It is time to abandon “Expected bladder capacity.” Systematic review and new models for children's normal maximum voided volumes

Bladder capacity in an elimination communication infant: a case report

BACKGROUND

Bladder capacity is essential in assessing children with voiding dysfunction, yet it is currently unclear how best to determine a benchmark bladder capacity; various formulas have been proposed.

CASE PRESENTATION

This report details the unique case of an elimination communication Caucasian infant (< 2 years old) who achieved nighttime and daytime dryness by 6 months of age. His first morning voids were measured from 8 to 20 months of age and compared with three formulas: (1) the Koff formula, a widely used formula based on fill volumes in anesthetized infants; (2) the Kaefer formula, a formula based on fill volume in nonanesthetized infants; and (3) the Holmdahl formula, a formula based on frequency-volume charts in normal infants.

CONCLUSION

This infant's first morning void was found to be most consistent with Kaefer's formula. Further research is required to determine if formulas based on fill volume in nonanesthetized infants provide the more accurate benchmark bladder capacity in infants.

Lower urinary tract effects of ureteral stent length and intravesical position

PURPOSE

Ureteral stents can cause lower urinary tract problems such as stent-related irritative symptoms and urinary tract infections. This study aimed to determine the lower urinary tract effects of ureteral stent length and intravesical position in children.

METHODS

Patients who underwent double-J stenting after urological procedures between January 2017 and January 2022 were included in the study. The patients were assessed in terms of age, irritative symptoms, urinary tract infections, and stent length. The intravesical position of the ureteral stents was grouped as cross-trigonal and ipsilateral. The distribution of irritative symptoms, frequency of urinary tract infections and stent length were analyzed according to intravesical location.

RESULTS

A total of 47 patients were included in the study. The median age was 5 years (range: 1-16). Cross-trigonal stent position was significantly associated with symptoms of urgency (p = 0.046), suprapubic pain (p = 0.002), and lower mean age (p = 0.004). Urinary tract infections were more frequent in patients whose placed stents were longer than recommended (p < 0.001) or were in cross-trigonal position (p = 0.043).

CONCLUSION

Our results suggest that stent-related irritative symptoms and urinary tract infections can be reduced in pediatric patients using a suitably sized ureteral stent and considering its intravesical position.

[Special diagnostics in pediatric urology-Nuclear medicine diagnostics, advanced diagnostics for bladder voiding disorders and imaging diagnostics in the operating room : Tips for the practice part 2]

The diagnostics and treatment of pediatric urology patients in the clinical routine can be extremely challenging. In contrast to adult patients, the main concerns in the diagnostics of congenital diseases are time consuming examinations and limited options in addition to the expectations of the parents. The exact knowledge of the diagnostic possibilities in association with the correct interpretation of the indications is essential. Simple processes can be much more time consuming because of a lack of compliance, especially in very young children. Sonography is considered the standard for imaging in pediatric urology. Profound knowledge of the embryonal development and also physiological processes throughout childhood contribute to making the correct diagnosis. This article deals with the possibilities of nuclear medicine diagnostics, advanced diagnostics in bladder voiding disorders and finally imaging diagnostics in the pediatric urological operating room.

The Importance of Understanding Parental Perception When Treating Primary Nocturnal Enuresis: A Topic Review and an Institutional Experience

Primary nocturnal enuresis (PNE) is a common childhood disorder that adversely affects a child’s mental well-being and social life. Our clinical experience showed parents and their child often have significantly different perspective of enuresis, and these differences can affect family dynamics, treatment approaches, and treatment success. Parents’ perception of PNE also influences the likelihood of seeking medical treatment, and we found parents of children with enuresis have markedly different beliefs regarding bedwetting than those of physicians. Because achieving remission for PNE requires parents and their child to actively participate in treatment, assessing their expectancy of success and their beliefs will allow clinicians to adjust treatment goals as necessary. When treating PNE, guidelines consistently recommend incorporating bed alarms as part of the therapy. However, through interviewing parents and treating their children, we found parents preferred medications or other behavioral strategies, such as limiting water intake, because of their convenience. Many parents would complain bed alarms woke them up instead of their child, and they would soon give up on bed alarms. Part of assessing their beliefs includes assessing their confidence in their child being able to wake up to alarms and to persist with treatment. Understanding how they manage and approach setbacks will also determine the treatment modality suited for their child. In this review paper, we detailed our experiences interviewing parents and treating their child with NE with urodynamics and medications at the Changhua Christian Hospital in Taiwan.

Non-invasive bladder function measures in healthy, asymptomatic female children and adolescents: A systematic review and meta-analysis

BACKGROUND

Lower urinary tract symptoms (LUTS) are common in children and adolescents. Non-invasive tests evaluating bladder function are generally preferred over invasive tests, yet few studies have explored the range of normative values for these tests in healthy, asymptomatic children.

OBJECTIVE

To define normative reference ranges for non-invasive tests of bladder function in healthy, asymptomatic girls and adolescents.

STUDY DESIGN

A comprehensive search strategy was performed in seven electronic databases through October 2019. English-language studies reporting data on voiding frequency, voided and postvoid residual volumes (PVR) and uroflowmetry results in healthy, asymptomatic girls (mean age ≥ 5 years) were included. Two independent reviewers performed study review, data extraction, and quality assessment. Overall mean estimates and 95% confidence intervals for each bladder function parameter were calculated using random effects models, and 95% normative reference values were estimated.

RESULTS

Ten studies met eligibility criteria for the meta-analysis (n = 2143 girls, age range: 3-18). Mean estimates of maximum voided volume and PVR were 233.4 ml (95% CI 204.3-262.6; n = 1 study) and 8.6 ml (95% CI 4.8-12.4; n = 2 studies) respectively. Pooled mean estimates for uroflowmetry parameters were: 21.5 ml/s (95% CI 20.5-2.5) for maximum flow rate (n = 6 studies), 12.5 ml/s (95% CI 11.2-13.8) for mean flow rate (n = 6 studies), 6.8 s (95% CI 4.4-9.3) for time to maximum flow (n = 3 studies), 15.7 s (95% CI 13.0-18.5) for flow time (n = 3 studies), and 198.7 ml (95% CI 154.2-234.2) for voided volume (n = 9 studies). No studies reported estimates of voiding frequency. Between-study heterogeneity was high (89.0-99.6%).

CONCLUSIONS

Although we were able to calculate pooled mean estimates for several parameters, the small number of included studies and the wide age ranges of participants preclude generalization of reference values to all healthy girls. Further research is needed to determine normative reference values within specific age groups.

Dynamic Changes in Bladder Morphology Over Time in Cervical Cancer Patients

Objectives:

Continuous surveillance of bladder volume (BV) is beneficial during the treatment of various urogenital diseases because the bladder is always changing its position, size and even shape at different filling phases. For this purpose, we quantified the motion of the urinary bladder.

Methods:

Daily ultrasound measurements and weekly cone-beam computed tomography scans were obtained from 89 patients in the supine position. BV, bladder centroid positions, and triaxial lengths in the left-right (LR), anterior-posterior (AP), and superior-inferior (SI) directions were compared across different time points.

Results:

BV linearly increased over time, and the mean urinary filling rate (v_tot) was correlated with the patients’ age and water consumption. The greatest bladder centroid motion occurred longitudinally, with less movement observed laterally. The maximum bladder centroid movement was 18.8 ± 2.2 mm inferiorly and 1.8 ± 0.9 mm posteriorly for every 10% decrease in BV. The rates of changes in triaxial lengths differed across the 4 filling phases. The rate was the largest at a BV range of 10-80 mL, especially in the LR direction, with values of 5.9 ± 1.0, 3.6 ± 1.0, and 3.9 ± 1.0 mm per every 10-mL BV increase for LR, AP, and SI, respectively. With bladder filling (<80 mL), the maximum increase in triaxial length was observed in the SI direction and the rates of all changes considerably decreased, especially at BV > 600 mL.

Conclusion:

The v_tot could be used to evaluate the temporal changes in the bladder. The spatial changes should be assessed according to different filling phases based on the centroid position and triaxial lengths.

Can recording only the day-time voided volumes predict bladder capacity?

Purpose

This study aimed to demonstrate a method to easily assess bladder capacity using knowledge of day-time voided volumes, which can be obtained even from patients with nocturnal enuresis where the first morning void cannot accurately predict the bladder capacity due to bladder emptying overnight.

Materials and Methods

We evaluated 177 healthy children from 7 Korean medical centres entered the study between January 2008 and January 2009. Voided volumes measured for more than 48 hours were recorded in the frequency volume chart (FVC).

Results

Most voided volumes during day-time were showed between 30% and 80% of the maximal voided volume (MVV). The maximal voided volume during day-time (MVVDT) was significantly less than the MVV (179.5±71.1 mL vs. 227.0±79.2 mL, p<0.001). The correlation coefficients with the MVV were 0.801 for the estimated MVV using the MVVDT (MVVDT×1.25), which suggested a fairly strong relationship between the MVVDT×1.25 and the MVV.

Conclusions

The MVV derived from the FVC excluding the FMV was less than if the FMV had been included. When an accurate first morning voided volume cannot be obtained, as in patients with nocturnal enuresis, calculating MVVDT×1.25 allows estimation of the bladder capacity in place of the MVV.

Bladder rupture after voiding cystourethrography: A case report and literature review on pitfalls and bladder volume estimation

Voiding cystourethrography (VCUG) is a common diagnostic study in pediatric urology. Although generally considered a safe procedure, VCUG can incur some complications. Bladder rupture following VCUG is a very rare complication and mostly happens in the setting of unused bladders, previous surgeries, or underlying disease. The rupture is almost always intraperitoneal needing prompt surgical treatment. We present a unique case of extraperitoneal bladder rupture after VCUG in an 8-month-old boy. The rupture remained unnoticed and the patient recovered spontaneously without medical or surgical intervention. To the best of our knowledge, this is the first such case report in the English literature. The information provided may guide clinicians on the proper use of bladder volume formulas in children and also help them in getting a proper VCUG study.