3.7m people in the UK and 422m worldwide have diabetes. Diabetic Foot Ulceration (DFU) is the most common complication, with over 60,000 people having an ulcer at any time, costing the NHS £650m annually. 40% of patients reulcerate within 1 year and 60% within 3 years. In the UK this results in 7,300 amputations per year, 20 every day. Patients who have achieved wound closure are generally in remission rather than healed. NICE recommends monthly monitoring of high-risk patients with those at the highest risk (pre/post-ulceration) monitored weekly. We propose a new system to reduce costs significantly by enabling at-risk patients to monitor their feet at home, sharing data remotely with their clinician.
Our objective is to establish proof of concept for a first-of-a-kind, non-invasive imaging system for the diabetic foot designed to assess tissue viability, monitor healing and predict the likelihood of ulceration. Imaging PPG (IPPG) is an emerging, non-contact method that can detect heart-generated pulse waves by means of peripheral blood perfusion measurements. It can capture spatial information from multiple sites simultaneously, enabling the derivation and mapping of physiological parameters. The project will develop a novel 3D-IPPG system that illuminates the foot with a specific wavelength, measuring light reflectance over a short time period with a high-sensitivity camera. This will create an image of blood flow and soft tissue perfusion in the foot which we will combine with 3D surface data to improve robustness and visualisation. It has many other applications including monitoring of pressure ulcers, burns, dermatology, reconstructive surgery and other trauma.
Proof of concept has been established and this first stage of development is due to complete in August 2019.