Diabetic Foot Ulcers: The Clinical Problem
Studies have shown1, 2 that prior to the development of a foot ulcer, skin temperature is elevated at potential ulceration sites. The importance of rigorous foot temperature monitoring to identify the early signs of ulceration has been emphasised in many clinical studies and forms the basis for diagnostic guidelines around the world, as an approach to identify the early warning signs and implement prevention strategies.
However, the temperature measurement techniques currently used are slow and subjective. Multiple temperature readings of each foot must be taken and compared by a trained clinician. On average this process can take more than 10 minutes per patient, making it an impractical approach for more frequent patient checks or widespread use with the diabetic population. Also, this technique is only used on the sole of the foot, where just 40% of ulcers occur, resulting in the thousands of potential ulcers being missed by clinicians each year.
In addition, the imprecision of current practice introduces the risk of subjectivity and variations in diagnosis. Thermal imaging offers a potential alternative diagnostic method, but to date has suffered from a measurement uncertainty of ±2ºC. This temperature measurement inaccuracy is too great to be of any diagnostic value which is why the diagnostic potential of thermal imaging has not been exploited to date.
Celsius Health’s proprietary technology addresses this issue by reducing the temperature measurement uncertainty ten-fold to ±0.2ºC, all while capturing and comparing tens of thousands of temperature points instantly. This offers, for the first time, a practical application of thermal imaging for the detection of potential ulceration in diabetic patients.
The benefits of Celsius Health’s technology include:
- Function: Our device scans the entire surface of both feet, not just the plantar region, where only 40% of ulcers occur, increasing the chance of finding potential ulcers earlier
- Speed: The process takes seconds and maps temperatures to the foot surface while automatically displays the temperature.
- Objective and image based data: Our device is able to give rigorous measurement data to allow easier referral as well as giving patients an image to demonstrate what is happening to their feet and why they need to follow a specific intervention. This can assist in driving both patient education and behavioural change.
The only tools that currently address this are single point thermometers, which have the limitations identified above and as a result are not always used routinely by podiatrists.
The first Celsius Health thermal imaging devices have been extensively tested in clinical trials conducted at Kings College Hospital London, Freemans Hospital, Newcastle upon Tyne and the Pennine Acute Hospital Trust. The results obtained from these trials demonstrate the accuracy of this technology in assessing diabetic feet in a clinical situation – click here to view research.
1 Lavery L et al, Diabetes Care, 2004
2 Lavery L et al, Diabetes Care, 2007