Review of the Capacity to Accurately Detect the Temperature of Human Skin Tissue Using the Microwave Radiation Method.

Microwave radiometry (MWR) is instrumental in detecting thermal variations in skin tissue before anatomical changes occur, proving particularly beneficial in the early diagnosis of cancer and inflammation. This study concisely traces the evolution of microwave radiometers within the medical sector. By analyzing a plethora of pertinent studies and contrasting their strengths, weaknesses, and performance metrics, this research identifies the primary factors limiting temperature measurement accuracy. The review establishes the critical technologies necessary to overcome these limitations, examines the current state and prospective advancements of each technology, and proposes comprehensive implementation strategies. The discussion elucidates that the precise measurement of human surface and subcutaneous tissue temperatures using an MWR system is a complex challenge, necessitating an integration of antenna directionality for temperature measurement, radiometer error correction, hardware configuration, and the calibration and precision of a multilayer tissue forward and inversion method. This study delves into the pivotal technologies for non-invasive human tissue temperature monitoring in the microwave frequency range, offering an effective approach for the precise assessment of human epidermal and subcutaneous temperatures, and develops a non-contact microwave protocol for gauging subcutaneous tissue temperature distribution. It is anticipated that mass-produced measurement systems will deliver substantial economic and societal benefits.

Ultrasound therapy reduces persistent post-thoracotomy tactile allodynia and spinal substance P expression in rats.

BACKGROUND: Therapeutic ultrasound (TU) alleviates nerve injury-associated pain, while the molecular mechanisms are less clear. This is an investigator-initiated experimental study to evaluate the mechanisms and effects of ultrasound on prolonged post-thoracotomy pain in a rodent model. METHODS: The rats were randomly separated into four groups (n=8 per group): sham-operation (sham; group 1), thoracotomy and rib retraction (TRR; group 2), and TRR procedure followed by TU (TRR+TU-3; group 3) or TU with the ultrasound power turned off (TRR+TU-0; group 4). TU was delivered daily, beginning on postoperative day 11 (POD 11) for the next 2 weeks. Mechanical sensitivity, subcutaneous tissue temperature, and spinal substance P and interleukin-1 beta (IL-1ß) were evaluated on PODs 11 and 23. RESULTS: Group 3, which received ultrasound treatment (3 MHz; 1.0 W/cm2) for 5 min each day, demonstrated higher mechanical withdrawal thresholds when compared with the group without ultrasound intervention (group 2) or sham ultrasound (group 4). Ultrasound treatment also inhibited the upregulation of spinal substance P and IL-1ß measured from spinal cord dorsal horns extract and increased subcutaneous temperature. CONCLUSIONS: The results of this study suggest an increase in mechanical withdrawal thresholds and subcutaneous temperature, as well as a downregulation of spinal substance P and IL-1ß, in the group which received ultrasound treatment. The regulation of spinal substance P and IL-1ß may mediate potential effects of this non-invasive treatment.