Cilesiz I, Springer T, Thomsen S, Welch A J
Biomedical Engineering Program, University of Texas, Austin 78712-1084, USA.
Lasers Surg Med. 1996;18(4):325-34. doi: 10.1002/(SICI)1096-9101(1996)18:4<325::AID-LSM1>3.0.CO;2-U.
Thermal denaturation of proteins is recognized as a rate process governed by the local temperature-time response and is believed to be the principal mechanism for photothermal tissue welding. Since rate processes are exponential with temperature, feedback control of tissue surface temperature is hypothesized to create a quasi-constant rate of denaturation that will enhance the tissue welding process.
STUDY DESIGN, MATERIALS AND METHODS: Controlled temperature tissue welding of severed edges of fresh canine jejunum was performed in vitro by remote sensing of tissue surface temperature with an infrared sensor. A hardware controlled temperature feedback system opened and closed a shutter located in the beam path of an argon ion laser to provide constant temperature welding.
Strong tissue fusion was not possible at or below a surface temperature of 70 degrees C, but was accomplished at 80 degrees, 90 degrees, and 95 degrees, and 100 degrees C. Fusion was achieved with thermal coagulation of the collagenous submucosa and mucosal tissues. The bursting strength of welds created at 90 degrees C and 95 degrees C were significantly stronger than those performed at 80 degrees C.
Laser-assisted intestinal anastomoses created in vitro are optimally strong at 90-95 degrees C feedback control temperatures.
蛋白质的热变性被认为是一个受局部温度-时间响应支配的速率过程，并且被认为是光热组织焊接的主要机制。由于速率过程随温度呈指数变化，因此假设对组织表面温度进行反馈控制可产生准恒定的变性速率，这将增强组织焊接过程。
研究设计、材料与方法：通过用红外传感器遥感组织表面温度，在体外对新鲜犬空肠的断端进行控温组织焊接。一个硬件控制的温度反馈系统打开和关闭位于氩离子激光束路径中的快门，以提供恒温焊接。
在表面温度为70摄氏度或更低时，无法实现牢固的组织融合，但在80摄氏度、90摄氏度、95摄氏度和100摄氏度时可以实现。通过胶原性黏膜下层和黏膜组织的热凝实现融合。在90摄氏度和95摄氏度下形成的焊缝的爆破强度明显高于在80摄氏度下形成的焊缝。
体外创建的激光辅助肠吻合术在90 - 95摄氏度的反馈控制温度下强度最佳。
