Validation of acoustic voided volume measure: a pilot prospective study.

PURPOSE: We evaluated the accuracy and reliability of a new smartphone-based acoustic voided volume (VV) measurement application compared to VV estimation based on the measurement of urine volume in a bladder by ultrasound bladder scan. PATIENTS AND METHODS: A total of 53 subjects from 01/2021 to 09/2021 were prospectively enrolled. Bladder scan-based VV estimation is based on the difference in the volume of urine in a bladder measured before urination and volume measured after urination. The acoustic VV measurement is based on smartphone-based acoustic VV measurement mobile application. VV estimates for the same void were compared between two techniques. Urinary measures were obtained from 49 male subjects resulting in a total of 245 measurements for analysis. VV measures were compared using Pearson's correlation coefficient (PCC), evaluation of observed versus predicted VV measures using linear regression fit indices, and Bland-Altman method. RESULTS: VV between the two techniques revealed strong correlation (PCC 0.811, p < 0.001). Means of the number of measurements per patient and inpatient days for measurements analyzed are 5 and 2.7, respectively. In 245 measurements, VV measured by bladder scan is 238.69 ± 122.32 mL, VV measured by mobile application is 254.69 ± 119.28 mL, and their difference of two measurements is 16 ± 74.29 mL. CONCLUSION: Through the comparison with VV estimated by ultrasound bladder scan, which is a technology to measure the urine volume in a bladder, it was confirmed that the smartphone-based acoustic VV measurement application proudP® is accurate.

The association between prostatitis and risk of prostate cancer: a National Health Insurance Database study.

PURPOSE: Inflammation is thought to affect the development of prostate cancer (PCa). By retrospectively investigating the database of the National Health Insurance Service, this study attempted to perform a relevant analysis of patients with prostatitis and PCa. METHODS: Participants were aged ≥ 50 years. Patients diagnosed with prostatitis between 2010 and 2013 and matched controls were followed up until 2019. We selected controls with matched propensity scores for age, diabetes, hypertension, and the Charlson comorbidity index. Multivariate Cox regression analysis was conducted to determine the hazard ratio (HR) and 95% confidence interval (CI) of the association between prostatitis and PCa. The HR for PCa according to the presence of prostatitis was classified as acute, chronic, or other prostatitis. RESULTS: A total of 746,176 patients from each group were analyzed. The incidence of PCa was significantly higher in the group with prostatitis (1.8% vs 0.6%, p < 0.001). The HR for PCa was significantly higher in patients with prostatitis (HR 2.99; 95% CI 2.89-3.09, p < 0.001). The HR for PCa was significantly higher in acute prostatitis than in chronic prostatitis (3.82; 95% CI 3.58-4.08; p < 0.001; HR 2.77; 95% CI 2.67-2.87, p < 0.001). The incidence of all-cause death in patients diagnosed PCa was significantly lower in prostatitis group (HR 0.58, 95% CI 0.53-0.63, p < 0.001). CONCLUSION: Prostatitis is associated with an increased incidence of PCa. Acute prostatitis is associated with higher risk of PCa than chronic prostatitis. Clinicians should inform patients with prostatitis that they may have an increased risk of diagnosing PCa, and follow-up is needed.

Pattern Analysis of Laser Fiber Degradation According to the Laser Setting: In Vitro Study of the Double-Firing Phenomenon.

BACKGROUND: It is essential to understand the mechanism of the various causes of laser fiber damage and an ideal method of reducing endoscope damage induced by laser emission in multiple sites. This study classified the different patterns of laser fiber degradation according to laser settings and analyzed the role of cavitation bubbles to find a desirable way of minimizing endoscope damage. METHODS: A total of 118 laser fibers were analyzed after 1-,3-, and 5-min laser emission to artificial stones under the settings of 1 J-10 Hz, 1 J-20 Hz, 1 J-30 Hz, and 2 J-10 Hz. Every 3 cm from the fiber tip was marked and examined with a digital microscope and a high-speed camera. The images of the fibers and the movement of cavitation bubbles were taken with a distance of 1 to 5 mm from the gel. RESULTS: Seven types of fiber damage (charring, limited and extensive peeled-off, bumpy, whitish plaque, crack, and break-off) coincided during laser emission. Damages rapidly increased with emission time > 3 minutes regardless of the laser settings. The damaged lengths covered 5 mm on average, and the fibers at 5-min emission were significantly shorter than others. The fiber durability of 1J-10Hz setting was better than other settings after 3-min laser emission. Backward movement of the cavitation bubbles was found at the 1-mm distance from the gel, and the damaged lengths were longer than the diameters of the cavitation bubbles because of their proximal movement. CONCLUSION: The damage patterns of the laser fiber tips were classified into seven types. The heat damage around the surface of the laser fiber can be increased according to the high-energy or high-frequency laser setting, a short distance to the stone, a short distance from the tips of flexible ureteroscopes, no cutting laser fiber procedures, and the inappropriate use of irrigation fluid or laser fiber jacket.

Prognosis after radical prostatectomy in men older than 75 years: long-term results from a single tertiary center.

Background: Despite longer lifespans, guidelines for prostate cancer treatment recommend surgery for those with over 10 years of life expectancy, potentially leaving older patients undertreated. This study examines the outcomes of radical prostatectomy (RP) in a large cohort of men older than 75 years. Materials and methods: We retrospectively analyzed 636 patients from a pool of 4,500 RP cases at a single tertiary institution from 2004 to 2022. Patients younger than 75 years or with incomplete records were excluded. Baseline clinical variables, including PSA and biopsy grade group (GG), as well as postoperative pathology and oncological outcomes, were assessed. Achievement of continence based on no pads and ≤1 pad at last follow-up were evaluated. Results: Mean age and PSA were 76.4 years and 15.3 ng/ml, respectively. At biopsy, GG1 and 2 were found in 18.1% and 31.5%, respectively, with 28.5% harboring GG4-5 tumors. After RP, 41.5% had GG upgrade compared to biopsy results, with 46.5% with ≥pT3 tumors. In a mean follow-up of 41.5 months, 82.3% were able to attain total continence of 0 pads, and 89.5% used ≤1 pads at the last follow-up. Overall and cancer-specific mortality was observed in 4.3% and 0.9%, respectively, and biochemical recurrence (BCR) occurred in 20.3% after a median of 154 months. At multivariate analysis, age was not a significant factor for BCR, whereas preoperative PSA, biopsy GG, margin positivity, and lymph node invasion were significant. Conclusion: RP is feasible in men older than 75 years with decent oncological outcome, with absolute age insignificant within this age group. Risk of undertreatment should be acknowledged, and definite treatment must be considered.

Validation of an algorithm for sound-based voided volume estimation.

A voiding diary is commonly used in clinical practice to monitor urinary tract health. However, manual recording and use of a measuring cup can cause significant inaccuracy and inconvenience. Recently sound-based voided volume estimation algorithms such as proudP have shown potential to accurately measure the voided volumes of patients urination while overcoming these inconveniences. In order to validate the sound-based voided volume estimation algorithm, we chose bodyweight change after urination as a reference value. Total 508 subjects from the United States and Korea were enrolled. 584 data points that have matching bodyweights change data and urination sound data were collected, and fivefold cross validation was performed in order to evaluate the model on all data in the dataset. The mean voided volume estimated by the algorithm was 202.6 mL (SD: ± 114.8) while the mean bodyweight change after urination was 208.0 g (SD: ± 121.5), and there was a strong linear correlation with high statistical significance (Pearson's correlation coefficient = 0.92, p-value < 0.001). Two paired t-test showed the equivalence with bodyweight change data with 10 mL margin. Additionally, a Bland-Altman plot shows a mean difference of - 5.5 mL with LoA (- 98.0, 87.1). The results support high performance of the algorithm across the large population data from multi-site clinical trials.

Comparative analysis of mortality and progression to end-stage renal disease between surgically induced and medical chronic kidney disease: A study using the National Health Insurance customized database.

PURPOSE: We aimed to compare the mortality rate and the risk for progression to end-stage renal disease (ESRD) and cardiovascular disease (CVD) between patients who underwent surgery for localized renal cell carcinoma (RCC) and those with chronic kidney disease (CKD) without surgery by investigating the National Health Insurance Service. MATERIALS AND METHODS: The surgical group (CKD-S) included patients who underwent radical or partial nephrectomy for RCC from 2007 to 2009. Grades of surgical CKD were classified according to the estimated glomerular filtration rate (eGFR) measured at a health screening within 2 years after surgery. The nonsurgical group (CKD-M) was graded according to the eGFR in the 2009-2010 health screenings. We performed 1:5 propensity score matching for age, gender, diabetes, hypertension, Charlson comorbidity index, smoking, alcohol consumption, baseline eGFR, and body mass index. RESULTS: A total of 8,698 patients (CKD-S, n=1,521; CKD-M, n=7,177) were analyzed. The CKD-M group was at higher risk for progression to ESRD (hazard ratio [HR] 1.90, 95% confidence interval [CI] 1.04-3.44, p=0.036) and CVD (HR 1.17, 95% CI 1.06-1.29, p=0.002) than the CKD-S group. In the group of patients with grade 3 disease or higher, the CKD-M group was at significantly higher risk for progression to ESRD (HR 2.21, 95% CI 1.47-3.31, p<0.001), CVD (HR 1.32, 95% CI 1.20-1.45, p<0.001), and overall mortality (HR 1.50, 95% CI 1.21-1.86, p<0.001). CONCLUSIONS: The risk for progression to ESRD, CVD, or mortality in patients with CKD-S may be lower than in patients with CKD-M.

A Newly Developed Hematuria Grading System May Predict the Status of Stone-Free and Acute Pyelonephritis of Minimally Invasive Renal Stone Surgery.

OBJECTIVES: The aim of this study was to evaluate the level of hematuria and the presence of clots during retrograde intrarenal surgery (RIRS) and miniaturized percutaneous nephrolithotomy (mPCNL) to predict surgical outcomes. MATERIALS AND METHODS: The data of patients who underwent RIRS and mPCNL were analyzed separately. A hematuria grading (HG) system was classified into five grades based on the presence of blood clots and any visible stones according to the irrigation settings. Inter-observer reliability of the grading system was assessed using intra-class correlation and Spearman's rho. RESULTS: The HG system showed high agreement among examiners, with high intra-class reliability and a strong correlation between RIRS and mPCNL groups. The stone density of the Houns-field unit was the most important factor in determining the hematuria across the development and validation groups of RIRS and mPCNL patients. Multivariate logistic regression analysis showed that the HG system was a significant predictor for remnant stones in the PCNL group and the probability of acute pyelonephritis or sepsis in the RIRS group. The high hematuria group showed lower basketing difficulty with the basket with a blue marker instrument than with others. CONCLUSIONS: The new HG system shows excellent inter-observer reliability and a correlation with a gradual increase in stone density and surgical difficulty.

Partial gland ablation using high-intensity focused ultrasound versus robot-assisted radical prostatectomy: a propensity score-matched study.

Background: We compared the clinical outcomes of robot-assisted radical prostatectomy (RARP) and partial gland ablation (PGA) using high-intensity focused ultrasound (HIFU) in localized prostate cancer. Methods: We analyzed 3,859 patients who had undergone RARP and PGA using HIFU. According to the propensity score for each treatment, 137 patients after PGA were matched to 3,722 patients after RARP at a 1:4 ratio using the nearest neighbor method. Results: The matched cohort comprised 685 subjects (RARP, 548; PGA, 137), with a median follow-up period of 22 months. Treatment failures were identified in 13.9% and 9.1% of patients in the PGA and RARP groups, respectively, after a median follow-up of 36 months postoperatively. Kaplan-Meier analyses revealed significantly longer failure-free (P < 0.001) and salvage-free survival (P = 0.003) in the RARP group than in the PGA group. There was no significant difference in the postoperative urinary symptom score (P = 0.748), but the postoperative erectile function score was significantly higher in the PGA group (P < 0.001). The rate of urinary incontinence (any pad) was significantly lower in the PGA group than that in the RARP group (P < 0.001). Postoperative complications were more frequent in the PGA group (P = 0.003); however, there was no significant difference in high-grade complications (≥3) (P = 0.467). Conclusion: PGA using HIFU showed statistically inferior oncological outcomes compared with RARP for failure-free survival and salvage-free survival. However, functional outcomes regarding postoperative incontinence and erectile dysfunction were more favorable in the PGA group.

Establishment of Prospective Registry of Active Surveillance for Prostate Cancer: The Korean Urological Oncology Society Database.

PURPOSE: To establish a prospective registry for the active surveillance (AS) of prostate cancer (PC) using the Korean Urological Oncology Society (KUOS) database and to present interim analysis. MATERIALS AND METHODS: The KUOS registry of AS for PC (KUOS-AS-PC) was organized in May 2019 and comprises multiple institutions nationwide. The eligibility criteria were as follows: patients with (1) pathologically proven PC; (2) pre-biopsy prostate-specific antigen (PSA) ≤20 ng/mL; (3) International Society of Urological Pathology (ISUP) grade 1 or 2 (no cribriform pattern 4); (4) clinical T stage ≤T2c; (5) positive core ratio ≤50%; and (6) maximal cancer involvement in the core ≤50%. Detailed longitudinal clinical information, including multi-parametric magnetic resonance imaging and disease-specific outcomes, was recorded. RESULTS: From May 2019 to June 2021, 296 patients were enrolled, and 284 were analyzed. The mean±standard deviation (SD) age at enrollment was 68.7±8.2 years. The median follow-up period was 11.2 months (5.9-16.8 mo). Majority of patients had pre-biopsy PSA ≤10 ng/mL (91.2%), PSA density <0.2 ng/mL² (79.7%), ISUP grade group 1 (94.4%), single positive core (65.7%), maximal cancer involvement in the core ≤20% (78.1%), and clinical T stage of T1c or lower (72.9%). Fifty-two (18.3%) discontinued AS for various reasons. Interventions included radical prostatectomy (80.8%), transurethral prostatectomy (5.8%), primary androgen deprivation therapy (5.8%), radiation (5.8%), and focal therapy (1.9%). The mean±SD time to intervention was 8.9±5.2 months. The reasons for discontinuation included pathologic reclassification (59.6%), patient preference (25.0%), and radiologic reclassification (9.6%). Two (4.8%) patients with pathologic Gleason score upgraded to ISUP grade group 4, no biochemical recurrence. CONCLUSIONS: The KUOS established a successful prospective database of PC patients undergoing AS in Korea, named the KUOS-AS-PC registry.

Optimal management of renal cell carcinoma in octogenarians: Retrospective analysis using updated Korean Renal Cell Carcinoma (KORCC) database.

BACKGROUND: There is few of optimal management guideline in elderly patients with renal cell carcinoma (RCC). To compare the survival outcomes of octogenarian RCC group and younger RCC group after surgery using nationwide multi-institutional database. METHODS: A total of 10,068 patients who underwent surgery for RCC were included in the current retrospective, multi-institutional study. A propensity score matching (PSM) analysis was conducted to control other confounding factors in analyzing survival outcomes of octogenarian and younger group RCCs. Kaplan-Meier curve analysis to calculate the survival estimates for cancer-specific survival (CSS) and overall survival (OS), and multivariate Cox-proportional hazard regression analyses to evaluate the significant variables associated with the survival outcomes were also performed. RESULTS: Both groups were well-balanced in all baseline characteristics. In a total cohort, Kaplan-Meier survival analysis showed a significantly decreased 5-year and 8-year CSS and OS in the octogenarian group compared with the younger group. However, in a PSM cohort, no significant differences were evident between the two groups in terms of CSS (5-year, 87.3% vs. 87.0%; 8-year, 82.2% vs. 78.9%, respectively, log-rank test, p = 0.964). In addition, age ≥ 80 years (HR, 1.199; 95% CI, 0.497-2.896, p = 0.686) was not a significant prognostic factor of CSS in a PSM cohort. CONCLUSIONS: The octogenarian RCC group after surgery had comparable survival outcomes compared with younger group after PSM analysis. For the life expectancy of octogenarian is getting longer, active treatment is considerable in patients with good performance status.

Surgical Parameters Related to Excessive Intrarenal Pressure during Minimally Invasive Percutaneous Nephrolithotomy in the Supine Position: A Prospective Observational Clinical Study.

Objective: Excessive intrarenal pressure (IRP) during surgery for renal stones is related to postoperative complications due to systemic absorption of bacteria and endotoxins. This study is aimed at evaluating factors that induce excessive IRP in minimally invasive percutaneous lithotripsy (mini-PCNL) in the supine position. Methods: 27 patients underwent mini-PCNL for intrarenal stones under supine position and were analyzed in this study. The IRP changes were measured at the phases of "baseline," "table tilting," "upper-pole navigation," "stone fragmentation," and "vacuum cleaning effect." The relationship between the mean IRP and cumulative time of IRP ≥ 30 cmH2O was analyzed by according to the surgical parameters. Multiple regression analysis showed the effect of the surgical parameters on postoperative fever-related IRP elevation. Results: Mean age was 59.3 ± 14.6 years. The mean stone burden was 24.6 ± 8.1 mm3. IRP was higher than baseline (31.6 ± 12.1) during upper-pole navigation (60.0 ± 22.9, p = 0.003) and stone fragmentation (46.2 ± 9.9, p < 0.001). The subgroup's IRP baseline < 20 cmH2O significantly increased during the upper-pole navigation. Changes in IRP at each stage were affected by baseline IRP (p < 0.001), operation methods (p = 0.021), number of calyces with stones (p = 0.034), and laser energy of Joules (p = 0.041) and frequency (p = 0.038). Conclusion: In supine mini-PCNL, the IRP was higher during laser fragmentation and upper-pole navigation. The table tilting procedure can be helpful in selected patients. The vacuum cleaner effect did not affect IRP.

Effectiveness of a newly-developed training module using 3D printing for the navigation during retrograde intrarenal surgery.

PURPOSE: This study aimed to evaluate the feasibility of the newly-developed three-dimensional (3D) printed training module for navigation during retrograde intrarenal surgery. MATERIALS AND METHODS: Two specialists provided orientation to all trainees. The 3D printing model consisted of eight calyces in each kidney. One navigation time started from the moment when the endoscope entered the ureter. After navigation was completed, the navigation time was recorded. The goal was to perform ten navigation times for each side, starting from the right or the left side at random. After the experiment, all trainees were asked to fill out a questionnaire. RESULTS: The average training period of all 17 trainees was 3.05±1.80 years. Eleven trainees (64.7%) had the experience of assisting surgery for <100 cases, and six trainees (35.3%) had the experience of assisting surgery for 100 to 500 cases. Nine trainees (52.9%) began training from the right, and eight trainees (47.1%) started from the left. The average navigation time of 308 trials was 153.4±92.6 seconds. The maximum and minimum navigation times were 354.3±177.2 seconds and 80.1±25.6 seconds. The mean navigation time of the first and the last trials of all trainees significantly decreased from 251.4±108.0 seconds to 93.9±33.2 seconds. The average reduction in navigation time was 201.3±133.3 seconds. Almost all trainees were satisfied with the training. CONCLUSIONS: The newly-developed 3D printing navigation training module seems to be adequate to improve surgical skills of flexible ureteroscopy.

Possibilities and limitations of using low biomass samples for urologic disease and microbiome research.

With the dogma of sterile urine no longer held as truth, numerous studies have implicated distinct changes in microbial diversity and composition to diseased subgroups in both benign and malignant urological diseases, ranging from overactive bladder to bladder and prostate cancer. Further facilitated by novel and effective techniques of urine culture and sequencing, analysis of the genitourinary microbiome holds high potential to identify biomarkers for disease and prognosis. However, the low biomass of samples included in microbiome studies of the urinary tract challenge researchers to draw definitive conclusions, confounded by technical and procedural considerations that must be addressed. Lack of samples and adequate true negative controls can lead to overestimation of microbial influence with clinical relevance. As such, results from currently available studies and assessment of their limitations required a thorough understanding. The purpose of this narrative review was to summarize notable microbiome studies in the field of urology with a focus on significant findings and limitations of study design. Methodological considerations in future research are also discussed.

Association between Psychological Suffering and Suicidal Thinking in Patients with Urologic Cancer Using Real-World Data.

Cancer is a leading cause of death in Korea, and depression and suicide are major psychiatric problems in cancer patients. This study aimed to explore the correlation between anxiety, depression, social support, cancer state, and suicidality among urologic cancer patients. Sixty patients with urologic cancer were admitted to a university hospital between October 2019 and February 2020. The patients were evaluated using the Patient Health Questionnaire-9, Generalized Anxiety Disorder 7-item scale, Suicidality module of the Mini International Neuropsychiatric Interview (MINI), and the Lubben Social Network scales (LSNS). To determine which psychological or demographic factors affected suicide risk, Fisher's exact test, Wilcoxon rank-sum test, regression, and logistic regression were conducted. It was found that the greater the depressive symptoms, the higher the suicidal risk (OR = 1.32, 95% CI = 1.08-1.61). Furthermore, anxiety symptoms and the duration of cancer after diagnosis significantly increased depressive symptoms (p = 0.032). Clinicians should be able to identify the risk factors for suicide in patients with cancer, one of which is depression. To assess the risk of suicide, we must evaluate not only depressive symptoms but also the related anxiety and duration of the disease. Prevention and intervention efforts are needed to improve depressive moods and anxiety after cancer diagnosis.

Geriatric assessment using the G8 to predict postoperative complications in patients undergoing major uro-oncologic surgery: Comparison with the Charlson Comorbidity Index.

OBJECTIVE: To evaluate the ability of the G8 assessment to predict postoperative complications in older adults undergoing major uro-oncologic surgery in comparison with the Charlson Comorbidity Index (CCI). MATERIALS AND METHODS: The study included patients ≥65 years old who underwent major uro-oncologic surgery between December 2017 and December 2019 and were enrolled in the Seoul National University Prospectively Enrolled Registry for Genitourinary Cancer (SUPER-GUC). Odds ratio (OR) smoothing was used to visualize risk according to G8 scores. Chi-square tests were used to compare postoperative complication rates according to G8 score or CCI category. RESULTS: A total of 657 patients undergoing radical prostatectomies (n = 372, 56.6%), partial/radical nephrectomies (n = 149, 22.7%), radical cystectomies (n = 76, 11.6%), and nephroureterectomies (n = 60, 9.1%) were included. Complication rates did not significantly differ between patients with CCI scores ≥1 and those with CCI scores of 0 (15.0% vs. 12.4%, p = 0.34). However, the complication rate was significantly higher in patients with G8 scores ≤14 than in those with G8 scores >14 (18.1% vs. 10.5%, p = 0.005). When the OR smoothing curve was used to divide patients into three groups based on G8 scores of <10, 10-14, and > 14, we observed significant differences in complication rates among the groups (37.5% vs. 16.9%. vs. 10.5%; p = 0.001). CONCLUSION: The G8 can aid in predicting postoperative complications in patients ≥65 years old. Comprehensive geriatric assessment is warranted in patients with G8 scores ≤14 prior to major uro-oncologic surgery. Older patients with G8 scores <10 should be counseled regarding the very high risk of surgery.

Role of prostate health index to predict Gleason score upgrading and high-risk prostate cancer in radical prostatectomy specimens.

We evaluated the role of prostate health index (PHI) in predicting Gleason score (GS) upgrading in International Society of Urological Pathology Grade Group (ISUP GG) 1 & 2 prostate cancer (PCa) or adverse pathologic outcomes at radical prostatectomy (RP). A total of 300 patients with prostate specific antigen ≥ 3 ng/mL, PHI and prostate biopsy (71 patients with RP included) were retrospectively included in the study. The primary study outcomes are PCa and clinically significant PCa (csPCa, defined as ISUP GG ≥ 2) diagnostic rate of PHI, and GS upgrading rate at RP specimen. The secondary outcomes are the comparison between GS upgrading and non-upgrading group, GS upgrading and high-risk PCa (ISUP GG ≥ 3 or ≥ pT3a) predictability of preoperative clinical factors. Overall, 139 (46.3%) and 92 (30.7%) were diagnosed with PCa and csPCa, respectively. GS upgrading rate was 34.3% in all patients with RP. Significant differences were shown in the total prostate volume (p = 0.047), the distribution of ISUP GG at biopsy (p = 0.001) and RP (p = 0.032), respectively. PHI values ≥ 55 [Odds ratio (OR): 3.64 (95% confidence interval (CI) = 1.05-12.68, p = 0.042] and presence of PI-RADS lesion ≥ 4 (OR: 7.03, 95% CI = 1.68-29.51, p = 0.018) were the significant predictors of GS upgrading in RP specimens (AUC = 0.737). PHI values ≥ 55 (OR: 9.05, 5% CI = 1.04-78.52, p = 0.046) is a significant factor for predicting adverse pathologic features in RP specimens (AUC = 0.781). PHI could predict GS upgrading in combination with PIRADS lesions ≥ 4 in ISUP GG 1 & 2. PHI alone could evaluate the possibility of high-risk PCa after surgery as well.

Endoscopic Botulinum Toxin Injection for Refractory Enuresis Based on Urodynamic Assessment.

PURPOSE: This study aimed to determine the urodynamic characteristics of refractory enuresis and explored whether those characteristics can be managed through differential endoscopic injections with botulinum toxin. METHODS: In total, 27 patients with nonmonosymptomatic enuresis who showed no response after conservative treatment for more than 12 months were included. The patients then underwent a videourodynamic study and received a differential endoscopic injection of botulinum toxin on the same day. Reduced capacity, detrusor overactivity, and bladder neck widening were the 3 major abnormal findings assessed during the filling phase, while sphincter hyperactivity was the only abnormality assessed during the emptying phase. An intravesical or intrasphincteric injection of botulinum toxin was attempted according to the videourodynamic study findings. Follow-up was conducted at 1, 3, 6, and 12 months after treatment. RESULTS: The median age was 10 years (range, 7-31 years). Although 19 and 8 patients had a preoperative diagnosis of overactive bladder or dysfunctional voiding, respectively, the urodynamic diagnosis was different in more than half of the patients. Those showing detrusor overactivity benefited from intravesical botulinum toxin injection, whereas those with only sphincter hyperactivity benefited from both intravesical and intrasphincteric injections. Treatment resistance to botulinum toxin seemed to be attributable to bladder neck widening. Time had no apparent effect on efficacy, which persisted 6 months after the injection. More than 80% of the patients maintained the benefits of the injection after 1 year. CONCLUSION: Videourodynamic studies were useful for identifying the reasons underlying refractory nonmonosymptomatic enuresis and helpful for determining the appropriate site of botulinum toxin injection.