Infrared thermal imaging of human skin temperature during combined simulated hemorrhage and thermal stress

Temperature-sensing textiles have been proposed for a variety of applications, including health monitoring and sports. Skin temperature ( Tsk) measurements are an important parameter in performance sports and can be used to better understand thermoregulation during exercise. Currently, most Tsk measurements are taken using skin-mounted thermistors, which can be uncomfortable to the wearer, or thermal imaging, which can be difficult to implement and analyze. This work investigates the feasibility of using textile temperature-sensing electronic yarns (E-yarns) to measure human skin temperature during sub-maximal cycling trials. E-yarns were attached to commercially available cycling suits and measurements were recorded using both the E-yarns and the skin-mounted thermistors at rest and during sub-maximal cycling. Temperature readings were compared between the two temperature-sensing methodologies to determine the viability of using the temperature-sensing E-yarns for this application. Differences in the Tsk measurements as high as 5.9℃ between the E-yarns and skin-mounted thermistors for participants at rest have been shown. This work has also identified that a build-up of sweat significantly altered the Tsk recorded by the E-yarns in some cases. Further experiments explored the effect of saline solutions (simulating sweat) on the response of the temperature-sensing E-yarns. This work has highlighted boundary conditions for taking point Tsk measurement using electronic textiles.

Download Full-text

Daily rhythm of skin temperature of women evaluated by infrared thermal imaging

Journal of Thermal Biology ◽

10.1016/j.jtherbio.2017.12.002 ◽

2018 ◽

Vol 72 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Carlos Magno Amaral Costa ◽

Danilo Gomes Moreira ◽

Manuel Sillero-Quintana ◽

Ciro José Brito ◽

Guilherme de Azambuja Pussieldi ◽

...

Keyword(s):

Skin Temperature ◽

Thermal Imaging ◽

Daily Rhythm ◽

Infrared Thermal Imaging

Download Full-text

Infrared thermal imaging monitoring on hands when performing repetitive tasks: An experimental study

PLoS ONE ◽

10.1371/journal.pone.0250733 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0250733

Author(s):

Alejandra García Becerra ◽

Jesús Everardo Olguín-Tiznado ◽

Jorge Luis García Alcaraz ◽

Claudia Camargo Wilson ◽

Blanca Rosa García-Rivera ◽

...

Keyword(s):

Skin Temperature ◽

Experimental Test ◽

Thermal Imaging ◽

Initial Temperature ◽

Telecommunications Industry ◽

Repetitive Work ◽

Infrared Thermal Imaging ◽

Repetitive Tasks ◽

Risk Of Injury ◽

Infrared Thermal Images

The monitoring of infrared thermal images is reported to analyze changes in skin temperature in the hand fingers when repetitive work is performed to know which finger has a greater risk of injury, besides, the recovery time is analyzed regarding the initial temperature and its relationship with age, sex, weight, height if practice sports, and Body Mass Index (BMI) per individual. For the above, an experimental test was carried out for 10 minutes on a repetitive operation that takes place in the telecommunications industry and 39 subjects participated in which an infrared thermal image of the dorsal and palmar part of both hands was taken in periods of 5 minutes after the 10-minute test has elapsed. The results show that none of the participants recovered their initial temperature after 10 minutes of the experimental test. In addition, it was found that there is a relationship between skin temperature and sex, and that age influences the recovery of temperature. On the other hand, the thumb, index, and middle fingers have a higher risk of injury in the analyzed task. It is concluded that performing repetitive work with all the fingers of the hand does not show that all they have the same risk of injury, besides that, not all the variables studied affect the recovery of temperature and its behavior.

Download Full-text

The effect of constitutive pigmentation on the measured emissivity of human skin

PLoS ONE ◽

10.1371/journal.pone.0241843 ◽

2020 ◽

Vol 15 (11) ◽

pp. e0241843

Author(s):

Matthew Charlton ◽

Sophie A. Stanley ◽

Zoë Whitman ◽

Victoria Wenn ◽

Timothy J. Coats ◽

...

Keyword(s):

Body Temperature ◽

Skin Temperature ◽

Human Skin ◽

Thermal Imaging ◽

Infrared Imaging ◽

Skin Pigmentation ◽

Thermal Infrared ◽

Reflectance Spectrophotometry ◽

Thermal Infrared Imaging ◽

Thermal Emissivity

Background The measurement of body temperature has become commonplace in the current COVID-19 pandemic. Body temperature can be measured using thermal infrared imaging, a safe, non-contact method that relies on the emissivity of the skin being known to provide accurate readings. Skin pigmentation affects the absorption of visible light and enables us to see variations in skin colour. Pigmentation may also affect the absorption of infrared radiation and thus affect thermal imaging. Human skin has an accepted emissivity of 0.98 but the effect of different skin pigmentation on this value is not known. In this study, we investigated the influence of different skin pigmentation on thermal emissivity in 65 adult volunteers. Methods A reference object of known emissivity (electrical tape) was applied to participant’s skin on the inner upper arm. Tape and arm were imaged simultaneously using a thermal infrared camera. The emissivity was set on the camera to the known value for electrical tape. The emissivity was altered manually until the skin temperature using thermal imaging software was equal to the initial tape temperature. This provided the calculated emissivity value of the skin. Participants were grouped according to skin pigmentation, quantified using the Fitzpatrick skin phototyping scale and reflectance spectrophotometry. Differences in emissivity values between skin pigmentation groups were assessed by one-way ANOVA. Results The mean calculated emissivity for the 65 participants was 0.972 (range 0.96–0.99). No significant differences in emissivity were observed between participants when grouped by skin pigmentation according to the Fitzpatrick scale (p = 0.859) or reflectance spectrophotometry (p = 0.346). Conclusion These data suggest that skin pigmentation does not affect thermal emissivity measurement of skin temperature using thermal infrared imaging. This study will aid further research into the application of thermal infrared imaging as a screening or bedside diagnostic tool in clinical practice.

Download Full-text

Detection of Atherosclerosis Through Mapping Skin Temperature Variation Caused by Carotid Atherosclerosis Plaques

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4004109 ◽

2011 ◽

Vol 3 (3) ◽

Cited By ~ 7

Author(s):

Yang Yang ◽

Jing Liu

Keyword(s):

Surface Temperature ◽

Skin Temperature ◽

Thermal Imaging ◽

Infrared Imaging ◽

Imaging System ◽

Human Subjects ◽

Far Infrared ◽

Skin Surface ◽

Skin Surface Temperature ◽

Infrared Thermal Imaging

This paper reports the effects of atherosclerosis plaque on the human cervicum skin surface temperature. The classical Pennes bioheat equation and a 3-D model consisting of cervical vertebra, muscle, and skin layer is adopted to characterize the heat transfer in the cervicum. Since the formation of atherosclerotic plaque is random, several parametric analyses are conducted to simulate actual situations. A medical far-infrared thermal imaging system is employed on two healthy human subjects to evaluate the feasibility of this technique. According to the simulations, there are variations in the temperature contours on the surface of the skin due to the axial variations in thermal parameters between healthy arterial intimae and atherosclerosis plaque. This suggests that far-infrared thermal imaging can be used to detect the marker safely via a noncontact way. Additional parametric studies indicated that the cervicum skin surface temperature distribution discloses the information regarding the plaque such as position, depth, pattern, quantity, and metabolic heat generation, etc. Furthermore, the external thermal conditions and calm physiological state can be implemented to enhance the detection of the plaque via mapping skin temperature. To test this strategy, a far-infrared imaging system was applied to record the dynamic thermal pictures on the cervicum of two human subjects, and the intentional cooling by the alcohol was proposed to improve detection. The thermograph reveals the surface effects of the main blood vessel and organs in the cervicum. The present study sets up a theoretical foundation for using noncontact far-infrared imaging method for a reliable assessment of atherosclerosis plaque without causing any wound or radiation to human body.

Download Full-text