Evaluation of Temperature Distributions during Ultrasonography

Background: Ultrasound has played a vital role in the medical imaging system for real‑time examination. It is considered safe and economical compared to other imaging modalities. Absorption of ultrasound energy by biological tissues can result in heating, especially if the high intensity is used for a long duration. Aim: This study aims to evaluate temperature changes in diagnostic ultrasound scanning patients undergoing different ultrasound examinations. Materials and Methods: An infrared thermometer was used to measure the temperature in the subjects’ regions of interest. The transducers of frequencies 3.5 and 7.5 MHz were used for the transmission and reception of ultrasound energy to and from the region of scanning. Three hundred and four patients were recruited from different ultrasound examinations. The thermometer was placed at a distance of 5–15 cm to record temperature changes before and during the ultrasound procedure on each of the subjects. The obtained data were statistically analyzed using the Statistical Package for the Social Sciences (SPSS) version 20. Result: The average room temperature during the scanning was 22.2°C. The mean temperature before scanning procedures was 32.3°C. The mean maximum and minimum temperatures before and during the scanning of 304 patients recruited for this study were 34.4°C and 31.3°C, respectively. There was also a significant difference between the temperature measured before and during the scanning of the patients (P = 0.01). Conclusion: The findings in this study show that temperatures during the diagnostic ultrasound scanning are not above normal human body temperature; therefore, observable thermal effects are unlikely possible.