Optical tracking of local surface wave for skin viscoelasticity

Area of Science:

• Biomedical Engineering
• Dermatology
• Materials Science

Background:

• Accurate biomechanical property assessment is vital for diagnosing skin thermal injury.
• Viscoelasticity quantification is a key method for determining these properties.
• Existing methods may lack speed and efficiency for rapid clinical assessment.

Purpose of the Study:

• To develop and validate a rapid optical method for quantifying skin viscoelasticity.
• To introduce novel elastic and viscous coefficients for skin characterization.
• To assess the sensitivity of the method in detecting thermal injury-induced changes.

Main Methods:

• Optical tracking of local surface waves generated by a single impulse.
• Utilizing a vibrator with a ball-tipped device for impulse generation.
• Employing laser Doppler vibrometry for surface wave detection.
• Using ultrasound for monitoring depth-wise skin motion and multi-layered properties.

Main Results:

• The proposed method successfully determined skin viscoelasticity in porcine samples.
• Ultrasound confirmed multi-layered viscoelasticity of the epidermis and dermis.
• Novel coefficients showed variations in healthy porcine skin.
• A slight burn significantly increased the coefficients in one sample, indicating sensitivity.

Conclusions:

• The developed optical surface wave tracking method is sensitive, effective, and rapid for determining skin viscoelasticity.
• This technique holds potential for improved diagnosis and monitoring of skin thermal injuries.
• The proposed coefficients offer a new metric for assessing skin's mechanical response.