Using spatial frequency domain imaging to monitor a skin biopsy wound: a pilot study

Surgical wound infection is a global postoperative issue adding a significant clinical burden and increasing healthcare costs. Early detection and subsequent diagnosis of infection is vital for accurate, early, and effective treatments. In this paper, we report a pilot study exploring spatial frequency domain imaging (SFDI) to monitor, <i>in-vivo</i>, a biopsy wound in human skin. The reduced scattering coefficient, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mi>μ</mml:mi> <mml:mi>s</mml:mi> <mml:mrow><mml:mi>'</mml:mi></mml:mrow> </mml:msubsup> </mml:math> , absorption coefficient, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>μ</mml:mi> <mml:mi>a</mml:mi></mml:msub> </mml:math> and the oxygen saturation, <i>StO</i> ₂, were measured using a SFDI system at 617 and 850 nm. We found the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mi>μ</mml:mi> <mml:mi>s</mml:mi> <mml:mrow><mml:mi>'</mml:mi></mml:mrow> </mml:msubsup> </mml:math> was better capable of monitoring structural changes, possible pus within the wound, re-epithelialization, and collagen fiber remodeling, than with the eye alone. The <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>μ</mml:mi> <mml:mi>a</mml:mi></mml:msub> </mml:math> map is capable of revealing the total hemoglobin distribution in the wound area but was limited in some regions due to the scab covering. This case study indicates SFDI's potential for monitoring and quantifying the process of surgical wound healing and infection.