Pre‐Clinical Testing of Microwave Radiometer and a Pilot Study on the Screening Inflammation of Knee Joints

Abstract

This article presents the pre‐clinical evaluation of our custom‐built, single‐band microwave radiometer centered at 1.3 GHz for deep tissue thermometry, and a pilot study on volunteers for passive detection of inflammation in knee joints. The electromagnetic (EM) compatibility of the battery‐operated radiometer for clinical use was assessed as per International Special Committee on Radio Interference (CISPR) 22 standard. The ability to detect inflammation in knee joints was assessed using a substrate integrated waveguide antenna connected to the radiometer. EM compatibility tests carried out in the laboratory indicated device immunity to intentional radiated interference up to −20 dBm injected power in the global system for mobile communication frequency band, and pre‐compliance to CISPR 22 standard. Radiometer temperature measurements recorded at the lateral and medial aspects of both knees of 41 volunteers indicated mean temperature greater than 33°C for the diseased sites compared with the mean temperature of 28°C measured for the healthy sites. One‐way analysis of variance statistics indicated significantly (P < 0.005) higher radiometer temperature at the diseased sites unlike the healthy sites. Thus, the EM pre‐compliance of the device and the potential to measure deep tissue inflammation were demonstrated. Bioelectromagnetics. 2019;40:402–411. © 2019 Bioelectromagnetics Society.

Research of a microwave radiometer for monitoring of internal temperature of biological tissues

“…A series of studies related to identification of inflamed atherosclerotic plaques and assessment of stroke risk have been carried out [4,5]. MWR is also used in non-invasive diagnosis of arthritis [6], brown fat activity [7] and examinations of brain [8,9], spine [10] and joints [11]. Interesting results were obtained in the field of phlebology [12], experimental oncology [13], gynecology [14] and urology [15,16].…”

“…. w sw a α = α + α (11) The noise signal from the heated resistor at the switch output is determined from the following equation:…”

Portable microwave radiometer for wearable devices

“… detect breast cancer and monitor the effectiveness of the administered treatment (Vesnin, Turnbull, Dixon and Goryanin, 2017;Goryanin, et al, 2020),  examine carotid arteries to reveal inflamed atherosclerotic plaques and patients with a high risk of stroke (Toutouzas, et al, 2017;Drakopoulou, et al, 2018),  measure the brain temperature (Groumpas, et al, 2019;Kublanov, Borisov, 2017;Gudkov, et al, 2019), both in treatment of stroke and traumatic brain injuries (Cheboksarov, et al, 2015),  monitor the brain temperature during hypothermia (Rodrigues, et al, 2018),  diagnose inflammatory joint diseases (Laskari, et al, 2020;Ravi, Sharma and Arunachalam, 2019),  diagnose vesicoureteral reflux in children (Arunachalam, et al, 2011;Jacobsen, Klemetsen and Birkelund, 2012),  evaluate the activity of brown adipose tissue (Crandall, et al, 2018),  assess intensity of backpain (Tarakanov and Goryanin, 2020).…”