Evaluation of Fluorescence-image Guided Wound Assessment vs. Standard Practice

Chronic wounds and their associated care are a burden to patients and health care systems worldwide. Microbiological testing of wound samples is often used to identify and quantify bacterial species, the latter of which may be both an objective quantitative indicator of infection and a predictive correlate of healing. Microbiology reports contain useful information about microbial identities, antibiotic susceptibility, and semi-quantitative bacterial growth rates, but these data typically represent the bacterial load in the wound centre only, and often arrive 3-5 days later. There is an unmet clinical need to improve the microbiological sampling and treatment of wound infections. To address this need, we developed a handheld portable imaging device that obtains white light (WL) and fluorescence (FL) images (or video) of normal skin and wounds in high-resolution and in real-time, which can be used at the point-of-care. It was demonstrated in previous studies that the device1) provides image-guidance for tissue sampling, detecting clinically-significant levels of pathogenic bacteria and wound infection otherwise overlooked by conventional sampling and 2) provides image-guidance for wound treatment, accelerating wound closure compared with conventional therapies and quantitatively tracking long-term changes in bacterial bioburden and distribution in wounds.

The current trial aims to compare the assessment of diabetic foot ulcers by fluorescence image guidance to standard practice. The device will be used to acquire fluorescence images of diabetic foot ulcers: when wounds are illuminated by violet/blue light, most pathogenic bacterial species emit a unique red fluorescence signal. The device is intended to be used as part of the clinical assessment process, which may include visual assessment, signs of heat or high temperature, the presence of exudate, and redness in the area. Images will guide the clinician to inspect, sample or further evaluate areas where fluorescing bacteria is present. This study will allow us to determine the benefit of fluorescence image-guided procedure as compared to standard clinical practice to assess bacterial burden in diabetic foot ulcers. Microbiological swabbing under standard practice and fluoresce-guided imaging will be performed in order to compare the two techniques.