How to monitor real-time temperature using radiofrequency microwave in tumor hyperthermia

Sensor teòthachd fibre optic, Siostam sgrùdaidh tuigseach, Neach-dèanamh fibre optic air a chuairteachadh ann an Sìona

What is tumor hyperthermia

Tumor hyperthermia is the use of various heat sources such as radiofrequency electromagnetic waves, microwaves, or ultrasound to heat the tumor area to an effective therapeutic temperature range and maintain it for a period of time, causing immediate metabolic reactions in the tumor tissue, thereby causing changes in the molecular structure of tumor cells and enhancing lysosomal activity, achieving the goal of killing tumor cells and treating tumors.

Tha an fluorescence fiber optic temperature measurement system independently developed by FJINO provides temperature measurement assistance for radiofrequency hyperthermia. It can accurately measure temperature under radiofrequency electric field with an accuracy of 1 ℃ (high precision can be customized). By combining thermal field simulation of tumor tissue, it is possible to infer the overall temperature distribution of the tumor through a few measurement points. After analyzing the experimental results and processing the data, it has been verified that the tumor radiofrequency hyperthermia device can meet the design requirements and has practical applications in the medical field.

Why does tumor hyperthermia require temperature measurement

An-dràsta, all tumor extracorporeal radiofrequency hyperthermia machines on the market lack effective and feasible online monitoring methods for tumor temperature during tumor hyperthermia. Traditional electronic temperature sensors, such as thermistors, thermocouples, etc., are susceptible to electromagnetic wave interference and cannot measure temperature in real time during the heating process, making it difficult to accurately determine the temperature of the tumor site and the normal tissue temperature around the tumor, seriously affecting the effectiveness of thermal therapy.

Compared with traditional temperature sensor measurement methods, optical waves have many incomparable advantages: light waves do not cause electromagnetic interference, nor are they interfered by electromagnetic waves, and are easily perceived and received by various photosensitive detectors. It is easy to convert optical signals into electrical signals or electrical signals into optical signals, which can be well matched with modern electronic devices and computers. The working spectrum of optical fibers is wide, the dynamic range is large, and it is an excellent transmission line with low loss. Optical fibers themselves are not charged or conductive, with good insulation performance, radiation resistance, bendability, cuideam aotrom, and small volume. They can be applied in harsh environments where other types of sensors cannot meet the conditions, such as strict space limitations, flammability, explosiveness, or strong electromagnetic interference.

The working mechanism used in fluorescence temperature measurement

When a material is excited by exposure to ultraviolet, visible, or infrared light, a phenomenon of light emission is called photoluminescence. In the phenomenon of photoluminescence, the parameters of emitted fluorescence are closely related to the temperature of the environment. To obtain the required temperature information, it is only necessary to detect the intensity or lifetime of its fluorescence.

The correspondence between fluorescence lifetime and temperature of fluorescence lifetime temperature sensors does not change due to changes in light intensity, and has advantages such as self calibration, small heat capacity, and fast response speed. Tha an fluorescence fiber optic temperature measurement system can accurately measure temperature without interference under radio frequency electric fields;