1. What is a Bladder Volume by Age Calculation?

Definition: This calculator estimates bladder volume using ultrasound measurements (length, width, height) adjusted for age-related norms.

Purpose: It helps medical professionals assess bladder capacity and diagnose urinary conditions in patients of different ages.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( V \) — Volume of bladder (cm³)
• \( L \) — Length measurement (cm)
• \( W \) — Width measurement (cm)
• \( H \) — Height measurement (cm)
• Age factor — Adjustment for pediatric or geriatric patients

Explanation: The formula calculates bladder volume as an ellipsoid, then applies age-specific adjustment factors.

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 adjustment factor (default 1.0 for adults). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why use the ellipsoid formula?
A: The bladder's shape approximates an ellipsoid, making this formula more accurate than simple length×width×height.

Q2: What are typical age adjustment factors?
A: Children (0.7-0.9), Adults (1.0), Elderly (0.8-0.9). Consult clinical guidelines for specific values.

Q3: How accurate is this calculation?
A: ±10-15% compared to catheterized volumes, but provides good clinical estimate for non-invasive assessment.

Q4: What's normal bladder capacity?
A: Adults: 400-600 mL; Children: (Age + 1) × 30 mL; but varies by individual.

Q5: When would post-void residual be important?
A: For diagnosing urinary retention, compare calculated volume with post-void ultrasound measurements.