蛋清热变过程中的光学特性变化

目的为解决手术中激光切割能力下降的问题，以鸡蛋蛋清为样本，研究热变过程中生物组织的光学特性变化。方法使用积分球系统测量650nm激光照射下的样本在热风枪加热下，从26％升温到99℃过程中的准直透射光、漫透射光和反射光光强随温度变化的数据，计算吸收系数和散射系数变化曲线。结果样本热变前光学特性受温度影响较小，热变过程中透射率降低，吸收系数和散射系数增大。结论手术中低强度激光照射组织发生热变使吸收能力下降，应保持较高激光强度以达到消融阈值。

Changes in the optical properties of albumen in thermal denaturation

Objective To solve the capacity decrease problem of laser cutting in surgery, changes in the optical properties of biological tissues during thermal denaturation were studied by using albumen as samples. Methods The integrating-sphere system measured the intensity changes of collimated transmitted light, diffuse transmitted light and reflected light as the samples were heated from 26~C to 99~C by a hot air gun at 650 nm laser irradiation. The curves of absorption coefficient and scattering coefficient were calculated. Results The temperature＇ s effect on optical properties of samples was small before thermal denaturation. And during thermal denaturation, transmittance decreased while absorption and scattering coefficients increased. Conclusions Thermal denaturation of tissues at low intensity laser irradiation caused absorbency decreased. Therefore, the laser should be maintained at a high intensity to reach the ablation threshold in surgery.