Design of a Skin Grafting Methodology for Burn Wound Using an Additive Biomanufacturing System Guided by Hyperspectral Imaging

Skin thermal burn wounds are classified by depth and require different levels of medical intervention. In this paper, the authors propose a novel treatment method where hyperspectral imaging (HSI) is applied to measure skin burn wound information that guide an additive biomanufacturing process to print a custom engineered skin graft in three dimensions (3D). Two dimensional principle component analysis (2DPCA) for noise reduction is applied to images captured by HSI in the visible wavelength range from 375 nm to 750 nm. A multivariate regression analysis is used to calculate hemodynamic biomarkers of skin burns, specifically the total hemoglobin concentration (tHb) and oxygen saturation (S_tO₂) of the injured tissue. The biomarker results of the skin burn images are mapped spatially to show the burn wound depth distribution. Based on the biomarker values, the burn area is segmented into different sub areas with different burn degrees. Depth profiles of deep burns which require skin grafting are extracted from the burn distribution map. Next, each profile is processed to generate an additive biomanufacturing toolpath with a prescribed internal tissue scaffold structure. Using the toolpath, a 3D printer processes a custom graft from an alginate polymer hydrogel material. Alginate is chosen as the print material since it can be stretched into aligned fibers to create a porous structure that facilitates oxygen and nutrient uptake. The resultant printed construct demonstrates the feasibility of fabricating patient-specific tissues with custom-geometry grafts for treating clinical burns.