Thermal imaging for detecting temperature changes within the rheumatoid foot

Abstract

The study reports the development of a thermal imaging method suitable for the screening and differentiation of joint inflammation in the rheumatoid foot of patients in comparison with the control group of healthy participants. The study included 81 patients, with rheumatoid arthritis (RA), and 39 healthy volunteers without any signs or symptoms of inflammation. The feet joints were examined by ultrasonography, and the surface temperature of the dorsal side of the foot was measured using a thermovision camera. Significant differences in mean temperatures between the study group and the control group were found. At the same time, there were no statistically significant differences between the mean temperatures in the left and right foot in any of the designated regions in the study and control group. The comparison of average temperatures of joints with or without inflammation, according to ultrasonography, did not show significance except for two joints. Despite the lack of statistical differences in the recorded temperatures, changes in the form of spikes, hot spots, and gradation of the temperatures during screening were observed. Screening analysis of the temperature distribution of the foot can aid in the diagnosis of RA and in the evaluation of the development of the disease. Additional studies must be conducted to confirm the results of this study.

Thermal characteristics of rheumatoid feet in remission: Baseline data

“…Local inflammatory processes affect superficial dermal microcirculation [9] which may be detectable by thermography, making this imaging technique particularly suited as a potential screening tool to detect any changes in skin temperature cause by vascular changes located in the superficial layers of the skin [7].…”

“…However, the use of thermography in RA has not been explored sufficiently and the available literature is still conflicting and sometimes contradictory [1,[8][9][10], resulting in inconclusive results [9]. This has precluded the application of this technology to be utilized in this field, as opposed to other fields in which today this technology is gaining in importance [3,11].…”

“…These results concur with Gatt et al [ 11 ], who explored joints of the hands and fingers of RA subjects without inflammation and have thus likewise set a baseline for normative RA thermal characteristics of the hands. A recent paper has also found significant differences in the temperature of feet between RA participants with inflammation and healthy participants, however it should be noted that their methodology differed somewhat to this study in that they analyzed temperatures through a dorsal approach [ 9 ].…”

“…Likewise Frize et al [ 1 ] conducted a study in 13 RA patients and concluded that it is possible to detect RA using IR imaging. Gizińska an co-authors [ 9 ] found significant temperature differences between RA patients and healthy controls and no significant differences between feet. In contrast, Jones et al (2018) [ 10 ], performed a cross-sectional study of the hand joints of 49 RA patients and found no statistically significant relationship between joint temperature and clinical assessment of disease activity including the Health Assessment Questionnaire.…”

Refinement and validation of infrared thermal imaging (IRT): a non-invasive technique to measure disease activity in a mouse model of rheumatoid arthritis

“…In clinical practice, IRT has been investigated and employed as a straightforward and cost-effective alternative to conventional imaging modalities for assessment of arthritis [16,17], whereas in preclinical research, particularly for small rodents like rats and mice, IRT has been used for remote welfare assessment including heart activity, respiration, motion, wound analysis [18][19][20], as well as ocular surface temperature [21].…”