Mid-infrared spectroscopic imaging to assess wounded tissue health

Modern traumatic injuries, as encountered in battlefield conflicts, are often characterised by extensive soft tissue damage from blasts and high energy projectiles. This situation has created a challenge for wound stabilisation and repair, with surgical intervention common, via wound debridement procedures. These are often complex surgeries where necrotic and infected tissue is removed, usually with multiple remedial surgeries, designed to aid the natural healing process and to reduce the likelihood of infection. With extensive injuries, the preservation of viable tissue is paramount to functional recovery. Additionally, identifying wounds which are likely to heal without intervention, as well as those that exhibit precursors for impaired healing or infection, would assist in informing the appropriate medical care. Technologies that utilise concepts of non-contact imaging, such as optical imaging and spectroscopy can be used to obtain spatial and spectral maps of biomarkers, which provide valuable information on the wound (e.g. precursors to improper healing or delineate viable and necrotic tissue). A negative contrast imaging device (NCI) has been shown to characterise wound biopsies, through mid-IR (2.6 - 4 μm) non-invasive spectroscopic imaging. To better demonstrate the applicability of this technique, wound relevant cell cultures, subjected to induced trauma, are used to identify spectral changes between healthy and traumatised cells. This work highlights the available contrast in spectroscopic mid-IR signals and demonstrates the utility of spatially and spectrally derived maps as an assessment tool for wound diagnostics.