不同参数Nd:YAG激光对椎间盘髓核组织消融能力的实验研究

Comparison of the ablation ability of the Nd:YAG laser to nucleus pulposus between different parameters

中文关键词:  经皮激光椎间盘减压术  激光参数  髓核  消融能力  山羊

英文关键词:Percutaneous laser disc decompression  Laser parameters  Nucleus pulposus  Ablation potency  Goat

中文摘要:

  【摘要】 目的：比较不同参数Nd：YAG激光（1064nm）对髓核组织的消融能力。方法：新鲜山羊腰椎标本制作成脊柱功能单位144个，随机分为18组，每组8个。前9组采用间断发射激光行髓核消融术（A方法），消融总能量和脉冲频率分别为250J/10Hz（A1组）、250J/20Hz（A2组）、250J/30Hz（A3组），500J/10Hz（A4组）、500J/20Hz（A5组）、500J/30Hz（A6组），750J/10Hz（A7组）、750J/20Hz（A8组）、750J/30Hz（A9组）；后9组采用连续发射激光行髓核消融术（B方法），消融总能量和脉冲频率分别与A方法各组对应。采用1064nm Nd：YAG激光，脉宽0.4ms，激光发射功率为10W。A方法激光每次发射持续时间1s，再次重复发射的间歇时间1s。测量消融前后标本的质量，并用游标卡尺测量汽化腔大小。结果：A方法在相同总能量条件下，脉冲频率20Hz时，消融量及汽化腔长、宽轴大于10Hz与30Hz组；脉冲频率相同条件下，能量750J时的消融量和汽化腔长、宽轴大于250J与500J组；频率与能量无交互作用。B方法在脉冲频率相同条件，能量750J时的消融量和汽化腔宽轴均大于250J与500J组，频率与能量无交互作用；频率20Hz、能量750J时，汽化腔长轴最大。相同参数激光消融量除750J/30Hz时B方法大于A方法，其余各组两种方法均无统计学差异；汽化腔长轴250J/30Hz、750J/20Hz、750J/30Hz时两种方法比较无统计学差异，其余各组汽化腔长轴B方法均大于A方法；汽化腔宽轴500J/10Hz、500J/30Hz时B方法大于A方法，其余各组两种方法比较无统计学差异。结论：相同参数下，Nd：YAG激光发射方式影响激光对山羊髓核的消融量及汽化腔形态。相同发射方式下改变激光参数可影响激光的消融能力，相同能量下，激光脉冲频率影响激光的消融能力；相同脉冲频率下，激光能量越大消融能力越强。

英文摘要:

  【Abstract】 Objective：To compare the laser ablation ability of the Nd:YAG laser（1064nm） to the nucleus pulposus between different parameters.Method：Fresh goat spines were selected to make 144 function units of the spine.The specimens were divided into 18 groups on random，8 specimens in each group.The laser was emitted intermittent in the former 9 groups（method A）.The total energy and the frequency was 250J/10Hz（group A1），250J/20Hz（group A2），250J/30Hz（group A3），500J/10Hz（group A4），500J/20Hz（group A5），500J/30Hz（group A6），750J/10Hz（group A7），750J/20Hz（group A8），750J/30Hz（group A9） respectively.The laser was emitted continuous in the latter 9 groups（method B）.The total energy and the frequency of each group was corresponding to method A.The intervertebral discs were radiated by Nd:YAG laser，the pulse width was 0.4ms，the power in each group was 10W.The laser was emitted lasting for 1s，and the interval time was 1s in group A.There was no interval time in group B.The weight of the specimen was measured before and after ablation，and the cavities were measured after radiating by sliding caliper after ablation.Result：At the same energy of method A，when the frequency was 20Hz，the ablated quantity and the long and wide axis of the cavity all exceeded 10Hz and 30Hz.At the same frequency，when the energy was 750J，the ablated quantity and the long and wide axis of the cavity all exceeded 250J and 500J.There was no interaction between frequency and energy.At the same frequency of method B，when the energy was 750J，the ablated quantity and wide axis of the cavity all exceeded 250J and 500J.There was no interaction between frequency and energy.When the energy was 750J and the frequency was 20Hz，the long axis of the cavity was largest.At the same parameter，the ablated quantity was greater in method B than method A when the parameter was 750J/30Hz，and the remaining groups were not statistically significant between the two methods.The long axis of the cavity was greater in method B than method A except when the parameters were 250J/30Hz，750J/20Hz and 750J/30Hz.The wide axis of the cavity was greater in the method B than method A when the parameters were 500J/10Hz and 500J/30Hz，and there was no statistically significant difference in the remaining groups between two methods.Conclusion：At the same parameter，both the quantity of ablation and the form of cavity are influenced by the mode of laser.The ablation ability is influenced by the different modes of the Nd:YAG laser when the parameter is changed.At the same energy，the ablation ability is influenced by the frequency of laser；at the same frequency，the ablation ability enhances with the increase of energy of laser.