1. What is a Prostatic Volume Calculator?

Definition: This calculator estimates prostate volume using the ellipsoid formula based on length, width, and height measurements from imaging studies.

Purpose: It helps radiologists and urologists assess prostate size, which is important for diagnosing benign prostatic hyperplasia (BPH) and planning treatments.

2. How Does the Calculator Work?

The calculator uses the ellipsoid formula:

Where:

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

Explanation: The formula approximates the prostate as an ellipsoid and calculates its volume using the three orthogonal measurements.

3. Importance of Prostatic Volume Calculation

Details: Accurate volume measurement helps in assessing prostate enlargement, planning surgical interventions, and determining PSA density (PSA divided by prostate volume).

4. Using the Calculator

Tips: Enter the length, width, and height measurements obtained from transrectal ultrasound (TRUS), MRI, or CT imaging. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why use the ellipsoid formula?
A: It's the most widely used method in clinical practice as it provides a good approximation of prostate volume with simple measurements.

Q2: What's a normal prostate volume?
A: Typically 20-30 cm³ in young men, often increasing with age (may exceed 100 cm³ in BPH).

Q3: How accurate is this method?
A: It's about 80-90% accurate compared to planimetry (the gold standard), but much faster to perform.

Q4: Should measurements be in any particular order?
A: No, since multiplication is commutative, but standard practice is anteroposterior (height) × transverse (width) × craniocaudal (length).

Q5: How is this different from PSA?
A: PSA is a blood test for prostate-specific antigen, while volume is a physical measurement. PSA density (PSA/volume) is often more clinically meaningful than PSA alone.