Use of hyperspectral imaging to predict healing of diabetic foot ulceration.

Our main objective was to validate that hyperspectral imaging via a new portable camera carries the potential to provide a reliable clinical biomarker that can predict DFU healing. We recruited patients with diabetic foot ulceration (DFU) without peripheral arterial disease, infection or other serious illness. Using an hyperspectral imaging (HSI) apparatus, post-debridement hyperspectral images were taken evaluating the ulcer size, periwound oxyhemoglobin (OxyHb), deoxyhemoglobin level (DeoxyHb) and oxygen saturation (O2 Sat) for four consecutive visits. Twenty-seven patients were followed, out of whom seven healed their DFU while the remaining 20 failed to heal their DFU. The average time between each visit was 3 weeks. Binary logistic regression of healers versus non-healers on Visit 1 oxyHb and on Visit 2 showed a significant inverse association, OR = 0.85 (95% CI: 0.73-0.98, p < 0.001). An inverse correlation was observed between the Visit 1 oxyHb and the percentage of ulcer size reduction between Visit 1 and Visit 4 (r = -0.46, p = 0.02) and between the Visit 2 oxyHb and the percentage of ulcer size reduction between Visits 2 and 4 (r = -0.65, p = 0.001). Using oxyHb 50 as the cut-off point to predict DFU complete healing, Visit 1 oxyHb measurement provided 85% sensitivity, 70% specificity, 50% positive predictive value and 93% negative predictive value. For Visit 2, oxyHb had 85% sensitivity, 85% specificity, 66% positive predictive value and 94% negative predictive value. We conclude that this preliminary study, which involved a relatively small number of patients, indicates that hyperspectral imaging is a simple exam that can easily be added to daily clinical practice and has the potential to provide useful information regarding the healing potential of DFU over a short period of time.

Gas-Producing Infections in the Foot at a Large Academic Medical Center: A 10-Year Retrospective Review.

Gas-producing infections, such as clostridial and nonclostridial gas gangrene, crepitant cellulitis, and necrotizing fasciitis, are characterized in the literature by a variety of initial presentations, microbial burdens and surgical outcomes-ranging from debridement to amputation to death. The primary aim of this study was to identify the organisms cultured in gas-producing infections of the foot in patients that presented to a large academic medical center over a 10-year period. Our secondary aims were to report the prevalence of sepsis in this population upon presentation, and patient outcomes upon discharge. After a retrospective chart review of 207,534 procedures, 70 surgical cases met inclusion criteria. The most common organisms that grew in operating room cultures were Staphylococcus aureus, Group B Beta Streptococcus, and Enterococcus species. Just over half of the population presented with sepsis. After an average of 2 or more operations, 64% of patients underwent amputation. One death occurred. Gas-producing infections, or "gas gangrene," are primarily polymicrobial infections, rarely due to Clostridium perfringens, that warrant surgical exploration for optimal outcomes.

The role of collagen bioscaffolds, foamed collagen, and living skin equivalents in wound healing.

Collagen is one of the fundamental building blocks of skin and plays a critical role in wound healing. This article looks at the wide array of collagen and living skin equivalent products containing collagen and living cells, and at how these may be used in the treatment of diabetic foot ulcers. Solid collagen, foamed collagen, living skin equivalents, and living cadaveric skin are considered. Clinical examples are included, along with a brief discussion of wound dressings that may help to enhance the incorporation of these materials.