1. What is Bladder Volume Estimation by Ultrasound?

Definition: This calculator estimates bladder volume using ultrasound measurements of the bladder's length, width, and height, assuming an ellipsoid shape.

Purpose: It helps medical professionals assess bladder volume non-invasively, useful for diagnosing urinary retention or monitoring bladder function.

2. How Does the Calculator Work?

The calculator uses the ellipsoid volume formula:

Where:

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

Explanation: The formula calculates the volume of an ellipsoid, which approximates the shape of a filled bladder.

3. Importance of Bladder Volume Measurement

Details: Accurate bladder volume estimation helps diagnose conditions like urinary retention, assess post-void residual volume, and guide catheterization decisions.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this estimation method?
A: It's generally within 10-20% of actual volume, though accuracy depends on bladder shape and measurement precision.

Q2: What's a normal bladder volume?
A: Typically 300-500 mL when full, but varies by individual. Over 500 mL may indicate retention.

Q3: Can I use this for pediatric patients?
A: Yes, but normal volumes will be smaller. The formula works the same way.

Q4: How do I convert cm³ to mL?
A: They're equivalent (1 cm³ = 1 mL), so no conversion needed.

Q5: What if my ultrasound machine has built-in calculations?
A: Those are typically more accurate as they may use machine-specific algorithms.