Plasma formation in holmium:YAG laser lithotripsy.
Plasma formation in holmium:YAG laser lithotripsy.
复制标题
钬：YAG 激光碎石术中的等离子体形成。
DOI：
10.1002/lsm.23659
复制
发表时间：
2023
影响因子：
2.4
通讯作者：
Stoller,MarshallL
中科院分区：
文献类型：
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作者：
Pishchalnikov,YuriA;Behnke-Parks,WilliamM;Stoller,MarshallL
目标在钬：钇铝石榴石（钬：YAG）激光碎石术打破尿路结石期间，泌尿科医生经常看到闪光。由于红外激光脉冲是不可见的，那么光源是什么？在这里，我们研究了激光碎石术中闪光的起源、特征和一些影响。方法使用超高速视频显微镜记录 0.2-1.0J 能量的单激光脉冲，用 242μm 玻璃芯直径的光纤与整个手术取出的尿路结石和空气和水中的羟基磷灰石 (HA) 涂层玻璃载片接触。用水听器测量声瞬变。可见光和红外光电探测器解析了可见光发射和红外激光脉冲的时间分布。结果激光脉冲的时间分布显示出不同持续时间和幅度的强度尖峰。人们发现脉冲产生暗淡的光和明亮的火花，上升时间为亚微秒。激光脉冲开始时强度尖峰产生的火花在周围液体中产生冲击波。随后的火花处于蒸气泡中，没有产生冲击波。火花增强了激光辐射的吸收，表明等离子体形成和光学击穿。即使是同一种尿路结石，火花的出现和数量也各不相同。使用 HA 涂层载玻片，在 >0.5 J 的激光能量下始终观察到火花。载玻片因空化而破裂或破裂，并在 63±15% 的脉冲 (1.0 J,N= 60) 中产生火花。在没有火花的情况下，不会发生载玻片破裂（1.0 J，N= 500）。 结论 在之前的研究中没有意识到，自由运行的长脉冲钬：YAG 激光器形成的等离子体可以成为激光手术中的一种额外的物理作用机制。
ObjectivesDuring holmium:yttrium–aluminum–garnet (holmium:YAG) laser lithotripsy to break urinary stones, urologists frequently see flashes of light. As infrared laser pulses are invisible, what is the source of light? Here we studied the origin, characteristics, and some effects of flashes of light in laser lithotripsy.MethodsUltrahigh‐speed video‐microscopy was used to record single laser pulses at 0.2–1.0 J energy lasered with 242 µm glass‐core‐diameter fibers in contact with whole surgically retrieved urinary stones and hydroxyapatite (HA)‐coated glass slides in air and water. Acoustic transients were measured with a hydrophone. Visible‐light and infrared photodetectors resolved temporal profiles of visible‐light emission and infrared‐laser pulses.ResultsTemporal profiles of laser pulses showed intensity spikes of various duration and amplitude. The pulses were seen to produce dim light and bright sparks with submicrosecond risetime. The spark produced by the intensity spike at the beginning of laser pulse generated a shock wave in the surrounding liquid. The subsequent sparks were in a vapor bubble and generated no shock waves. Sparks enhanced absorption of laser radiation, indicative of plasma formation and optical breakdown. The occurrence and number of sparks varied even with the same urinary stone. Sparks were consistently observed at laser energy >0.5 J with HA‐coated glass slides. The slides broke or cracked by cavitation with sparks in 63 ± 15% of pulses (1.0 J,N= 60). No glass‐slide breakage occurred without sparks (1.0 J,N= 500).ConclusionUnappreciated in previous studies, plasma formation with free‐running long‐pulse holmium:YAG lasers can be an additional physical mechanism of action in laser procedures.