University of North Carolina at Charlotte, Department of Physics and Optical Science, 9201 University City Boulevard, Charlotte, North Carolina 28223.
Covidien, 5920 Longbow Drive, Boulder, Colorado 80301.
J Biomed Opt. 2014 Mar;19(3):38002. doi: 10.1117/1.JBO.19.3.038002.
Suture ligation with subsequent cutting of blood vessels to maintain hemostasis during surgery is time consuming and skill intensive. Energy-based electrosurgical and ultrasonic devices are often used to replace sutures and mechanical clips to provide rapid hemostasis and decrease surgery time. Some of these devices may create undesirably large collateral zones of thermal damage and tissue necrosis, or require separate mechanical blades for cutting. Infrared lasers are currently being explored as alternative energy sources for vessel sealing applications. In a previous study, a 1470-nm laser was used to seal vessels 1 to 6 mm in diameter in 5 s, yielding burst pressures of ∼500 mmHg. The purpose of this study was to provide vessel sealing times comparable with current energy-based devices, incorporate transection of sealed vessels, and demonstrate high vessel burst pressures to provide a safety margin for future clinical use. A 110-W, 1470-nm laser beam was transmitted through a fiber and beam shaping optics, producing a 90-W linear beam 3.0 by 9.5 mm for sealing (400 W/cm2), and 1.1 by 9.6 mm for cutting (1080 W/cm2). A two-step process sealed and then transected ex vivo porcine renal vessels (1.5 to 8.5 mm diameter) in a bench top setup. Seal and cut times were 1.0 s each. A burst pressure system measured seal strength, and histologic measurements of lateral thermal spread were also recorded. All blood vessels tested (n=55 seal samples) were sealed and cut, with total irradiation times of 2.0 s and mean burst pressures of 1305±783 mmHg. Additional unburst vessels were processed for histological analysis, showing a lateral thermal spread of 0.94±0.48 mm (n=14 seal samples). This study demonstrated that an optical-based system is capable of precisely sealing and cutting a wide range of porcine renal vessel sizes and, with further development, may provide an alternative to radiofrequency- and ultrasonic-based vessel sealing devices.
手术中，为了止血，结扎血管后再进行切割，既耗时又需要技巧。能量型电外科和超声设备常用于替代缝线和机械夹，以实现快速止血并缩短手术时间。这些设备中的一些可能会造成不理想的大面积热损伤和组织坏死的附带区域，或者需要单独的机械刀片进行切割。目前，红外激光器正被探索作为血管密封应用的替代能源。在之前的一项研究中，使用 1470nm 激光在 5s 内密封 1 至 6mm 直径的血管，产生的爆裂压力约为 500mmHg。本研究的目的是提供与当前能量型设备相当的血管密封时间，结合密封血管的横切，并展示高血管爆裂压力，为未来的临床应用提供安全裕度。110W 的 1470nm 激光束通过光纤和光束整形光学元件传输，产生用于密封（400W/cm2）的 90W 线性光束 3.0×9.5mm，用于切割（1080W/cm2）的 1.1×9.6mm。两步法在台面上密封并横切离体猪肾血管（1.5 至 8.5mm 直径）。密封和切割时间均为 1.0s。爆裂压力系统测量密封强度，还记录了横向热扩散的组织学测量结果。所有测试的血管（n=55 个密封样本）均被密封和切割，总辐照时间为 2.0s，平均爆裂压力为 1305±783mmHg。对额外未爆裂的血管进行组织学分析，显示横向热扩散为 0.94±0.48mm（n=14 个密封样本）。本研究表明，基于光学的系统能够精确地密封和切割广泛的猪肾血管尺寸，如果进一步开发，可能会替代射频和超声血管密封设备。
