Comparative Study On The Ablation Range And Gasification Range Of Different Tissue In Vitro By Laser,Radiofrequency And Microwave Ablations

Objective: In this study,we performed ultrasound-guided laser,radiofrequency and microwave ablation of liver and muscle in vitro,and compared the relationship between ablation range and ablation time and power;compared the difference between ablation range and gasification range of different tissues in the same ablation condition;observed the relationship between gasification range and ablation range;compared the ablation range and gasification range of three ablation methods.Methods: Under the guidance of ultrasound,the laser fiber was inserted into the tissue under the guidance of the puncture needle,the depth of the needle was about 1 / 3 of the length of the specimen,and the needle withdrawal was about 1cm.Under the pulse mode,the power of 30 W,60W and 90 W was used to ablate the liver and muscle for 30 s,60s and 90 s respectively;under the guidance of ultrasound,the radiofrequency needle was inserted into the tissue,the depth of the needle was deeper than that of the laser ablation,about 2 / 3 ～ 3 / 4 of the length of the specimen,The ablation power of 15 W,30W and45 W was selected to ablate the liver and muscle for 30 s,60s and 90 s respectively.After that,the tissue was cut along the long axis of the needle path to observe the ablation range,measure the size of each meridian and calculate its volume;the ablation power was 15 W,30W,45 W,and the ablation time was 90 s.The liver and muscle were ablated by laser,radio frequency and microwave respectively,and the ablation range and gasification range were recorded,and the three ablation methods were compared.Results: Under the same conditions,the ablation range of liver and muscle increased with the increase of power and time in a certain range(P < 0.05).When the ablation power and time reach a certain degree,the increasing trend of ablation range slows down,and the gasification range even decreases;Under the same ablation conditions,the ablation range of liver was larger than that of muscle in a certain range in laser ablation,and the ablation range of muscle was larger than that of muscle in radiofrequency ablation and microwave ablation;There was a significant correlation between the ablation range and the gasification range of liver and muscle after ablation(P < 0.01);At the same power,the ablation range of RFA was the largest,LA was the second,MWA was the smallest in liver and muscle,and the differences among the groups were statistically significant(P < 0.05).Conclusion: The size of tissue ablation range is related to ablation power,ablation time and tissue biological characteristics.There is a significant correlation between gasification range and ablation range under ultrasound observation,which can guide the clinical use of ablation therapy.