Juhasz T, Hu X H, Turi L, Bor Z
Intelligent Surgical Lasers, San Diego, California 92121.
Lasers Surg Med. 1994;15(1):91-8. doi: 10.1002/lsm.1900150112.
Time-resolved flash photography was used to investigate the dynamics of shock waves and cavitation bubbles generated by picosecond optical breakdown in bovine corneal tissue and water. A picosecond Nd:YLF laser was employed. A rapid decay of the shock waves was observed in both materials, with similar temporal characteristics, indicating that water serves as a good model for shock wave studies. In contrast, differences in the cavitation bubble dynamics were found between cornea and water, which are related to differences in the mechanical and thermal properties of the two media, suggesting that water should not be used to model cavitation dynamics in cornea. The experimental results also suggest that the efficiency of intrastromal ablation may be increased by using short pulses and moderate pulse energies in order to avoid the creation of large cavitation bubbles. The experiment indicates that the optimum laser repetition rate for intrastromal ablation is between 1 and 5 kHz.
采用时间分辨闪光摄影技术研究了皮秒光击穿在牛角膜组织和水中产生的冲击波和空化泡的动力学特性。使用了皮秒钕：钇锂氟激光器。在两种材料中均观察到冲击波的快速衰减，且具有相似的时间特性，这表明水是冲击波研究的良好模型。相比之下，发现角膜和水之间的空化泡动力学存在差异，这与两种介质的力学和热学性质差异有关，这表明水不应用于模拟角膜中的空化动力学。实验结果还表明，通过使用短脉冲和适度的脉冲能量可以提高基质内消融的效率，以避免产生大的空化泡。实验表明，基质内消融的最佳激光重复频率在1至5千赫兹之间。
