脉冲CO_2激光消融离体人乳突骨组织的特性

Characteristics of Pulsed CO_2 Laser Ablation on in vitro Human Mastoid Bone Tissue

目的探讨脉冲CO2激光对离体人乳突骨组织的消融阈值及热损伤。方法脉冲CO2激光功率从1 W逐渐增大到12W,频率为60 Hz,光斑直径为1.40 mm。定点照射离体人乳突骨,利用连续组织切片、光学显微镜扫描电镜等检查手段对消融弹坑形态特征及其周围热损伤深度进行测量。结果实验获得消融弹坑深度及周围热损伤深度随激光能量密度的变化关系,并确定脉冲CO2激光对离体人乳突骨组织的消融阈值为1.98～2.60 J/cm^2。结论本研究为临床提供具有参考意义的光剂量学基础数据,促进激光消融技术在耳外科领域中的应用。

Objective To investigate the ablation threshold and thermal damage of in vitro human mastoid bone tissue with pulse CO2 laser. Methods The laser power of irradiation varied from 1 W to 12 W, the pulse repetition rate was 60 Hz and the spot size on the tissue surface was 1.40 ram. Morphologic characteristics of the ablation crater were measured by use of both tissue slicing and scanning elec- tron microscopy after irradiation. Results The experiment obtained the trend of ablation crater depth and thermal damage depth along with energy density, and found the ablation threshold in the energy density. Conclusions This study provides a reference of basic light dosimetry data for clinical application, and promotes the application of the laser ablation technology in ear surgery.