Due to wavelength-specific water absorption, infrared lasers like the thulium laser emitting at 1940 nm wavelength proved to be suitable for coagulation in neurosurgery. Commonly bipolar forceps used for intraoperative haemostasis can cause mechanical and thermal tissue damage, whilst thulium laser can provide a tissue-gentle haemostasis through non-contact coagulation. The aim of this work is a less-damaging blood vessel coagulation by pulsed thulium laser radiation in comparison to standard bipolar forceps haemostasis. Ex vivo porcine blood vessels in brain tissue (0.34 ± 0.20 mm diameter) were irradiated in non-contact with a thulium laser in pulsed mode (1940 nm wavelength, 15 W power, 100–500 ms pulse duration), with a CO₂ gas flow provided simultaneously at the distal fibre tip (5 L/min). In comparison, a bipolar forceps was used at various power levels (20–60 W). Tissue coagulation and ablation were evaluated by white light images and vessel occlusion was visualised by optical coherence tomography (OCT) B-scans at a wavelength of 1060 nm. Coagulation efficiency was calculated by means of the quotient of the difference between the coagulation and ablation radius to the coagulation radius. Pulsed laser application achieved blood vessel occlusion rate of 92% at low pulse duration of 200 ms with no occurrence of ablation (coagulation efficiency 100%). Bipolar forceps showed an occlusion rate of 100%, however resulted in tissue ablation. Tissue ablation depth with laser application is limited to 40 μm and by a factor of 10 less traumatising than with bipolar forceps. Pulsed thulium laser radiation achieved blood vessel haemostasis up to 0.3 mm in diameter without tissue ablation and has proven to be a tissue-gentle method compared to bipolar forceps.

由于特定波长的吸水性，红外激光器（如以 1940 nm 波长发射的铥激光器）被证明适用于神经外科手术中的凝固。通常用于术中止血的双极钳会造成机械和热组织损伤，而铥激光可通过非接触式凝固提供组织温和的止血。这项工作的目的是与标准双极钳止血相比，脉冲铥激光辐射对血管的损伤更小。离体猪脑组织血管（直径 0.34 ± 0.20 mm）在脉冲模式（1940 nm 波长，15 W 功率，100-500 ms 脉冲持续时间）下以非接触方式用 CO ₂在远端纤维尖端 (5 L/min) 同时提供的气流。相比之下，双极钳在不同功率水平（20-60 W）下使用。通过白光图像评估组织凝固和消融，并通过 1060 nm 波长的光学相干断层扫描 (OCT) B 扫描可视化血管闭塞。凝血效率通过凝血和消融半径之差与凝血半径的商计算。脉冲激光应用在 200 毫秒的低脉冲持续时间下实现了 92% 的血管闭塞率，并且没有发生消融（凝血效率 100%）。双极钳显示 100% 的闭塞率，但导致组织消融。激光应用的组织消融深度限制在 40 μm，并且创伤比双极钳小 10 倍。