Department of Urology, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich, Germany.
J Endourol. 2011 Apr;25(4):667-72. doi: 10.1089/end.2010.0169. Epub 2011 Mar 7.
During laser lithotripsy, working instruments are often in close proximity to the distal fiber tip and may be damaged accidentally or even intentionally. The aim of this study was to compare the amount of damage to a standard guidewire and the nitinol wires of endourologic retrieval baskets that were affected by three different clinically available laser systems.
The impact of pulsed laser irradiation on a standard hydrophilic guidewire and a retrieval basket were investigated. One infrared (IR) laser system (holmium:yttrium-aluminum-garnet [Ho:YAG]: λ = 2100 nm) and two laser systems emitting light in the visible (VIS) spectral range (frequency-doubled double-pulse neodymium:YAG [FREDDY]: λ = 532 nm/1064 nm and flashlamp pulsed dye [FLPD]: λ = 598 nm) were used. Experimental parameters were fiber core diameter, laser pulse energy, and distance between the fiber tip and the investigated tool. Damage was evaluated by microscopic investigation and by quantifying the damage size and magnitude by creating laser impact related damage factors.
After application of one single laser pulse, IR-laser related maximum damage to guidewires occurred, depending on the pulse energy and the fiber core diameter, either in contact mode or in a distance of maximum 2 mm. Maximum VIS-laser related damage occurred in a distance range of 2 to 3 mm. The nitinol wires of the extraction tools could be destroyed completely by IR laser irradiation at pulse energies E(P) > 1200 mJ, depending on the fiber core diameter used. VIS lasers were solely able to set visible damage to guidewires without any disruption of nitinol wires.
Ho:YAG laser induced damage to endourologic tools is significantly higher compared with the impact of the FREDDY or the FLPD-laser. Because complete disruption of guidewires and stone extraction tools occurred, a safety clearance must be kept between the fiber tip and the endourologic tool during Ho:YAG stone disintegration. If disruption is intended, such as in the case of basket-retrieval problems, it can easily be performed with Ho:YAG irradiation.
在激光碎石术中，工作器械通常靠近远端光纤尖端，可能会意外甚至故意损坏。本研究的目的是比较三种不同的临床可用激光系统对标准导丝和腔内取石篮的镍钛诺丝造成的损伤程度。
研究了脉冲激光照射对标准亲水导丝和取石篮的影响。使用了一种红外（IR）激光系统（钬：钇-铝-石榴石[Ho:YAG]：λ=2100nm）和两种发射可见光（VIS）光谱范围激光的系统（倍频双脉冲钕：YAG[FREDDY]：λ=532nm/1064nm 和闪光灯脉冲染料[FLPD]：λ=598nm）。实验参数为光纤芯径、激光脉冲能量以及光纤尖端与被研究工具之间的距离。通过显微镜检查和创建与激光撞击相关的损伤因子来量化损伤大小和程度来评估损伤。
在应用单个激光脉冲后，IR 激光相关的导丝最大损伤取决于脉冲能量和光纤芯径，要么在接触模式下，要么在距离最大 2mm 内。VIS 激光相关的最大损伤发生在 2 到 3mm 的距离范围内。取决于所用光纤芯径，IR 激光辐照可完全破坏提取工具的镍钛诺丝，当脉冲能量 E(P)>1200mJ 时。VIS 激光仅能在不破坏镍钛诺丝的情况下对导丝造成可见损伤。
与 FREDDY 或 FLPD 激光的影响相比，钬：YAG 激光对腔内工具的损伤要高得多。由于导丝和结石提取工具完全断裂，在 Ho:YAG 结石分解过程中，光纤尖端和腔内工具之间必须保持安全间隙。如果意图中断，例如在取石篮取石问题的情况下，很容易用 Ho:YAG 照射来完成。
