Grant: Project Grant

Patients with diabetes are 20 times more likely to have a lower limb amputation than the general population. This amputation rate is even higher when the patient has a diabetic foot ulcer. Currently, we have no tools that can give an early warning about the tissue health of diabetic legs and feet. This means that patients come to the hospital in many cases too late to save their foot or toes. Magnetic resonance imaging (MRI) is a very powerful imaging tool. It can see blockages in arteries, measure blood flow to tissue, and, it is very sensitive to measuring a blood product called methemoglobin. Methemoglobin is a marker of free radicals, which is also known to tell us about the poor outcome in tissues. Unfortunately, MRI is fairly expensive so is not used for screening. If there were an early warning tool, we might be able to see disease earlier, intervene earlier, save more limbs, and improve these patient's lives. We are developing an early warning tool in our labs. The device is called Multispectral Imaging (MSID). The MSID device takes pictures of tissue using different "colors" of infrared light. By comparing these pictures, we can tell how much blood and tissue damage exists in the leg and foot of diabetic patients. In our studies, we will first evaluate how well our device is able to measure these signals of tissue damage in standardized laboratory models. Then we will evaluate how well the early warning device compares to MRI for tissue injury. We will then test our early warning device in a group of patients who have normal blood flow, blocked blood flow, and in patients with foot wounds. The information obtained from the patient study will then be used to design the next generation device. This device is a small, hand held device that can assess tissue health at home. By early recognition and screening, we may be able to save limbs and lives.