Maximum Voided Volume Research Articles

The value of synchro-cystourethrometry for evaluating the relationship between urethral instability and overactive bladder.

To investigate the correlation between urethral instability (URI) and overactive bladder (OAB) in children. We retrospectively investigated 126 children with OAB and 36 children without OAB using synchro-cystourethrometry. The prevalence of detrusor overactivity (DO) and URI, and the diagnostic sensitivity of DO alone and DO combined with URI, was compared. The OAB children with URI voluntarily received transcutaneous electrical pudendal nerve stimulation with anisodamine (stimulation group, SG) or anisodamine alone (non-stimulation group, NSG). The effectiveness of treatment was evaluated. Average voided volume (AVV), maximum voided volume (MVV), and number of voids per day (NV) were collected and analyzed. In OAB children, the prevalence of DO and URI was 51.6 and 32.5%, respectively. The prevalence of URI was 5.6% in controls. The prevalence of URI was significantly higher in OAB children. The diagnostic sensitivity and Youden index of DO combined with URI were higher than DO alone. In SG, 45.7% of children were cured, with a ≥50% improvement rate of 82.9%, while no child was cured, with a ≥50% improvement rate of 36.8% in NSG. A significant increase in AVV and MVV together, with a decrease in NV, was seen in SG. There was a significant difference in visual analogue scale values between SG and NSG (P<0.01). Urethral instability plays an essential role in the pathogenesis and progression of OAB in children. Synchro-cystourethrometry is a useful urodynamic technology to precisely diagnose OAB, and transcutaneous electrical pudendal nerve stimulation may be an effective treatment for OAB children induced by URI.

A different way to study frequency volume charts in patients with nocturia.

Nocturia results from a mismatch between bladder capacity and nocturnal urine production (NUP), which is determined with a frequency volume charts (FVC). This is the first study that aimed to describe variations in nocturia severity and its associated factors by evaluating FVCs per single 24 h-period. This was a post-hoc analysis of patients who completed a 72 h-FVC in prospective, observational studies. The nocturnal polyuria index (NPi ) was defined as the ratio of nocturnal and 24 h urine output. Subgroups were defined according to variations in nocturia frequency during the three 24 h-periods of the FVC (fluctuating/consistent) and to the number of nocturia episodes during a single night (0/1/≥2). We analyzed 504 24 h-FVC, collected by 168 subjects (58% female) with a median age of 60 (50-68) years. Nocturia frequency fluctuated in 69 (41%) subjects. For the same number of nocturnal voids, we found no differences in NPi and maximum voided volume (MVV) between consistent and fluctuating nocturia frequency. Increasing numbers of nocturnal voids were associated with an increasing NPi in subjects with fluctuating nocturia, while for consistent nocturia, it was linked to an increase in NPi and a decrease in MVV. For both subjects with fluctuating and consistent nocturia, increasing nocturia severity was associated with increasing daytime fluid intake. For the same number of nocturnal voids, bladder capacity, and NUP were similar between patients with consistent and fluctuating nocturia. An increasing number of nocturnal voids in subjects with fluctuating nocturia was linked to more NUP and more daytime fluid intake.

The impact of nerve-sparing robot-assisted radical prostatectomy on lower urinary tract function: Prospective assessment of patient-reported outcomes and frequency volume charts.

To elucidate the effects of a nerve-sparing (NS) procedure on lower urinary tract symptoms (LUTS) and urinary function after robot-assisted radical prostatectomy (RARP), the associations between the NS procedure and LUTS and urinary function were investigated. The participants in this study were 200 consecutive patients who underwent RARP. These patients were categorized into unilateral and bilateral NS groups and the non-NS group. The International Prostate Symptom Score (IPSS), quality of life (QOL) index, frequency-volume chart, uroflowmetry, 1-h pad test, and the 5-item International Index of Erectile Function (IIEF-5) questionnaire were evaluated before and after RARP. The total IPSS score was significantly lower in the unilateral (P = 0.03) and bilateral NS groups (P = 0.03) than in the non-NS group after RARP. Diurnal maximum voided volume (MVV) values were significantly greater in the bilateral NS group than in the non-NS group after RARP (P = 0.002). Nocturnal frequency was significantly decreased in the unilateral NS group than in the non-NS group after RARP (3 months P = 0.01, 12 months P = 0.01). Erectile function was significantly better in both the unilateral NS group (P < 0.0001) and the bilateral NS group (P = 0.02) than in the non-NS group 12 months after RARP. The NS procedure in RARP has the possibility to improve not only erectile function, but also LUTS, owing to both the increase of MVV and the decrease of nocturia. Therefore, the NS procedure is also recommended from the viewpoint of early improvement of LUTS and lower urinary tract dysfunction after RARP.

Complete response to acupuncture therapy in female patients with refractory interstitial cystitis/bladder pain syndrome.

Interstitial Cystitis/Bladder Pain syndrome (IC/BPS) is a considerable issue in urology and gynecology and unfortunately, the treatment options recommended are not fully efficient. Therefore, in this study we aimed to determine the effectiveness of acupuncture treatment in patients with refractory IC/BPS. 12 refractory IC/BPS female patients received ten sessions of acupuncture twice a week. The visual analog score (VAS), interstitial cystitis symptom index (ICSI), interstitial cystitis problem index (ICPI), O'Leary-Saint symptom score (OSS), Patient Health Questionnaire (PHQ9), Pelvic pain and urgency & frequency patient symptom scale tests (PUF) and maximum voided volume (MVV) was completed in 1st, 3rd, 6th and 12th months following the treatment. There was a statistically significant decrease in all of the scores evaluated at first month compared with the baseline. While the change in VAS score in 1, 3, 6 and 12th months were found statistically significant, measurements of ICSI, OSS and PUF scores and MVV values in the 6th and 12th months and ICPI and PHQ scores in the 12th month were not found statistically significant compared to the pre-treatment period. Response to treatment for the first three months after acupuncture application was (100%), but this ratio was measured as 33.3% (4/12) in the sixth month and 16.6% in the 12th month (2/12). The results of this study suggest that acupuncture appears to be an effective, useful, non-invasive method in IC/BPS patients. It can be used as an appropriate treatment method not only in refractory but also in IC patients since it is rather advantageous compared to other treating agents.

The effect of posture and repetition on urodynamic parameters: A prospective randomized study.

PurposeTo evaluate the effect of posture and repetition of filling cystometry on urodynamic parameters.Materials and MethodsSeventy-one men with benign prostatic hyperplasia participated in a urodynamic study between September 2015 and August 2016 and were randomly assigned to a supine to supine (group SS, n=16), erect to erect (group EE, n=16), supine to erect (group SE, n=19) or erect to supine (group ES, n=20) group. The patients underwent filling cystometry twice. We evaluated the effect of posture and the effect of repetition on filling cystometric parameters. We also evaluated the correlation between overactive bladder (OAB) and detrusor overactivity (DO) and between maximum voided volume (MVV) and maximum cystometric capacity (MCC) for each posture and filling cystometry time.ResultsThere was a decrease in bladder sensation and occurrence of DO, and an increase in bladder compliance and MCC in the supine posture group compared to that in the erect posture group. A more significant decrease in bladder sensation and occurrence of DO as well as an increase in MCC was seen during the second filling cystometry than the first one. The supine posture during first filling cystometry showed a better correlation between OAB and DO and between MVV and MCC than erect posture.ConclusionsThere were clear effects of posture and filling cystometry repetition on urodynamic parameters. The supine posture and repeated filling cystometry caused the bladder to be less sensitive and less overactive. The supine posture showed a better correlation to OAB symptoms than erect posture during first filling cystometry.

No immediate effect on urodynamic parameters during transcutaneous electrical nerve stimulation (TENS) in children with overactive bladder and daytime incontinence-A randomized, double-blind, placebo-controlled study.

To evaluate the immediate effect on natural fill urodynamic parameters and bladder function during transcutaneous electrical nerve stimulation (TENS) in children with overactive bladder (OAB) and daytime urinary incontinence (DUI). In this double-blind, placebo-controlled study, 24 children with severe OAB and DUI (mean age 8.5 ± 1.2 years) underwent 48-h natural fill urodynamics. After 24 h of baseline investigation, the children were randomized to either active continuous TENS (n = 12) or placebo TENS (n = 12) over the sacral S2-S3 outflow. The urodynamic recordings were analyzed manually for three different bladder contraction patterns resulting in a void. The number of bladder contractions not leading to a void was also calculated. Maximum voided volume (MVV) and average voided volume (AVV) were identified for both the baseline and the intervention day. We found that TENS had no immediate objective effect on bladder capacity. The difference (before minus after treatment) in MVV/EBC in the active TENS group = 0.03 ± 0.23 versus placebo TENS group = -0.01 ± 0.10 (P = 0.61). Also, there was no significant difference in the proportion of different bladder contraction types between the two groups. TENS did not significantly influence the number of bladder contractions not leading to a void. Results are presented as mean ± SD. There is no immediate objective effect of TENS on bladder activity assessed by natural fill urodynamics in children with OAB and DUI.

Comparison of spinal cord contusion and transection: functional and histological changes in the rat urinary bladder

To compare the effect of complete transection (tSCI) and contusion spinal cord injury (cSCI) on bladder function and bladder wall structure in rats. A total of 30 female Sprague-Dawley rats were randomly divided into three equal groups: an uninjured control, a cSCI and a tSCI group. The cSCI group underwent spinal cord contusion, while the tSCI group underwent complete spinal cord transection. At 6 weeks post-injury, 24-h metabolic cage measurement and conscious cystometry were performed. Conscious cystometry analysis showed that the cSCI and tSCI groups had significantly larger bladder capacities than the control group. The cSCI group had significantly more non-voiding detrusor contractions than the tSCI group. Both injury groups had more non-voiding contractions compared with the control group. The mean threshold pressure was significantly higher in the tSCI group than in the control and cSCI groups. The number of voids in the tSCI group was lower compared with the control group. Metabolic cage analysis showed that the tSCI group had larger maximum voiding volume as compared with the control and cSCI groups. Vesicular acetylcholine transporter/smooth muscle immunoreactivity was higher in the control than in the cSCI or tSCI rats. The area of calcitonin gene-related peptide staining was smaller in the tSCI group than in the control or cSCI groups. Spinal cord transection and contusion produce different bladder phenotypes in rat models of SCI. Functional data suggest that the tSCI group has an obstructive high-pressure voiding pattern, while the cSCI group has more uninhibited detrusor contractions.

Reference values for frequency volume chart and uroflowmetry parameters in adolescent and adult enuresis patients

Reference values of Frequency Volume Chart (FVC) and uroflowmetry parameters for adolescent and adult enuresis patients are lacking. In this study, we aim to describe those parameters, in order to interpret findings from FVCs and uroflowmetries in those patients. Retrospective, descriptive cohort study, concerning 907 patients aged 11 years and older, suffering from enuresis of at least one wet night per fortnight, treated in a secondary/tertiary centre, between 2003 and 2013. The main FVC parameters of interest were: maximum voided volume (MVV), 24 hr urine production and nocturnal urine volume (NUV) including first morning void (FMV). Nocturnal polyuria (NP) was defined based on both International Children's Continence Society (ICCS, 2014) and International Continence Society (ICS, 2002) definitions. Data of all patients were collected from the medical files. Age had an impact on diurnal and nocturnal FVC parameters. Median MVV excluding FMV was 250 ml in the youngest, 11-year-old males and 363 ml in the eldest, ≥18-yr-old males. For females, these values were 230 ml and 310 ml. Median 24 hr urine production increased from 1,025 ml to 1,502 ml (males) and from 1,007 ml to 1,557 ml (females). Median NUV showed an increase from 387 ml to 519 ml (males) and from 393 ml to 525 (females). Forty-two percent of men and 30% of women had a small MVV (for age). Prevalence of NP differed when assessed by the ICS or the ICCS definition: following ICS guidelines, NP was present in 96% of our male and 93% of our female population, compared to 27% and 41%, respectively, following ICCS guidelines. Both small MVV and NP were found frequently in our adolescent and adult enuresis patients, which is in line with the current thoughts on causal factors. NP prevalence is quite different when using ICS or ICCS definitions, respectively. We would like to encourage the development of an unambiguous definition of NP to use both in pediatric and adult urology. Neurourol. Urodynam. 36:463-468, 2017. © 2016 Wiley Periodicals, Inc.

Transcutaneous posterior tibial nerve stimulation in pediatric overactive bladder: A preliminary report

Non-neurogenic overactive bladder (OAB) is a common problem in children that may affect their quality of life. Various methods of neuromodulation have been reported to treat refractory lower urinary tract dysfunction. Since most of these techniques are invasive, they are less applicable in children. To evaluate the efficacy of transcutaneous PTNS in treatment of OAB in children, in a randomized clinical setting. This study was single-blinded, prospective, sham controlled randomized trial. 40 children with non-neurogenic OAB refractory to behavioural and anticholinergic therapy were randomized either to test group or sham group. Neuromodulation was performed using two self-adhesive electrodes cephalad to medial malleolus. In test group the stimulation was given with voltage pulse intensity of 0 to 10 mA, pulse width of 200 μs and frequency of 20 Hz. In sham group patch electrodes were applied to simulate the test group but no stimulation was given. In both groups, weekly session of 30 min was given for a period of 12 weeks. The OAB symptoms, severity of incontinence, number of voids daily (NV), average voided volume (AVV) and maximum voided volume (MVV) were evaluated before and after treatment. On assessment of subjective improvement of OAB symptoms, 66.66% patients reported cure and 23.81% patients reported significant improvement of symptoms in test group whereas in sham group only 6.25% patients reported significant improvement. In test group 71.42% patients reported complete improvement in incontinence whereas in sham group only 12.5% patient reported complete improvement. The AVV, MVV and NV improved significantly in test group (p <0.001) as compared to sham group (Table). The present study is unique as none of the earlier studies in children were sham controlled. It is also first PTNS study in which patch electrodes were used; therefore it is completely noninvasive. This technique provides better patient acceptability and compliance. This study proved that, there is a definite effect of PTNS as compared to placebo because when patients from sham group were treated actively, they responded well. The present study has few limitations as it has relatively short follow-up period of 12 weeks. Relapse of OAB symptoms and maintenance schedule of PTNS need to be assessed further. Transcutaneous PTNS is superior to placebo in treatment of non-neurogenic overactive bladder in children. In view of its effectiveness and acceptability we believe that transcutaneous PTNS should be part of pediatric urology armamentarium for treatment of OAB.

Predictive parameters of response to desmopressin in primary nocturnal enuresis

Many recent treatment guidelines have advocated the importance of a full noninvasive medical evaluation. To individualize treatment, special emphasis must be put on recording of the maximum voided volume (MVV) and nocturnal diuresis in a diary or frequency/volume chart. The aim of this study was to identify any possible predictive factors to desmopressin response. This study is a re-analysis of a prospective, open-label, multinational, phase-IV study evaluating ≤6 months of treatment with desmopressin tablets for children with primary nocturnal enuresis. The children were enrolled between April 2002 and December 2004 from 86 centers in four countries: UK, Canada, Germany and France. A total of 936 children were screened; 744 children aged 5-15 years participated in the study. Of these, 471 children completed the study with 6 months follow-up and recording in a frequency/volume chart. All children experienced six or more wet nights during the 14-day screening period. Exclusion criteria were: organic pathology, treatment for enuresis within the past year, previous treatment for enuresis for >4 weeks, diurnal symptoms, renal or central diabetes insipidus and the use of systemic antibiotics or other drugs known to affect desmopressin activity. The predictive value of number of wet nights a week, fluid intake, daytime voiding frequency and diuresis was investigated by performing a multinomial logistic regression. Of the demographic variables, age was the only significant predictor for response to desmopressin. Controlling for age, the significant predictive variables were: number of wet nights a week, average voided volume daytime, maximum voided volume daytime, total daytime diuresis, nocturnal diuresis (see Figure), maximum voided volume 24h and total 24h diuresis. More than 80% of the children had no nocturnal polyuria and a low maximum voided volume. Performing a secondary analysis is a limitation because the original study was not designed for that. A new prospective study is ethically hardly defendable for children if data are available from previous literature [1]; therefore, a re-analysis was the appropriate choice. The study confirms the predictive value of age, number of wet nights a week and nocturnal diuresis [1,2]. The study demonstrates that desmopressin response rates are higher in children with greater age, limited number of wet nights a week and nocturnal polyuria. Only a minority of a primary nocturnal enuresis population, based on history alone, had nocturnal polyuria. The majority had a low maximum voided volume. The results clearly stress the importance of a frequency/volume chart for individualizing therapy to the characteristics, thereby resulting in elevated success rates. Registration number of clinical trial: Clinical Trials.gov NCT00245479.

Effect of replication-defective herpes simplex virus mediated kynurenine aminotransferase on detrusor overactivity in rats with spinal cord injury

Objective To evaluate if replication-defective herpes simplex virus mediated kynurenine aminotransferase Ⅱ (HSV-KATⅡ) could inhibit detrusor overactivity (DO) in rats with spinal cord injury by bladder wall injection. Methods From June 2012 to July 2013, 48 male Wistar rats with T10 spinal cord transection (SCT) were randomly divided into normal saline group, HSV group and HSV-KATⅡ group (n=16 each group). Normal saline (40 μl), HSV or HSV-KAT Ⅱ(40 μl, 1×107 plaque forming unit viruses) was injected into the rat bladder wall of according group by 1 week after SCT. Three weeks after injection, cystometry was performed and the virus transfected efficiency, expression of KATⅡ in L6–S1 dorsal root ganglia were examined. Results The DO number, DO amplitude, maximum voiding pressure and volume inducing voiding were decreased significantly by 59.6%–61.1%, 21.6%–24.2%, 30.3%–34.4% and 44.1%–46.5% (P 0.05). The relative intensity of KATⅡ protein (0.50±0.13 versus 0.28±0.07, P<0.05) and mRNA (0.78±0.06 versus 0.51±0.08, P<0.01) were increased significantly in HSV-KATⅡgroup than those in HSV group. Conclusion HSV-KATⅡ bladder wall injection inhibits DO and may improve detrusor-sphincter dyssynergia in rats with spinal cord injury. Key words: Spinal cord injuries; Detrusor overactivity; Herpes simplex virus; Kynurenine aminotransferase; Rats, Wistar

Maximum bladder volume as surrogate screening test for detrusor overactivity

Maximum bladder volume could be a simple surrogate measure to screen for detrusor overactivity (DO) which manifests with a frequency and small volume voids. Urodynamic traces from 577 women were reviewed. Maximum bladder volume was obtained from bladder diary. The urodynamic traces were reviewed for data and were categorised as normal, urodynamic stress incontinence, mixed incontinence and DO. The urodynamic data and maximum voided volume were compared between different categories and Receiver operating characteristic (ROC) curves were constructed. The median value for maximum-voided volume for women with DO was not significantly different from the other categories, whereas significant differences were found for the median values for urodynamic variables. ROC curves demonstrated extremely poor sensitivity and specificity for recorded maximum bladder volume and for urodynamic variables. The maximum-voided volume recorded on a three-day bladder diary is not discriminatory as a screening test for DO.

Evaluation of nocturnal bladder capacity and nocturnal urine volume in nocturnal enuresis

ObjectiveTo investigate the diagnostic accuracies of maximum voided volume (MVV) and first morning urine osmolality and compare these with accuracies of nocturnal bladder capacity (NBC) and nocturnal urine volume, respectively, in children with nocturnal enuresis. Materials and methodsA total of 70 children with nocturnal enuresis were assessed (mean age 7.1 ± 2.2 years). Baseline parameters were obtained by measuring MVV using a voiding diary, first morning urine osmolality on a wetting day, diaper weight by checking twice per night and first morning urine volume. ResultsThe proportions of small NBC and small MVV were 34.3% (24 cases) and 55.7% (39 cases), respectively. The proportions of low osmolality of first morning urine and nocturnal polyuria (NP) were 45.7% (32 cases) and 25.7% (18 cases), respectively. The sensitivity and specificity of small MVV for small NBC were 53.8% and 90.3%, respectively; the sensitivity and specificity of first morning urine osmolality for NP were 33.3% and 50.0%, respectively. ConclusionsThe diagnostic accuracies of MVV and urine osmolality for small NBC and NP were only modest to low.

1961 VALIDATION OF AN ELECTRONIC BLADDER DIARY APPLICATION

You have accessJournal of UrologyUrodynamics/Incontinence/Female Urology: Non-neurogenic Voiding Dysfunction1 Apr 20131961 VALIDATION OF AN ELECTRONIC BLADDER DIARY APPLICATION Jerry G. Blaivas, MD James M. Weinberger, BS Jeffrey P. Weiss, andMD Mahyar Kashan BA Jerry G. BlaivasJerry G. Blaivas New York, NY More articles by this author , James M. WeinbergerJames M. Weinberger New York, NY More articles by this author , Jeffrey P. WeissJeffrey P. Weiss Brooklyn, NY More articles by this author , and Mahyar Kashan BAMahyar Kashan BA New York, NY More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.2380AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Bladder diaries are important tools for quantitating lower urinary tract symptoms (LUTS), monitoring therapeutic responses & conducting outcomes research. However, they are underutilized because of the need to carry paper, pen & a measuring device, the time needed to transpose the data, calculate the results & store the diary & summary in the patient's medical record. A bladder diary application solves most of these problems. Herein, we report the content & construct validity of an electronic bladder diary (EBD) app for a PDA (IOS, Android). METHODS Construct validity was achieved by an expert panel using questions from previously validated LUTS questionnaires & diaries. A diary algorithm was constructed for app development. Pre Alpha, white box & black box Alpha testing was done respectively by the developers & expert panel, computer literate & computer naïve patients & healthy volunteers. Content validity was achieved by having users complete the diary in privacy; afterwards, they were interviewed one on one by members of the research team & the app was revised accordingly. RESULTS The PDA app includes a prompt asking for the urge perception score (UPS) for each void, an incontinence question, a nocturia question & 2 voiding questions. The diary app accrues the 24-hour voided volume (VV), day time VV, night time VV, number of voids (day & night), maximum VV, number of incontinent episodes, number of urgency episodes, & a Rho value calculating the correlation between VV & the UPS. The diary and summary (figure 1) can be downloaded as a PDF or XML file. First-time users demonstrated an average time of use for each void of 65 seconds (Range: 45-120 seconds) and time decreased for each successive trial, indicating a very fast learning curve. CONCLUSIONS Users praised the ease of use of the beta version of the EBD. This application could replace traditional bladder diaries in the near future & could ultimately provide a means for patients to become managers of their own symptoms. Traditional bladder diaries present the doctor with a snapshot of a patient's symptoms; sequential use of this EBD could allow the patient to easily provide a reliable portrait of his symptoms over time. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e804-e805 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jerry G. Blaivas New York, NY More articles by this author James M. Weinberger New York, NY More articles by this author Jeffrey P. Weiss Brooklyn, NY More articles by this author Mahyar Kashan BA New York, NY More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

The Effect of Maximum Voided Volume on Response to Desmopressin Therapy in Children with Enuresis

This study was aimed to determine the effect of maximum voided volume (MVV) on the efficacy of desmopressin, which is commonly used to treat primary monosymptomatic nocturnal enuresis (PMNE) in children and adolescents. Bladder capacity was measured with different methods in 52 patients with PMNE, and the effect of bladder capacity on desmopressin therapy was investigated. Patients with PMNE in whom MVV was 70% or less of estimated bladder capacity were found to be unresponsive to desmopressin therapy. The MVV can be measured before desmopressin therapy in patients with PMNE as a marker to predict treatment success. Our results suggest that desmopressin should not be used in patients with low MVV.

Evaluation of maximum voided volume in Korean children by use of a 48‐h frequency volume chart

Study Type - Diagnostic (validating cohort). Level of Evidence 2a. What's known on the subject? and What does the study add? The relationship between the maximum voided volume followed a linear curve. The formula presented, bladder capacity (mL) = 12 ×[age (years) + 11], is thought to be a reasonable one for Korean children. Korean children have a smaller bladder capacity than that reported in previous Western studies. • To develop practical guidelines for the prediction of normal bladder capacity in Korean children measured by a frequency volume chart (FVC), maximum voided volume (MVV) is an important factor in the diagnosis of children with abnormal voiding function. • In all, 298 children, aged 3-13 years, with no history of voiding disorders volunteered for the study. The MVV was determined in 219 subjects by use of a completely recorded FVC. • Linear regression analysis was used to define the exact relationship between age and bladder capacity. An approximate formula related age to bladder capacity as follows: bladder capacity (mL) = 12 ×[age (years) + 11]. • The relationship between the MVV measured by a FVC by age (3-13 years) of Korean children followed a linear curve. • When applied to normal voiding patterns, the formula presented appears to be a reasonable one for Korean children.

Age Related Nocturnal Urine Volume and Maximum Voided Volume in Healthy Children: Reappraisal of International Children's Continence Society Definitions

We determined normal, age related reference data regarding maximum voided volume and nocturnal urine production using the same methodology as in clinical practice. A total of 62 girls and 86 boys without enuresis (mean +/- SD age 9.64 +/- 2.63 years, range 3 to 15) completed 4 days (2 weekends) of frequency-volume charts and 14 days of home recording of nocturnal urine production. From these recordings maximum voided volume with and without first morning void was derived for each subject. Also, average nocturnal urine volume with and without nocturia was calculated. Percentiles were produced by dividing the population into 1-year age groups. Based on 2,836 daytime voids and 1,977 overnight recordings, maximum voided volume and nocturnal urine volume showed a significant linear relationship with age but not with gender. Maximum voided volume with first morning void was significantly higher than without (403 +/- 137 ml vs 281 +/- 112 ml, p <0.0001) and the 50th percentile line of maximum voided volume with first morning void was 80 to 100 ml higher than Koff's formula (30 x [age + 1] ml). Conversely the 50th percentile of maximum voided volume without first morning void was almost identical to Koff's formula. Regarding nocturnal measurements, nocturia was noted on 128 nights (6.5%) and nocturnal urine volume on nights with nocturia was significantly higher than on nights without nocturia (365 +/- 160 ml vs 248 +/- 75 ml, respectively, p <0.0001). The 97.5th nocturnal urine volume percentile line of healthy children deviated markedly from the current International Children's Continence Society definition of nocturnal polyuria, especially at low and high ages. We demonstrate clearly that the universally used formula 30 x (age + 1) ml is indeed valid for a population of healthy Danish children but only if the first morning void is disregarded. Furthermore, we question the validity of the current International Children's Continence Society formula for nocturnal polyuria (nocturnal urine volume greater than 130% of maximum voided volume for age), and instead we propose the formula, nocturnal urine volume greater than 20 x (age + 9) ml.

Normal voiding patterns assessed by means of a frequency–volume chart

Voiding dysfunction is one of the commonest problems among the elderly. This study aimed to elucidate the mechanisms behind the diurnal and nocturnal urine output patterns in young and elderly male volunteers. Of particular interest was bladder reservoir function during the day and night. Young males (n=25; median age 25.0 years; range 22-32 years) and elderly males (n=18; median age 61.1 years; range 55-73 years) were included in the study. Their voiding habits were assessed from a 3-day frequency-volume chart (FVC) detailing all fluid intake and urine output. Data on voided volume, voiding frequency, maximum voided volume (MVV) and average voided volume (AVV) were obtained from the FVC. The young males' average fluid intake was significantly higher than that of the elderly males. On average the elderly males had a slightly higher voiding frequency than the young males, although this was not statistically significant. There was no difference between the two groups regarding their AVVs at night (including the first morning void). The MVVs of the young and elderly males were significantly different, whereas the ratio between voided volume and MVV did not differ between the groups. The main finding was that young and elderly males void with equal average volumes of urine at night (first morning void inclusive), whereas the elderly void with smaller volumes than the young during the day-time. The elderly thus seem to have the capacity to adjust their AVV to night-time urine output size.

Nocturnal Polyuria is Related to Absent Circadian Rhythm of Glomerular Filtration Rate

Monosymptomatic nocturnal enuresis is frequently associated with nocturnal polyuria and low urinary osmolality during the night. Initial studies found decreased vasopressin levels associated with low urinary osmolality overnight. Together with the documented desmopressin response, this was suggestive of a primary role for vasopressin in the pathogenesis of enuresis in the absence of bladder dysfunction. Recent studies no longer confirm this primary role of vasopressin. Other pathogenetic factors such as disordered renal sodium handling, hypercalciuria, increased prostaglandins and/or osmotic excretion might have a role. So far, little attention has been given to abnormalities in the circadian rhythm of glomerular filtration rate. We evaluated the circadian rhythm of glomerular filtration rate and diuresis in children with desmopressin resistant monosymptomatic nocturnal enuresis and nocturnal polyuria. We evaluated 15 children (9 boys) 9 to 14 years old with monosymptomatic nocturnal enuresis and nocturnal polyuria resistant to desmopressin treatment. The control group consisted of 25 children (12 boys) 9 to 16 years old with monosymptomatic nocturnal enuresis without nocturnal polyuria. Compared to the control population, children with nocturnal polyuria lost their circadian rhythm not only for diuresis and sodium excretion but also for glomerular filtration rate. Patients with monosymptomatic nocturnal enuresis and nocturnal polyuria lack a normal circadian rhythm for diuresis and sodium excretion, and the circadian rhythm of glomerular filtration rate is absent. This absence of circadian rhythm of glomerular filtration rate and/or sodium handling cannot be explained by a primary role of vasopressin, but rather by a disorder in circadian rhythm of renal glomerular and/or tubular functions.

Do Holding Exercises or Antimuscarinics Increase Maximum Voided Volume in Monosymptomatic Nocturnal Enuresis? A Randomized Controlled Trial in Children

We assessed prospectively the efficacy of holding exercises and/or antimuscarinics (oxybutynin chloride and placebo) for increasing maximum voided volume in prepubertal children with monosymptomatic nocturnal enuresis. We randomly allocated 149 children to 5 groups, namely holding exercises with placebo (group A), holding exercises with oxybutynin (group B), placebo alone (group C), oxybutynin alone (group D) and alarm treatment (controls, group E). Maximum voided volume was the greatest voided volume from a 48-hour bladder diary, and holding exercise volume was the greatest volume produced with postponement of voiding after a fluid load, once daily for 4 days. Study medication, holding exercise procedures and alarm treatment were administered for 12 weeks. Holding exercises combined with placebo or oxybutynin significantly increased holding exercise volume and maximum voided volume, by 25% (p <0.001) and 21% (p <0.01), respectively, in group A, and by 43% (p <0.001) and 41% (p <0.001), respectively, in group B. Medication without holding exercises (groups C and D) did not increase holding exercise volume or maximum voided volume, and in these groups oxybutynin was not significantly superior to placebo. A borderline increase in holding exercise volume did not affect maximum voided volume in group E. Monosymptomatic nocturnal enuresis response was significantly lower with all 4 holding exercise volume modulating treatments (7%) compared to alarm therapy (73%). In the treatment of children with monosymptomatic nocturnal enuresis maximum voided volume can be increased significantly through holding exercises, but not with oxybutynin chloride alone. Compared to controls, increasing maximum voided volume had a minimal effect on monosymptomatic nocturnal enuresis.