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.

由于具有特定波长的水吸收，红外激光（例如发射 1940 nm 波长的铥激光）被证明适用于神经外科手术中的凝血。通常用于术中止血的双极钳会导致机械和热组织损伤，而铥激光可以通过非接触性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，通过脉冲铥激光辐射实现损伤更小的血管凝固。使用 CO ₂气体，以脉冲模式（1940 nm 波长，15 W 功率，100–500 ms 脉冲持续时间）铥激光对脑组织中的离体猪血管（直径 0.34 ± 0.20 mm）进行非接触式照射在远端纤维尖端同时提供流量 (5 L/min)。相比之下，双极镊子在不同功率水平（20-60 W）下使用。通过白光图像评估组织凝固和消融，并通过波长为 1060 nm 的光学相干断层扫描 (OCT) B 扫描来可视化血管闭塞。凝血效率通过凝血半径和消融半径之差除以凝血半径的商来计算。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（凝固效率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仅限于 40 μm，并且比双极钳的创伤小 10 倍。脉冲铥激光辐射可实现直径达 0.3 毫米的血管止血，且无需消融组织，与双极镊子相比，已被证明是一种对组织温和的方法。