutes from 1986 to 2015. Trends regarding the etiology of scrotal trauma were evaluated during each decade. The echo pattern and contour definition of the testicular parenchyma and the pattern of hematoma development were recorded to evaluate radiographic findings of testicular injury. The correlation between ultrasonographic and intraoperative findings was assessed. A total of 115 patients were analyzed. Most patients (92.2%) presented with blunt trauma. The most common etiology of testicular trauma was assault during the first and second decades, while injury related to a fall was most common during the third decade. Of the 77 patients (67.0%) who underwent urgent exploration, 46 patients (59.7%) had testicular rupture. Loss of contour definition, heterogeneous echo pattern of the testicular parenchyma, and testicular hematoma showed a moderate to strong degree of correlation with testicular rupture (Spearman correlation co-efficient: 0.5–0.8). Over the past 30 years, the etiology of testicular injury changed from assault to falls or athletic injury and the severity of injury has decreased. Our findings demonstrate the importance of ultrasonography for determining an appropriate management strategy in scrotal trauma. Surgical exploration should be considered in patients with abnormal ultrasonographic findings.

Obesity in Korean Men: Results from the Fourth through Sixth Korean National Health and Nutrition Examination Surveys (2007~2014)

PURPOSE: Obesity is related to many diseases, including urological conditions. We investigated the prevalence, risk factors, and treatment of male obesity. MATERIALS AND METHODS: This study included 17,485 men older than 20 years of age who participated in the fourth, fifth, and sixth administrations of the Korean National Health and Nutrition Examination Survey. Two main cutoff points for obesity were defined: a body mass index (BMI) ≥25 kg/m2 and a BMI≥30 kg/m2. Additionally, we defined obesity requiring pharmacotherapy as the presence of a BMI≥30 kg/m2 or a BMI≥27 kg/m2 co-occurring with at least one associated comorbid medical condition, such as hypertension, dyslipidemia, or diabetes. RESULTS: The prevalence rates of a BMI≥25 kg/m2, a BMI≥30 kg/m2, and obesity requiring pharmacotherapy were 35.7%, 3.4%, and 10.5%, respectively. The prevalence of obesity increased over time for all definitions of obesity. The prevalence of obesity requiring pharmacotherapy was highest in Jeju (12.5%) and lowest in Gangwon-do (7.7%). Having a higher income, being a non-manual worker, and having completed a high level of education were significantly related to obesity requiring pharmacotherapy. More than 70% of patients with obesity requiring pharmacotherapy reported taking diet pills, eating functional foods, or consuming a one-food diet for weight reduction, but only 13.9% reported exercising for this purpose. CONCLUSIONS: Male obesity is a common condition, the prevalence of which is expected to continue to increase over time. A better strategy is required to manage male obesity in Korea.

Risk Factor Analysis of Ciprofloxacin-Resistant and Extended Spectrum Beta-Lactamases Pathogen-Induced Acute Bacterial Prostatitis in Korea

The objectives of this study were to investigate risk factors and the incidence of ciprofloxacin resistance and extended-spectrum beta-lactamases (ESBL) in patients with acute bacterial prostatitis (ABP). We reviewed the medical records of 307 patients who were diagnosed with ABP between January 2006 and December 2015. The etiologic pathogens and risk factors for ciprofloxacin-resistant E. coli and ESBL-producing microbes, susceptibility to ciprofloxacin, and the incidence of ESBL in patients with ABP were described. History of prior urologic manipulation was an independent risk factor for ciprofloxacin-resistant (P = 0.005) and ESBL-producing microbes (P = 0.005). Advanced age (over 60 years) was an independent risk factor for ciprofloxacin-resistant microbes (P = 0.022). The ciprofloxacin susceptibility for Escherichia coli in groups without prior manipulation was documented 85.7%. For groups with prior manipulation, the susceptibility was 10.0%. Incidence of ESBL-producing microbes by pathogen was 3.8% for E. coli and 1.0% for Klebsiella pneumonia in the absence of manipulation group, and 20% and 33.3% in the presence of manipulation group, respectively. Initial treatment of ABP must consider patient's age and the possibility of prior manipulation to optimize patient treatment. With the high rate of resistance to fluoroquinolone, cephalosporins with amikacin, or carbapenems, or extended-spectrum penicillin with beta lactamase inhibitor should be considered as the preferred empirical ABP treatment in the patients with history of prior urologic manipulation.

Analysis of NF-κB and Clinical Prognostic Factors in Clear Cell Renal Cell Carcinoma

PURPOSE: A multi-subunit transcription factor NF-κB is associated with anti-apoptotic signals in several cancers including renal cell carcinoma (RCC). In this study, we investigated whether the expression levels of the NF-κB were related to the clinical properties of human renal cell carcinoma such as nuclear grade, TNM stage, and recurrence free survival. MATERIALS AND METHODS: Patients who were diagnosed with clear cell RCC between January 2006 and February 2013 were included. Clinicopathological data and survival were investigated. The expressions of NF-κB were investigated by performing immunohistochemical staining on 61 clear cell RCC. The expression levels of NF-κB were divided two groups by the expression levels. RESULTS: Results on the expression of NF-κB were not significant. Analysis of NF-κB expressions is not associated with any of the clinical properties including age, nuclear grade and TNM stage (p=0.613, p=0.059, p=0.107, p=0.570, and p=0.760, respectively). Also, a statistically correlation was not observed between recurrence free survival and NF-κB expression levels (p=0.573). CONCLUSIONS: The expressions of the NF-κB were not associated with the clinical properties of clear cell RCC such as age, nuclear grade, TNM stage, and recurrence free survival.

Choroidal Metastasis from Prostate Cancer

Metastasis of choroid from prostate cancer is not common and has not been reported before in Korea. We report a case of decreased vision in a patient with prostate cancer. After external beam radiotherapy, patient had complete response in the choroidal metastasis. Metastasis of choroid secondary to prostate is not common. There have been only 8 cases reported. In this case, we demonstrated that external beam radiotherapy showed a therapeutic effect.

Incidence of Nitrituria and Its Association With Metabolic Syndrome: Results From the Korean National Health and Nutrition Examination Survey V (2010-2012) / 대한배뇨장애요실금학회지

PURPOSE: To investigate the incidence of nitrituria and the relationship between nitrituria and metabolic syndrome (MetS). METHODS: Data from the Korean National Health and Nutrition Examination Survey V were used. A total of 19,083 participants were included. The chi-square test, the Mantel-Haenszel extension, logistic regression analysis, and multiple linear regression were used to analyze the data. RESULTS: A total of 2.0% of the participants had nitrituria. The incidence of nitrituria significantly increased with age (P trend<0.001). In addition, nitrituria in women began to significantly increase in the fifth decade, more than in men, and this difference was maintained in the 60s, 70s, and greater than 70s age groups (P<0.001). After adjusting for confounders, the odds ratio (OR) for nitrituria in the MetS group was significantly increased, as compared to the OR for nitrituria in the group without MetS (MetS: OR, 1.577; 95% confidence interval [CI], 1.134-2.192; P=0.007). The glycosylated hemoglobin of the nitrite positive group was significantly higher than the negative group (adjusted mean ±standard error: 6.108 ±0.081 vs. 5.883±0.065, P<0.001). CONCLUSIONS: An effective health policy for urinary tract infection (UTI) is needed for older age groups and women. Screening or management guidelines for UTI are needed in MetS patients.

Analysis of factors affecting spontaneous expulsion of ureteral stones that may predict unfavorable outcomes during watchful waiting periods: What is the influence of diabetes mellitus on the ureter?

PURPOSE: The aim of our study was to evaluate the association of several factors with spontaneous stone expulsion, including ureteral stone characteristics (size, location, hydronephrosis, perinephric stranding), types of medications prescribed (alpha-blocker, low-dose steroid), and other possible demographic and health-history factors (gender, age, serum creatinine, underlying diabetes mellitus [DM], and hypertension). MATERIALS AND METHODS: A total of 366 patients with ureteral stones were enrolled. All patients underwent watchful waiting without any invasive procedures. Initial diagnoses of ureteral stones were confirmed by computed tomography scans, which were taken at approximately 1-month intervals to check for stone expulsion. Univariate and multivariate analyses were conducted to identify significant factors that contributed to stone expulsion. RESULTS: Among 366 patients, 335 patients (91.5%) experienced spontaneous stone passage during a mean follow-up period of 2.95+/-2.62 weeks. The patients were divided into two groups depending on the success of spontaneous stone passage. Univariate analyses revealed that stone location (p=0.003), stone size (p=0.021), and underlying DM (p<0.001) were significant predictors of stone passage. Multivariate analyses confirmed that stone size (p=0.010), stone location (p=0.008), and underlying DM (p=0.003) were independent predictive factors affecting stone passage. CONCLUSIONS: Stone size, location, and underlying DM were confirmed to be significant predictive factors for spontaneous passage of ureteral stones. Urologists should consider active procedures, such as shock wave lithotripsy or ureteroscopy, rather than conservative management in patients presenting with proximally located stones, large ureteral stones, or underlying DM.

Establishment of Reference Ranges for Prostate Volume and Annual Prostate Volume Change Rate in Korean Adult Men: Analyses of a Nationwide Screening Population

We aimed to determine normal reference ranges for prostate volume (PV) and annual PV change rate in a Korean nationwide screening population. Data from men who underwent a routine health check-up were collected from 13 university hospitals. The cohort comprised men aged > or =40 yr who had undergone 2 or more serial transrectal ultrasonographies. Men with initial PV>100 mL; serum PSA level>10 ng/mL; PV reduction>20% compared with initial PV, or who had history of prostate cancer or prostate surgery, were excluded. Linear regression and mixed effects regression analyses were used to predict mean PV and longitudinal change in PV over time. A total of 2,967 men formed the study cohort. Age, body mass index (BMI), and serum prostate-specific antigen (PSA) level were found to be significant predictors of PV. A predicted PV table, with a 95% confidence interval (CIs), was developed after adjusting for these 3 variables. Annual PV change rate was 0.51 mL/year (95% CI, 0.47-0.55). Annual PV change rate according to age was 0.68 mL/year, 0.84 mL/year, 1.09 mL/year, and 0.50 mL/year for subjects in their 40s, 50s, 60s, and > or =70 yr, respectively. Predicted annual PV change rate differed depending on age, BMI, serum PSA level and baseline PV. From a nationwide screening database, we established age-, PSA-, and BMI-specific reference ranges for PV and annual PV change rate in Korean men. Our newly established reference ranges for PV and annual PV change rate will be valuable in interpreting PV data in Korean men.

A Nationwide Epidemiological Study of Testicular Torsion in Korea

Testicular torsion is a surgical emergency in the field of urology. Knowledge of the epidemiology and pathophysiology is significant to an urologist. However, the epidemiology of testicular torsion in Korea has not been studied. We performed a nationwide epidemiological study to improve knowledge of the epidemiology of testicular torsion. From 2006-2011, the Korean Urologic Association began the patient registry service. The annual number of patients with testicular torsion from 2006 to 2011 were 225, 250, 271, 277, 345, and 210, respectively. The overall incidence of testicular torsion in males was 1.1 per 100,000; However, the incidence in men less than 25 yr old was 2.9 per 100,000. Adolescents showed the highest incidence. Total testicular salvage rate was 75.7% in this survey. There was no geographic difference of testicular salvage rate. Minimizing the possibility of orchiectomy for testicular torsion is important to improve public awareness to expedite presentation and provider education to improve diagnosis and surgery.

Urothelial Tumors of the Urinary Bladder in Two Adolescent Patients: Emphasis on Follow-up Methods

Here we describe two cases of papillary urothelial neoplasm of low malignant potential in adolescent boys. One case was a 16-year-old boy with a polypoid mass beside the right ureteral orifice and the other case was a 13-year-old boy with a papillary mass beside the left ureteral orifice. The initial presentation was hematuria in both cases and the bladder mass was detected by ultrasonography. Complete resection of the bladder tumor was performed by using an 11-Fr pediatric resectoscope. Follow-up has been performed with urine analysis, urine cytology, and bladder ultrasonography or cystoscopy every 3 months with no evidence of recurrence.

Predictive Value of Preoperative Unenhanced Computed Tomography During Ureteroscopic Lithotripsy: A Single Institute's Experience

PURPOSE: Ureteroscopic stone removal is frequently used to remove ureteral stones. Mucosal edema and bleeding are the two most important obstacles to a successful operation. This study analyzed relationships between unenhanced computed tomography (UECT) findings and ureteroscopic findings to determine whether ureteroscopic results could be predicted preoperatively by using UECT imaging. MATERIALS AND METHODS: From January 2009 to July 2011, 675 patients were diagnosed with ureteral stones through UECT. Among them, we retrospectively reviewed 92 cases of patients who underwent ureteroscopy (URS). We identified findings such as hydronephrosis, rim sign, periureteral fat stranding, and perinephric fat stranding on the UECT and then categorized these findings into four categories (none, mild, moderate, and severe) according to their severity. We also divided the URS findings of mucosal edema and bleeding into four categories (none, mild, moderate, and severe) and compared these findings with the UECT images. RESULTS: A total of 92 study patients were included in this study: 59 were male and 33 were female patients. According to the location of the stone, 31 cases were classified as upper ureteral stones, 15 were midureteral stones, and 46 were lower ureteral stones. Hydronephrosis identified with UECT was correlated with the mucosal edema severity observed during URS (p=0.004). The rim signs identified with UECT were proportional to the grade of mucosal edema (p=0.010). CONCLUSIONS: Hydronephrosis and rim signs observed during UECT can be used as a predictive factor for intraoperative mucosal edema in patients undergoing URS.

Efficacy and Safety of Propiverine in Children with Overactive Bladder

PURPOSE: Antimuscarinic therapy remains one of the most common forms of therapy for overactive bladder (OAB) in children. However, few clinical studies on the outcomes of antimuscarinics in children with OAB have been published. Therefore, we evaluated the efficacy and safety of propiverine, which is frequently prescribed for the treatment of pediatric OAB. MATERIALS AND METHODS: We retrospectively reviewed children with OAB treated with propiverine within the past 5 years. The response rates were compared between the non-urge incontinence (non-UI) and urge incontinence (UI groups). The cumulative response rate by treatment duration was also compared between the two groups. RESULTS: Among a total of 68 children, 50 children (73.5%) experienced UI. The overall response rate was 86.8%. Functional bladder capacity after treatment was 150 ml, which represented an increase compared with the value (140 ml) before treatment. The voiding frequency per day decreased from 14.0 to 8.5 times. The overall response rate (88.0%) in the non-UI group was not significantly different from that seen in the UI group (83.3%; p>0.05). In non-UI children, the cumulative response rates were 36.0%, 54.0%, 68.0%, 74.0%, 76.0%, and 78.0% at 4, 8, 12, 16, 20, and 24 weeks, respectively. The cumulative response rates in the UI children were 11.1%, 33.3%, 44.4%, 50.0%, 50.0%, and 55.6%, respectively during the same respective time periods. Adverse effects were identified in only two (2.9%) patients, and neither case was severe. CONCLUSIONS: Propiverine is effective and well tolerated as a treatment for children suffering from OAB with or without UI.

Bypass Using Autologous Pericardium in the Inflammatory Pseudotumor of the Superior Vena Cava

Among the causes of superior vena cava (SVC) syndrome, intraluminal tumor, especially the inflammatory pseudotumor is very rare. We report a 33-year old male patient who had been suffering from facial edema and flushing for 3 weeks before admission. On physical examination, facial edema and venous engorgement on upper extremities and upper chest wall were showed. The chest computed tomography (CT) scan showed a long intraluminal mass lesion resulting in a near total obstruction of the SVC. Surgery was performed through median sternotomy. After complete resection of the tumor, we make bypass of SVC with autologous pericardium. The follow up chest CT scan revealed no abnormality 3 months after the operation.

Sudden Pulseless Ventricular Tacchycardia during the Emergence of a Child after the General Anesthesia, and Suspected Viral Myocarditis

A 10-year-old female child was underwent the tonsillectomy and adenoidectomy. She was relieved from the upper respiratory tract infection about 1 week before the operation. Her heart rate was recorded 100 to 110 per minute at the preanesthetic period, and then increased to about 140 per minute during the operation. We speculated that tacchycardia resulted from the inhalation anesthesia of sevoflurane as other common cases, so we didn't consider it as a serious problem. But the taccycardia was not relieved after the termination of anesthesia, and after the extubation, it was severely and rapidly aggravated to the ventricular tacchycardia with the circulatory collapse during the emergence period. After the rapid defibrillation and the chest compression, her resuscitation was successfully finished. We suspected her event was derived from the childhood cardiomyopathy, especially the viral myocarditis. So we reviewed viral myocarditis and focused a new aspect of childhood cardiac disease and screening.

Laparoendoscopic Single-Site Pyeloplasty Using Additional 2 mm Instruments: A Comparison with Conventional Laparoscopic Pyeloplasty

PURPOSE: Despite a recent surge in the performance of laparoendoscopic single-site surgery (LESS), concerns remain about performing LESS pyeloplasty (LESS-P) because of the technical difficulty in suturing. We report our techniques and initial experiences with LESS-P using additional needlescopic instruments and compare the results with conventional laparoscopic pyeloplasty (CL-P). MATERIALS AND METHODS: Nine patients undergoing LESS-P were matched 2:1 with regard to age and side of surgery to a previous cohort of 18 patients who underwent CL-P. In both groups, the operating procedures were performed equally except for the number of access points. In the LESS-P group, we made a single 2 cm incision at the umbilicus and used a homemade port. We also used additional 2 mm needlescopic instruments at the subcostal area to facilitate suturing and the ureteral stenting. RESULTS: The preoperative characteristics were comparable in both groups. Postoperatively, no significant differences were noted between the LESS-P and CL-P cases in regard to length of stay, estimated blood loss, analgesics required, and complications. But, LESS-P was associated with a shorter operative time (252.2 vs. 309.7 minutes, p=0.044) and less pain on postoperative day one (numeric rating scale 3.7 vs. 5.6, p=0.024). The success rate was 94% with CL-P (median, 23 months) and 100% with LESS-P (median, 14 months). CONCLUSIONS: Our initial experiences suggest that LESS-P is a feasible and safe procedure. The use of additional 2 mm instruments can help to overcome the difficulties associated with LESS surgery.