1. What is Bladder Volume Calculation?

Definition: This calculator estimates bladder volume using the ellipsoid formula based on three-dimensional measurements from ultrasound or CT imaging.

Purpose: It helps radiologists and urologists assess bladder capacity, detect abnormalities, and evaluate post-void residuals.

2. How Does the Calculator Work?

The calculator uses the ellipsoid formula:

Where:

• \( V \) — Bladder volume (cm³)
• \( L \) — Maximum length (cm)
• \( W \) — Maximum width (cm)
• \( H \) — Maximum height (cm)

Explanation: The formula approximates the bladder as an ellipsoid shape, which is the standard method in radiological practice.

3. Importance of Bladder Volume Measurement

Details: Accurate volume estimation helps diagnose conditions like urinary retention, overactive bladder, and monitors treatment effectiveness.

4. Using the Calculator

Tips: Enter the three orthogonal measurements (length, width, height) in centimeters from imaging studies. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: The ellipsoid formula has about 90% accuracy for normal bladders, but may be less accurate for irregular shapes.

Q2: What's a normal bladder volume?
A: Typically 400-600 cm³ in adults, but varies with age, gender, and hydration status.

Q3: When would this calculation be used?
A: For pre- and post-void residual measurements, assessing bladder capacity, and evaluating urinary retention.

Q4: Can this be used for pediatric patients?
A: Yes, but normal values differ significantly by age and body size in children.

Q5: How does this compare to other volume estimation methods?
A: The ellipsoid method is most common, but some use the prolate ellipsoid (0.52×L×W×H) or automated 3D measurements.