The Use of Medical Hyperspectral Technology to Evaluate Microcirculatory Changes in Diabetic Foot Ulcers and Predict Clinical Outcomes Received for publication 26 October 2006 and accepted in revised form 8 January 2007. Short title: Hyperspectral Technology in Diabetic Foot Ulceration

Background: Foot ulceration (DFU) is a serious complication of diabetes and new techniques that can predict wound healing may prove very helpful. We tested the ability of Medical Hyperspectral Technology (HT), a novel diagnostic scanning technique which can quantify tissue oxyand deoxyhemoglobin, to predict DFU healing. Methods: Ten T1DM patients with 21 foot ulcer sites, 13 T1DM without ulcers and 14 non-diabetic controls were seen up to four times over a 6-month period. HT measurements of oxyhemoglobin (HT-Oxy), deoxyhemoglobin (HT-Deoxy) were performed at or near the ulcer area, and on the upper extremity and the lower extremity distant from the ulcer. A HT-Healing Index for each site was calculated from the HT-Oxy and HT-Deoxy values. Results: Hyperspectral tissue oxygenation measurements observed changes in tissue immediately surrounding the ulcer when comparing ulcers that heal and ulcers that do not heal (p <.001). The sensitivity, specificity, positive predictive and negative predictive value of the HT Index to predicting healing were 93%, 86%, 93% and 86% when evaluated on images taken at the first visit. Changes in HT-Oxy among the three risk group were noted for the metatarsal area of the foot (p <.05) and the palm (p <.01). Changes in HTDeoxy and HT Healing Index were noted for the palm only (p <.05 and p <.01, respectively). Conclusions: HT has the capability to identify microvascular abnormalities and tissue oxygenation in the diabetic foot and predict ulcer healing. HT can assist in the management of foot ulceration