在电凝闭合生物组织的过程中,利用组织阻抗的变化作为反馈参数,从而控制射频能量的输出,但阻抗的变化只在当组织液沸腾,即射频能量传递的最后阶段才发生,在组织液温度较低时则变化不明显。电凝闭合时组织的脱水和变性过程其含水量会发生改变,特别在温度上升之初组织含水量会发生显著变化,因此组织含水量可作为射频输出实时反馈的一个良好参数。组织中水分对1 300 nm波段的近红外光具有很好的吸收性,所以组织中的水分含量可以通过光透射率的变化间接获得。由此可利用在射频电凝器械闭合组织时,探测组织的光透射率变化情况得到含水量变化,以此作为射频能量输出的实时反馈,达到了更安全有效闭合血管的目的。

During the electrical coagulation close of biological tissues, tissue′s impedance usually used as feedback parameters to control the RF output power, but the change in impedance only happens when the tissue fluid boiling. In other words, it happens only at the final stage of RF energy transmission. When the temperature of tissue fluid is low, the impedance does not change significantly. Dehydration and denaturation processes of the organization changes its moisture content when using electrical coagulation to close tissues, especially at the beginning of the temperature rising. The water content of tissues changes significantly, because tissue water content can be used as a good parameter for RF output in the real-time feedback. 1 300 nm wavelength of the near-infrared light is very good for tissue water′s absorbency, so light transmittance change is a fact of tissue moisture content variation. As a result, detecting the changes of light transmittance can obtain the changes of the tissue water content,and it is used as a real-time feedback parameter for the output RF energy. Using radio frequency coagulation instrument to close tissue in this way can achieve a safer and more effective closure of the vascular surgery.