Thermography and its applications in medical and clinical research field

The current method to diagnose Type-2 diabetes is invasive like checking blood-sugar levels and Hb1AC by giving blood sample for testing. Using thermal imaging camera, we introduce a non-invasive method, with which the mass screening of people can be carried out for early diagnostic of Type-2 diabetes. Similarly, fever detection by mass screening of people is also possible: It is a fast, easy, contactless method to screen persons to track the risk of elevated body temperatures, which in turn is an indicator of potential viral infections.

Introduction

All objects with a temperature above absolute zero emit enfrared radiation because of the thermal motion of their molecules. Infrared thermography (IRT) is an imaging modality that can be used to detect this radiation which is also called thermal radiation. Human skin emits infrared radiation almost like a perfect black body and thus IRT is well suited for the measurement of skin temperature. Not only that now thermography finds several applications in the medical field such as fever detection, identifying blood circulation disturbances, determining symptoms of diabetes, screening of joint inflammation and rheumatoid arthritis etc. This application note briefly describes some of the application areas where Testo Thermal Imagers have proved out to be an efficient tool to analyse medical conditions and syndromes in various test cases.

Case Study 1: All India Institutes of Medical Sciences (AIIMS), New Delhi — Testo 890

References

  • Anthropometric Measurement: It is the systematic measurement of size, shape and composition of the human body using relevant indices to detect changes in the nutritional situations of the body.
  • HbA1c: This refers to glycated haemoglobin and by measuring HbA1c, one can get an overall picture of what one’s average blood sugar levels have been over a period.
  • Thermography as a non-invasive method for diabetes detection: A diagnostic approach for Type 2 diabetes was conducted on the subject based on Non-Contact Infrared Thermal Imaging. Control (healthy) and diabetic group differ in discriminatory performance of various risk factors and anthropometric indices as segregated by HbA1c. A significant negative correlation of the HbA1c with the core body temperature (a function of body metabolism) was obtained through this non-invasive measurement by Testo 890 at the inner canthus of the eye, neuropathic foot and at the tympanic region of the ear.
Figure 1 Thermograph of the fascial region

Case Study 2: Pharmaceutical Industry, R&D centre

Testo 890 References

  • Vasodilation: It is the widening of blood vessels in the human body. It results from relaxation of smooth muscle cells within the vessel walls, particularly in the large veins called vasodilators, large arteries, and smaller arterioles.
Figure 2 Peripheral vasodilation

Clinical Trials on Vasodilation

The blood vessels are monitored by thermal inspection before and after taking drugs. This is generally used in clinical trials during various phases of sports medicines and Ayurveda medicines/ drug development. To facilitate clinical trials, tests were carried out to see the effect of a test substance for peripheral vasodilation. Testo infrared thermography camera, Testo 890 was used to see and indirectly measure vasodilation by means of the change in peripheral temperatures.

Case Study 3: National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru

References

  • T2DM: Diabetes mellitus type 2 (or type 2 diabetes) is a chronic condition that affects the way the body processes blood sugar and is characterised by high blood sugar, insulin resistance, and relative lack of insulin.
  • Analysis of Type 2 Diabetes: Infrared (IR) thermography imaging will be able to monitor progression & improvement of T2DM patients (with yoga-based lifestyle therapy) as compared with an invasive method of checking HbA1C, & biochemical assay of HbA1c as standard. Research is going on by using thermography camera Testo 890 to detect/diagnose the early diabetic condition by the non-invasive method by close thermal inspection of human being eyes, ear, face, palm, and foot. Also, by monitoring changes in body temperature after and during yoga.
Figure 3 Thermography of a diabetic foot.
Figure 4 Energy emitted during Yoga Therapy.

The session has been imaged using thermography which allows us to see thermal energy or radiation, more commonly referred to as heat. Thermal Infrared is found within the Infrared region on the electromagnetic spectrum. The different colors in the images represent different levels of thermal energy being emitted from the skin’s surface. In this image, the white, red, yellow and orange colors show a high level of thermal energy while the blue, black and purple show a lower level.

Customised software for Medical / Clinical Thermography

  • The software generates the thermal image with Region of Interest (ROI), pointers, date, time, distance and other parameters of importance in a text file with the patient name. The data in the text file can be used by researchers in this field for analysis and R&D.
  • We can stream the thermal and digital video at a time in LabView which cannot be otherwise done. Patient-specific report along with the image in a consolidated form is now possible. This finds applications in Medical Research Institutes and hospitals.
Figure 5 Controlled from LabView

From the details depicted in the above case studies, it is evident that Thermal Imager Testo 890 is an advantage for medical Thermography and serve various purposes.

Figure 6 Fever Detection feature
Figure 7 Testo 890

Following advantages make Testo 890 the winner for Clinical Thermography:

  • The image resolution of 640 X 480 IR pixel and 1280 X 960 with Testo Super-Resolution
  • Sequence Capturing: This helps to capture thermal images automatically with set time and number of images set. Also, with respect to the temperatures set points.
  • Radiometric video of the patients for monitoring purpose is easily possible.
  • Thermal sensitivity of 40mK helps them in accurate temperature difference within the selected shortest possible zone.
  • Fever detection feature allows you to see the face of a human body to accurately monitor and detect febrile condition through a window in thermal imager screen against the set point for the temperature with emissivity automatically set to 0.98 for human skin. Anything beyond the set point temperature will show in red color automatically.
  • Customised Software for medical/clinical thermography.

    For further details contact
    Testo India Pvt. Ltd.
    Website: www.testo.com