Validation of multispectral imaging-based tissue oxygen saturation detecting system for wound healing recognition on open wounds.

Significance: The multispectral imaging-based tissue oxygen saturation detecting (TOSD) system offers deeper penetration ( $\sim 2$ to 3 mm) and comprehensive tissue oxygen saturation ( ${\mathrm{StO}}_2$ ) assessment and recognizes the wound healing phase at a low cost and computational requirement. The potential for miniaturization and integration of TOSD into telemedicine platforms could revolutionize wound care in the challenging pandemic era.

Aim: We aim to validate TOSD's application in detecting ${\mathrm{StO}}_2$ by comparing it with wound closure rates and laser speckle contrast imaging (LSCI), demonstrating TOSD's ability to recognize the wound healing process.

Approach: Utilizing a murine model, we compared TOSD with digital photography and LSCI for comprehensive wound observation in five mice with 6-mm back wounds. Sequential biochemical analysis of wound discharge was investigated for the translational relevance of TOSD.

Results: TOSD demonstrated constant signals on unwounded skin with differential changes on open wounds. Compared with LSCI, TOSD provides indicative recognition of the proliferative phase during wound healing, with a higher correlation coefficient to wound closure rate (TOSD: 0.58; LSCI: 0.44). ${\mathrm{StO}}_2$ detected by TOSD was further correlated with proliferative phase angiogenesis markers.

Conclusions: Our findings suggest TOSD's enhanced utility in wound management protocols, evaluating clinical staging and therapeutic outcomes. By offering a noncontact, convenient monitoring tool, TOSD can be applied to telemedicine, aiming to advance wound care and regeneration, potentially improving patient outcomes and reducing healthcare costs associated with chronic wounds.