Skin Impedance
The opposition of the skin to electrical current flow, measured to assess hydration, barrier integrity, and suitability for energy-based treatments.
Full Definition
Skin impedance is a biophysical parameter expressing the total resistance of the skin to alternating electrical current, incorporating both resistive and capacitive components. In aesthetic dermatology, it is used as a surrogate marker for stratum corneum hydration, epidermal barrier function, and as a pre-treatment safety check before radiofrequency or electroporation-based procedures. Editors working on device clinical data or cosmeceutical efficacy papers must understand that skin impedance values are frequency-dependent and should be reported with the measurement frequency specified. The term must not be confused with 'transepidermal water loss' (TEWL), which measures outward water flux rather than electrical resistance. Lower impedance generally indicates higher moisture content, a counterintuitive direction that editors should verify is stated correctly in manuscripts.
Usage
Usage note: Ensure that measurement frequency (in Hz or kHz) is reported alongside impedance values; without this, the data are not reproducible.
In Context
- "Baseline skin impedance measurements were taken at 100 kHz to ensure equivalent hydration status across treatment groups." — Clinical study methods section
- "The author had conflated skin impedance with TEWL; the editor inserted a clarifying note distinguishing the two parameters." — Manuscript correction note