Animal Experimental Study Of High Frequency Irreversible Electroporation Ablation

ObjectiveHigh Frequency Irreversible Electroporation has a frequency of up to 500KHZ and produces alternating polarity pulses between 250 ns and 5?s,which greatly reduces muscle contraction.However,the study of H-FIRE ablation is still in the experimental stage,and its ablation range,thermal damage,and effective dose are not clear.In this paper,the second-generation high-voltage steep pulse therapy instrument independently developed by Interlligent Company is used to release high-frequency and two-way electrical pulses.The ablation effect of bipolar high-frequency irreversible electroporation with different parameters is compared through animal experiments to determine the ablation parameters.To verify the safety and effectiveness of high-frequency irreversible electroporation for ablation of dog prostate tissue.Methods1.High-frequency irreversible electroporation with different doses and different pulse widths was used to ablate rabbit liver tissue,and were sacrificed at 1 day,3 days,and 7 days after surgery.The software Image Pro was used to measure the area of the ablation zone and determine the influencing factors of the H-FIRE ablation area.The HE-staining was used to analyze whether the H-FIRE ablation effects of several different protocols were consistent.2.H-FIRE ablate the normal liver tissue of Bama pigs using an asymmetric pulse discharge method with a pulse width of 3-2-2-3?s.2800 pulses and 5600 pulses were released,respectively,and the ablation effects of these two pulse numbers on pig liver were analyzed.3.Ablation of rabbit liver tumors with H-FIRE,with parameters of 1.0 cm exposure and 1.5 cm electrode spacing.Each experimental animal used 3500 pulses with a voltage of 3000 v and a pulse width of 3-2-2-3?s.Tumor pathological changes were observed by HE staining of tissues.4.Under ultrasound guidance,the prostate tissue of Beagle dogs was ablated using H-FIRE.The parameters were set to 1.0 cm exposure and 1.5 cm electrode spacing.Each experimental animal used 3500 voltages of 3000 v and pulse widths of 3-2-2-3?s pulse.The blood and tissue changes were analyzed by analyzing blood,tissue gross observation,histopathological observation and transmission electron microscopy to analyze the bipolar high-frequency irreversible electroporation ablation of dog prostate tissue 1 day,3 days,7 days,14 days,21 days.Results1.When H-FIRE ablate liver tissue.At lower doses,the larger the dose,the larger the ablation area,but after a certain dose,the ablation area is not affected by the dose.The pulse width is symmetrical for 2?s and symmetrical for 5?s.There is no significant difference in the ablation area of the liver when the asymmetry is3-2-2-3?s,but the ablation area with asymmetrical pulse width of 3-2-2-3?s is closer to the circle.2.Asymmetric high-frequency irreversible electroporation is used to ablate liver tissue,releasing 2800 pulses does not form a continuous ablation zone,and releasing5600 pulses can form a continuous ablation zone.When H-FIRE ablate liver tissue,the closer to the tip of the needle,the stronger the degree of cell necrosis.3.H-FIRE ablation of tumors can cause tumor cells to be necrotic and the ablation boundary is clear.4.When asymmetrical high frequency irreversible electroporation was used to ablate prostate tissue,all animals did not die and no serious complications occurred.The use of high-frequency irreversible electroporation to ablate the prostate tissue of the dog will cause an inflammatory reaction,and has no effect on liver and kidney function.Through observation of pathology and ultrastructure,it was found that when high-frequency irreversible electroporation ablated prostate tissue,the cell membrane was destroyed,the cells continued to die and the large blood vessels and urethra in the ablation area were not damaged.ConclusionWhen high-frequency two-way irreversible electroporation is used to ablate tissue,a dose of 28000 V ~2/s-46000 V ~2/s is selected to ensure an effective ablation zone and tissue necrosis.Asymmetry of pulse width in 3-2-2-3?s is ablated.The area tends to be more round.When using a 3-2-2-3?s pulse,the number of pulses should be greater than 2800 and less than 5600.The degree of cell necrosis is related to the distance from the tip of the needle.The closer the distance,the more severe the cell necrosis.It is safe and feasible to ablate prostate tissue with high-frequency two-way irreversible electroporation with asymmetric pulse width.