The time of day affects the scrotal surface temperature measured by infrared thermography and rectal temperature in rats
Year: 2017
Type: article
Abstract: Infrared thermography is a non-invasive diagnostic method that allows to determinate by thermal mapping, the physiological state of a tissue or organ, which can contribute to a medical diagnosis. To validate infrared thermography as a research or clinical tool, it is essential to determine factors that may influence the measurement of scrotal surface temperature (SST). Some relevant factors are already stated for an accurate thermographic measure as environment temperature and humidity and the distance between the camera and the target. Thereby the aim of this study was to determinate if the time of the day interferes on SST, measured by infrared thermography and to determine the difference between SST and rectal temperature in rats. The thermographic imaging protocol was standardized to reduce interferences in the measurements creating a reliable pattern. All research was conducted in a temperature and humidity controlled room (20°C and 60% humidity). Scrotal temperature image was performed by thermographic imaging using an infrared camera (Flir®, Infra Cam TM, FLIR Systems Inc. Portland, EUA), held 60 cm from the testicles. Rectal temperature was performed using a clinical digital thermometer after the thermography measurement. Twenty-four Wistar rats were used, aging 70-days-old and weighting 242.6 ± 16.0 g. The SST and rectal temperature were measured at two times of the day (9 am and 2 pm). The images were analyzed by Flir Quick-Report 1.2 SP2 Software (2009, FLIR Systems Inc.). The SST and rectal temperatures were analyzed by R stat software 3.2.2 using Shapiro–Wilk and t test was used with 5% (p < 0.05) significance level. The results were expressed in means and standard deviation. The mean of SST and rectal temperature were lower (p < 0.001) at 9 am than at 2 pm (SST: 28.2 ± 0.7 oC and 30.8 ± 0.7 oC; rectal temperature: 36.5 ± 0.3 oC and 37.3 ±0.4 oC, respectively). Additionally, the SST is 7 to 8 °C below rectal temperature in rats. We concluded that there are interference of the time of the day on SST and rectal temperature in rats, making necessary to standardize the time of the day to use infrared thermography tool to research. (CEUA- FMVZ – UNESP, Botucatu protocol 46/206).
Source: Animal Reproduction
Institution: Universidade Estadual Paulista (Unesp)
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $450
OpenAlex ID: W2598591945