Thermal Imaging Improves Diabetes-Related Ulcer Assessment

A new suggests that textural analysis of thermal images of venous leg ulcers (VLUs) can detect whether a wound will need extra management.

Researchers at RMIT University (RMIT; Melbourne, Australia) and the Bolton Clarke Research Institute (Melbourne, Australia) conducted a study involving 60 patients with 72 VLUs who were followed over a period of twelve weeks. Digital and thermal images, as well as planimetry wound tracings were recorded, with the weekly change in thermal textural features computed. VLU’s were labelled as healed or unhealed based on status of the wound at 12th week follow up.

The results showed that principal component analysis (PCA) of the change in textural features in the second week (compared to week 0) were statistically significant predicting which VLA will not heal by week 12. According to the researchers, this is because wounds change significantly over their healing trajectory, with higher temperatures signaling potential inflammation or infection, while lower temperatures indicate a slower healing rate due to decreased oxygen in the region. The study was published on June 24, 2021, in the Nature Scientific Reports.

“The significance of this work is that there is now a method for detecting wounds that do not heal in the normal trajectory by week two using a non-contact, quick, objective, and simple method,” said study co-author Rajna Ogrin, PhD, of Bolton Clarke Research Institute. “A non-contact method like thermal imaging would be ideal to use when managing wounds in the home setting to minimize physical contact, and therefore reduce infection risk.”

VLU guidelines state that if wound area has not reduced by at least 20–40% after four weeks, additional interventions are warranted. Current assessment methods to monitor wound progress over this four week period involve wound tracing and measurement, including use of digital planimetry, observation and documentation of the wound tissue type, wound edge characteristics, peri-wound and surrounding skin state, and level and type of exudate. This requires at least weekly evaluations and physical contact with the wound.

Related Links:
RMIT University
Bolton Clarke Research Institute