Thermal Cameras Detect Rheumatoid Arthritis When Symptoms Are Absent

Thermal imaging could be an effective method for assessing rheumatoid arthritis (RA), according to a study performed at Staffordshire University.

The study sought to determine whether RA patients without active inflammation in their hands exhibited different baseline thermographic patterns of the fingers and palms when compared to healthy individuals. Results of the study, carried out with 82 participants, demonstrated that both palm and finger temperature increased significantly in patients with RA.

The RA patients were recruited upon confirmed absence of synovitis by clinical examination and musculoskeletal ultrasound. The researchers used a FLIR T630 thermal camera and followed the guidelines of the American Thermology Association.

The researchers found significant differences between the mean temperatures of the palm regions and fingers of the healthy participants compared to their RA counterparts, with the RA group exhibiting higher temperatures in all regions of interest. The researchers hypothesized that this temperature difference could be caused by underlying subclinical disease activity or that the original inflammatory process could cause irreversible thermography changes that persist after the disease activity has resolved.

Although further studies are required, the research team believes that thermography could be an innovative imaging modality for detecting RA with increased sensitivity compared to other imaging modalities. “While ultrasonography had not detected any significant changes in our study population, thermography flagged a possible ongoing disease process by reporting these higher temperatures,” Alfred Gatt, from the University of Malta and a visiting fellow at Staffordshire University, said. “Thermal imaging is an emerging technology within medicine and has the potential to become an important clinical tool as disease processes can vary the magnitude and pattern of emitted heat in a person with rheumatoid arthritis.”

The research was published in Scientific Reports (www.doi.org/10.1038/s41598-019-53598-0).