During skin analysis, which method may be used to observe sub-surface conditions?

• A. Magnifying glass
• B. Dermatologic ultrasound
• C. Wood's lamp
• D. Tape stripping

Answer: (C)

Wood's lamp uses ultraviolet light to make certain substances in the skin fluoresce, so you can see what lies beneath the surface. This lets you observe sub-surface conditions such as fungal infections (which can glow in specific colors), bacterial by-products, and pigmentary changes that aren’t visible under normal lighting. It’s a quick, non-invasive way to map areas of concern during a skin analysis and helps guide treatment decisions.

A magnifying glass mainly enhances surface texture and small details on the outer layer, not what’s happening beneath the surface. Dermatologic ultrasound can image deeper tissues but isn’t typically used in routine beauty analysis, and tape stripping collects a sample from the outer skin layer for lab analysis rather than providing real-time observation of subsurface conditions.