Thermographic evaluation of experimental pleurisy induced by carrageenan and modified by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

The use of a thermal imaging camera may improve the detection of changes during inflammation process propagation in animals and humans that could be caused by numerous factors like 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were randomised and divided into two groups, C group, in which experimental pleural inflammatory reaction was evoked and TCDD group, in which a single dose was applied 21 days before administration of 1% carrageenan solution. Infrared thermograms were taken with a microbolometer thermal imaging camera MobIR M8. The surface temperature distribution was measured in three randomly selected animals. In the analysis of correlation we found negative results between both groups. In the C group, the pleurisy was developed and allowed to develop freely. It can be observed that both the average maximum temperature and the average minimum temperature were the highest after 48 hours after injection of the 1% carrageenan in solution. In TCDD group, lowered temperature in all days of experiments was noted. However, the increase of temperature after carrageenan injection was similar. The main changes observed in the lungs were oedema, hyperemia with clot formation and changes in lung structure. Several proliferative changes in the lungs were noted. Moreover, increased number of goblet cells as well and increased release of the surfactant was observed. The activation of fibroblasts and synthesis of collagen fibers was noted. The TCDD administration results in the reduction of superficial temperature, which is easily detectable by thermal imaging camera that can be effectively used in monitoring the course of inflammation.