扩展经皮微波凝固肝组织范围的实验研究

目的：探索扩展经皮微波凝固肝组织范围的有效途径，提高较大肝癌的根治率，并减少穿刺次数。方法：用自行研制的HM－WIA型微波治疗仪对离体新鲜猪肝及活体实验兔、猪肝行微波凝固，观察天线长度、微波功率、时间、组织血流对凝固范围及形态的影响。结果：运用改进的单微波电极、中强度微波功率（45－55W）对离体、活体缺血组织行长时间（15－19min)凝固，最大凝固短径分别达5.6cm、5.3cm，凝固体积达文献的3倍；实验发现天线长36mm时凝固形态最佳；活体组织缺血凝固体积为正常供血凝固时的2.8倍（P＜0．05）。结论：采取“缺血后微波凝固策略”，运用改进的微波电极、中强度微波功率、长时间凝固有效地扩大了凝固范围，这将有利于提高肝癌尤其大肝癌的疗效，并明显减少穿刺次数。

Experimental study on expanding the space of microwave coagulation in liver

Objective To explore ways for expanding the now-limited coagulation volume of percutaneous microwave coagulation therapy(PMCT) in liver in order to enhance the complete necrosis rate of large hepatic tumors with obviously fewer punctures. Methods Fresh pig livers in vitro and rabbit, pig livers in vivo with and without blood supply were coagulated using the self-designed HM-WIA microwave coagulator to make clear antenna length, microwave power, coagulation time and blood flow influence the microwave volume(MCV).Results The device enlarged the MCV by 3 times using single electrode with an antenna of 36 mm in length along with microwave power of 45-55 W and coagulation time of 15-19 min,the short axis of the coagulation area was 5.6 cm in vitro, 5.3 cm in vivo with no blood supply.The antenna 36 mm in length was proved the best in keeping the finest coagulation shape.The MCV was 2.8 times as large without blood supply as with it (P < 0.05 ).Conclusions Innovated antenna, moderate power along with long coagulation time, ischemia tissue are key aspects leading to obviously larger MCV, which,as a result, directly reduces puncture times, meets the badly-needed effective therapy for relatively larger cancer. The strategy of making tissue ischemia before PMCT should be adopted in considering the significant influence of blood flow when large tumors are treated.