1. What is a Bladder Size Calculator by Age?

Definition: This calculator estimates bladder volume based on ultrasound measurements (length, width, height) adjusted by age-specific factors.

Purpose: Helps medical professionals assess bladder capacity and detect abnormalities in patients of different ages.

2. How Does the Calculator Work?

The calculator uses the ellipsoid formula:

Where:

• \( V \) — Volume of bladder (cm³)
• \( L \) — Length measurement (cm)
• \( W \) — Width measurement (cm)
• \( H \) — Height measurement (cm)
• \( A \) — Age adjustment factor

Explanation: The ellipsoid formula calculates bladder volume, then adjusted by age-specific norms.

3. Importance of Bladder Volume Calculation

Details: Accurate bladder volume assessment helps diagnose conditions like urinary retention, overactive bladder, and neurogenic bladder dysfunction.

4. Using the Calculator

Tips: Enter ultrasound measurements in cm and select appropriate age factor (default 1.0 for adults). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why do we need an age factor?
A: Bladder capacity changes with age - children have smaller bladders that grow proportionally with age.

Q2: What are typical age factors?
A: Newborns (0.1), 1-2 years (0.3), 3-6 years (0.5), 7-12 years (0.7), teens (0.9), adults (1.0).

Q3: How accurate is this calculation?
A: The formula provides an estimate within 10-15% of actual volume when proper measurements are taken.

Q4: What's normal bladder capacity?
A: Adults typically 400-600 mL; children: age in years × 30 + 30 = capacity in mL.

Q5: When would this calculation be used?
A: For pre- and post-void residual measurements, assessing bladder training progress, and evaluating urinary symptoms.