Non-contact monitoring of blood flow to the legs of people with diabetes (HeMo)

Use of off-the-shelf electro-resistive bands (non-contact sensors) and amplifier technology to monitor small hemodynamic changes in the lower limb due to arterial pulsation, which can be applicable to detect peripheral arterial disease (PAD) or chronic venous insufficiency (CVI) in people with diabetes. The device (HeMo) is a fabric cuff worn on the lower leg, incorporating two contactless stretchable electro-resistive bands which will not be in contact with the skin. The bands do not apply any substantial pressure to the user. They fit snugly, but are elastic and by design, expand with the limb during inhalation for example. The technology is largely comprised of off-the-shelf components and is battery powered. Participants will be recruited if they consent for a one-off review and examination when they are referred for the standard of care investigations for either PAD or CVI. The complete duration a participant will be required to be present is approximately 1 hour and 15 minutes, dependant on the duration of time that the validated standard of care measures of PAD and CVI take to perform. These tests are performed while the patient is supine or prone on a medical examination bed. The device will be applied for a period of approximately 15 minutes, by either a technician who has designed the device, or an experienced sonographer. During these 15 minutes the participant will have the HeMo device on their lower leg, and will remain still for one minute while the device records the blood flow at rest. The participant then moves their foot up and down 10 times, at a rate demonstrated by the investigators. The participant will then remain still for 1 minute afterwards. This is repeated 3 times and takes approximately 15 minutes to complete.