Department of Physics and Optical Science, University of North Carolina at Charlotte, Charlotte, North Carolina, USA.
Department of Mechanical Engineering, University of North Carolina at Charlotte, Charlotte, North Carolina, USA.
Lasers Surg Med. 2023 Dec;55(10):886-899. doi: 10.1002/lsm.23740. Epub 2023 Nov 27.
Infrared (IR) lasers are being tested as an alternative to radiofrequency (RF) and ultrasonic (US) surgical devices for hemostatic sealing of vascular tissues. In previous studies, a side-firing optical fiber with elliptical IR beam output was reciprocated, producing a linear IR laser beam pattern for uniform sealing of blood vessels. Technical challenges include limited field-of-view of vessel position within the metallic device jaws, and matching fiber scan length to variable vessel sizes. A transparent jaw may improve visibility and enable custom treatment.
Quartz and sapphire square optical chambers (2.7 × 2.7 × 25 [mm ] outer dimensions) were tested, capable of fitting into a 5-mm-OD laparoscopic device. A 1470 nm laser was used for optical transmission studies. Razor blade scans and an IR beam profiler acquired fiber (550-µm-core/0.22NA) output beam profiles. Thermocouples recorded peak temperatures and cooling times on internal and external chamber surfaces. Optical fibers with angle polished distal tips delivered 94% of light at a 90° angle. Porcine renal arteries with diameters of 3.4 ± 0.7 mm (n = 13) for quartz and 3.2 ± 0.7 mm (n = 14) for sapphire chambers (p > 0.05), were sealed using 30 W for 5 s.
Reflection losses at material/air interfaces were 3.3% and 7.4% for quartz and sapphire. Peak temperatures on the external chamber surface averaged 74 ± 8°C and 73 ± 10°C (p > 0.05). Times to cool down to 37°C measured 13 ± 4 s and 27 ± 7 s (p < 0.05). Vessel burst pressures (BP) averaged 883 ± 393 mmHg and 412 ± 330 mmHg (p < 0.05). For quartz, 13/13 (100%) vessels were sealed (BP > 360 mmHg), versus 9/14 (64%) for sapphire. Computer simulations for the quartz chamber yielded peak temperatures (78°C) and cooling times (16 s) similar to experiments.
Quartz is an inexpensive material for use in a laparoscopic device jaw, providing more consistent vessel seals and faster cooling times than sapphire and current RF and US devices.
红外（IR）激光正被测试作为替代射频（RF）和超声（US）手术设备，用于血管组织的止血密封。在以前的研究中，使用侧向发射的光纤，具有椭圆形的 IR 光束输出，进行往复运动，产生用于均匀密封血管的线性 IR 激光束图案。技术挑战包括在金属器械钳口中血管位置的有限视野，以及将光纤扫描长度与可变的血管尺寸相匹配。透明的钳口可以提高可视性并实现定制的治疗。
测试了石英和蓝宝石方形光学腔（2.7×2.7×25[mm]外部尺寸），能够装入 5-mm-OD 腹腔镜器械。使用 1470nm 激光进行光学传输研究。使用剃刀刀片扫描和 IR 光束轮廓仪获取光纤（550-μm 芯/0.22NA）输出光束轮廓。热电偶记录内部和外部腔表面的峰值温度和冷却时间。具有角度抛光远端尖端的光纤以 90°角传输 94%的光。直径为 3.4±0.7mm（n=13）的石英和 3.2±0.7mm（n=14）的蓝宝石腔的猪肾动脉（p>0.05），使用 30W 功率密封 5s。
石英和蓝宝石的材料/空气界面反射损耗分别为 3.3%和 7.4%。外部腔表面的峰值温度平均为 74±8°C 和 73±10°C（p>0.05）。降至 37°C 的冷却时间分别为 13±4s 和 27±7s（p<0.05）。血管爆裂压力（BP）平均为 883±393mmHg 和 412±330mmHg（p<0.05）。对于石英，13/13（100%）的血管被密封（BP>360mmHg），而蓝宝石为 9/14（64%）。石英腔的计算机模拟得到的峰值温度（78°C）和冷却时间（16s）与实验相似。
石英是一种用于腹腔镜器械钳口的廉价材料，与蓝宝石和当前的 RF 和 US 设备相比，它能提供更一致的血管密封和更快的冷却时间。
