Barton J K, Hammer D X, Pfefer T J, Lund D J, Stuck B E, Welch A J
Biomedical Engineering Program, University of Arizona, Tucson 85721-0104, USA.
Lasers Surg Med. 1999;24(3):236-43. doi: 10.1002/(sici)1096-9101(1999)24:3<236::aid-lsm9>3.0.co;2-i.
Simultaneous irradiation and viewing of 10-120 microm cutaneous blood vessels were performed to investigate the effects of 2-micros 577-nm dye laser pulses.
STUDY DESIGN/MATERIALS AND METHODS: A modified scanning laser confocal microscope recorded vessel response to different radiant exposures (J/cm2). Probit analysis determined the 50% probability ("threshold") radiant exposure necessary to cause embolized or partly occluding coagula, coagula causing complete blood flow stoppage, and hemorrhage.
A statistically significant difference in the threshold radiant exposure existed for each damage category for blood vessels 10-30 microm in diameter, but not for larger vessels. For vessels over 60 microm, complete flow stoppage was unattainable; increasing laser pulse energy produced hemorrhage. In larger vessels, coagula often were attached to the superficial vessel wall while blood flowed underneath. Monte Carlo optical and finite difference thermal modeling confirmed experimental results.
These results provide insight into the role of pulse duration and vessel diameter in the outcome of pulsed dye laser irradiation.
对10 - 120微米的皮肤血管进行同步照射和观察，以研究2微秒577纳米染料激光脉冲的效果。
研究设计/材料与方法：一台改良的扫描激光共聚焦显微镜记录血管对不同辐射暴露量（焦耳/平方厘米）的反应。概率分析确定引起栓塞或部分阻塞性凝块、导致血流完全停止的凝块以及出血所需的50%概率（“阈值”）辐射暴露量。
对于直径10 - 30微米的血管，每种损伤类型的阈值辐射暴露量存在统计学显著差异，但较大血管则不存在。对于直径超过60微米的血管，无法实现血流完全停止；增加激光脉冲能量会导致出血。在较大血管中，凝块常附着于血管浅表壁，而血液在其下方流动。蒙特卡罗光学和有限差分热模型证实了实验结果。
这些结果为脉冲持续时间和血管直径在脉冲染料激光照射结果中的作用提供了见解。
