1. What is a Prostate PSA Volume Calculator?

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

Purpose: It helps urologists calculate prostate volume for PSA density assessment, which aids in prostate cancer risk evaluation.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( V \) — Prostate volume (cubic centimeters)
• \( L \) — Length (cm)
• \( W \) — Width (cm)
• \( H \) — Height (cm)

Explanation: The prostate is modeled as an ellipsoid, and the formula calculates its volume based on three orthogonal measurements.

3. Importance of Prostate Volume Calculation

Details: Prostate volume is essential for calculating PSA density (PSA divided by volume), which helps distinguish between benign prostatic hyperplasia and potential prostate cancer.

4. Using the Calculator

Tips: Enter the prostate dimensions (length, width, height) in centimeters as measured by TRUS or MRI. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What imaging methods provide these measurements?
A: Transrectal ultrasound (TRUS) or MRI are most commonly used to measure prostate dimensions.

Q2: How accurate is this ellipsoid formula?
A: It provides a good estimate (within 10-15% of actual volume) for most prostate shapes, though planimetry may be more accurate for irregular shapes.

Q3: What is a normal prostate volume?
A: Typically 20-30 cm³ for young men, often increasing with age (may reach 40-60 cm³ in benign prostatic hyperplasia).

Q4: How is PSA density calculated?
A: PSA (ng/mL) divided by prostate volume (cm³). Normal is typically < 0.15 ng/mL/cm³.

Q5: Why not use weight instead of volume?
A: Volume correlates better with PSA production and is more practical to measure non-invasively.