1. What is BSA Calculation for Psoriasis?

Definition: Body Surface Area (BSA) calculation estimates the percentage of skin affected by psoriasis using the palm method.

Purpose: It helps dermatologists and patients assess psoriasis severity and track treatment progress.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• 1 palm = approximately 1% of total body surface area
• Patient's palm (including fingers) is used as measurement unit

Explanation: Count how many palm-sized areas are affected by psoriasis to estimate total BSA involvement.

3. Importance of BSA Calculation

Details: BSA measurement helps classify psoriasis severity:

• Mild: <3% BSA
• Moderate: 3-10% BSA
• Severe: >10% BSA

4. Using the Calculator

Tips:

• Examine all body areas (including scalp, nails, genitals)
• Use patient's own palm for measurement
• Round to nearest whole number

5. Frequently Asked Questions (FAQ)

Q1: Why use the palm method?
A: It's simple, quick, and doesn't require special tools - ideal for clinical practice.

Q2: How accurate is this method?
A: While not as precise as digital tools, it provides reliable estimates for treatment decisions.

Q3: What about very small or large lesions?
A: Combine smaller lesions to make "palm-sized" areas, or estimate fractions of palms.

Q4: Does this include non-visible areas?
A: Yes, all affected areas should be counted, even if not normally visible.

Q5: How often should BSA be measured?
A: At each clinical visit to monitor treatment response, typically every 3-6 months.