Related Experiment Video
Updated: Feb 10, 2026
Real-Time Void Spot Assay
Published on: February 10, 2023
Can recording only the day-time voided volumes predict bladder capacity?
Won Yeol Cho1, Seong Cheol Kim2, Sun-Ouck Kim3
1Department of Urology, Dong-A University College of Medicine, Busan, Korea.
Insights
This study shows that estimating maximal voided volume using daytime voided volumes (MVVDT x 1.25) is a reliable method for assessing bladder capacity, especially for children with nocturnal enuresis.
Area of Science:
- Pediatric Urology
- Bladder Function Assessment
Background:
- Assessing bladder capacity is crucial for diagnosing and managing pediatric lower urinary tract dysfunction.
- Traditional methods like the first morning void (FMV) can be unreliable in children with nocturnal enuresis.
Purpose of the Study:
- To establish an easy method for assessing bladder capacity using daytime voided volumes.
- To validate the estimation of maximal voided volume (MVV) using daytime measurements in healthy children.
Main Methods:
- Evaluated 177 healthy children using frequency-volume charts (FVC) over 48 hours.
- Measured daytime voided volumes and compared them to the first morning void (FMV).
Main Results:
- Daytime voided volumes typically ranged from 30% to 80% of the maximal voided volume (MVV).
- Maximal voided volume during daytime (MVVDT) was significantly lower than MVV (179.5±71.1 mL vs. 227.0±79.2 mL).
- A strong correlation (r=0.801) was found between MVV and estimated MVV using MVVDT x 1.25.
Conclusions:
- Estimating bladder capacity using MVVDT x 1.25 provides a reliable alternative when FMV is unavailable.
- This method is particularly useful for patients with nocturnal enuresis, improving bladder capacity assessment.
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.
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