Noninvasive Temperature Monitoring Hyperthermia With Size-Adjustable Ring Array

Hyperthermia therapy is a promising treatment approach for different tumors (e.g., extremity tumors, breast tumors), yet current systems lack a reliable non-invasive temperature monitoring method, hindering widespread clinical adoption. There is a definite relationship between the speed of sound (SOS) and the temperature of human tissues, which makes SOS imaging a suitable approach for non-invasive temperature monitoring in hyperthermia. We developed a preclinical system prototype for the SOS-based temperature monitoring method. The core device of the system is a size-adjustable ring array ultrasound transducer that integrates three critical functionalities: tumor localization via ultrasound reflection imaging, focused ultrasound heating with electronic focusing, and SOS-based temperature monitoring. By integrating imaging, heating, and temperature monitoring into a single acoustic platform, the system reduces alignment errors associated with multi-device systems and improves clinical efficiency. The ring array can be quickly adapted to different hyperthermia targets (radius from 65 mm to 105 mm) with a non-iterative calibration algorithm, enhancing clinical practicality.Ex vivoexperiments demonstrate that the system enables reliable temperature monitoring while performing hyperthermia. Our all-acoustic hyperthermia system might address key challenges in temperature monitoring reliability, hyperthermia adaptability, and clinical workflow integration. This study validates a prototype system that successfully integrates SOS-based temperature monitoring with focused ultrasound heating via a size-adjustable ring array. The study establishes a basis for further technological refinement and may inform future research aimed at eventual clinical translation.