新型内冷微波天线消融肝组织的实验研究——凝固灶短轴径与功率的关系

目的 探讨微波消融肝组织凝固灶短轴径(SD)与微波功率的关系.方法 应用新型内冷微波天线,取10 min和20 min两个时间段与不同功率条件组合,凝固离体猪肝和活体狗肝,完成后分别测量凝固灶的SD和长轴径(LD),比较相同时间与功率条件下离体猪肝与活体狗肝消融灶SD、LD和SD/LD(其值越接近1.0凝固灶形念越接近球形),并分析SD与功率的关系.结果 相同条件下,活体狗肝凝同灶SD和LD均较离体猪肝小(P<0.01);而SD/LD值的差异无统计学意义(P>0.05).同离体肝相似,活体肝凝固灶SD与功率的关系表现为高度近似的线性关系(r界于0.96～0.99之间,P<0.01),其线性拟合方程截距减小,斜率增大.结论 离体肝和活体肝组织的微波凝固灶SD大小在一定条件下与功率呈高度近似的正线性关系.

Experimental study of microwave ablation in ex vivo and in vivo livers using a new type of internally cooled microwave antenna: relationship between short-axis diameter of coagulation necrosis and microwave power

Objective To probe the correlation between the short-axis diameter(SD) of coagulation necosis and the microwave power(P) using a new type of internally cooled microwave antenna in ex vivo and in vivo liver model.Methods Fourteen microwave ablations were performed in swine livers ex vivo and canine livers in vivo under the microwave powers of 30-90W and the durations of 10 min and 20 min, respectively.The short-axis diameter(SD) and the long-axis diameter(LD) of the coagulation were measured.The difference of SD, LD and SD/LD in swine liver ex vivo and canine liver in vivo were compared.The relationship between the SD and microwave power was analysised using linear regression model.Results Under the same conditions,the SDs and LDs of the coagulations of canine livers in vivo were smaller than those of swine livers in ex vivo (P <0.01).There was such a higher linear relationship(r = 0.96-0.99, P <0.01) between the SD of coagulation and the power in vivo liver model as the results acquired in ex vivo.Conclusions Although the blood flow decreased the SDs of the coagulation of microwave ablation in liver in vivo, but there was still a higher linear relationship between SD and microwave power.