Tumor Ablation Temperature Monitoring System Based On Fiber Grating

With the development of medical pulsed electric field ablation technology,the instantaneous power of pulses is getting larger,and the need for temperature monitoring and feedback of ablation process in tumor treatment is getting stronger.The temperature monitoring of the ablation has played a escort role in the entire tumor treatment.However,under high power fields,not only high-intensity electromagnetic interference,but also complex chemical and biological reactions exist.The original electronic temperature sensors have certain limitations and do not meet the development of tumor treatment technology requirements.The optical fiber temperature measurement can avoid electromagnetic interference,it has a good prospect in the clinical application of tumor ablation.This paper mainly studies the temperature monitoring system of tumor ablation based on fiber grating,combined with the filtering process and the method of extracting the characteristic frequency,to obtain the online monitoring of the temperature during tumor ablation and the rabbit breathing rate and heart rate.According to the characteristics of optical fiber sensor,a temperature monitoring system based on fiber grating for tumor ablation with pulsed electric field is proposed.The temperature,space and time resolution of the system can reach 0.1?,2.5 mm and 1 ms,respectively.This system has the characteristics of simple system and good integration,which is obviously superior to other tumor temperature monitoring methods.In this paper,this system is used to obtain the online temperature of the tumor during ablation under microsecond and nanosecond pulse electric fields.The microsecond pulse therapy liver temperature rise not exceeding 3?,nanosecond pulse therapy temperature rise not exceeding 6?.It was concluded that pulsed electric field therapy could not provide enough heat to heat the treated tissues,which ruled out the effect of overheating.The difference in temperature distribution between the two pulse input methods is compared,and the conclusion is obtained that the heat of the single electrode is concentrated around the electrode and the heat of the double electrode is concentrated between the electrodes.In this paper,the filtering process and frequency extraction method are used to obtain the rabbit's breathing and heart rate during ablation.Finally,based on the electric field heat and biological heat transfer equations,the electric and biological heat transfer coupling models are established,and the simulation calculation is carried out in combination with the finite element method.The simulation results prove the feasibility and accuracy of the temperature monitoring system.The tumor temperature monitoring system based on fiber grating provides a new temperature monitoring method for tumor ablation therapy,and it can also be applied to temperature monitoring of other medical process in the future.