Effects of Different 980‐nm Diode Laser Parameters in Hepatectomy

Abstract

Background and Objective: Despite the successful application of laser in animal experiments and clinics, the adjustment of laser parameters during surgery is still unclear. This study aimed to investigate the effect of different 980-nm diode laser parameters in hepatectomy. This could provide a clear protocol for using 980-nm diode laser in hepatectomy. Study Design/Materials and Methods: In total, 48 Sprague-Dawley rats were used to explore the effects of different 980-nm diode laser parameters in hepatectomy, by setting different parameter combinations. The rats were randomly divided into eight groups, including the continuous wave group and quasi-continuous wave group. The effects were assessed in terms of liver resection speed, extent of intraoperative bleeding, and thermal damage. Results: In the quasi-continuous wave group, there was a significant difference in resection speed at the different laser parameters (P < 0.001); however, there was no significant difference in intraoperative bleeding and thermal damage. In the continuous wave group, there was a significant difference in resection speed, intraoperative bleeding, and thermal damage at different parameters. Conclusion: The study showed that the average power determined hemostasis efficiency and thermal damage, and peak power determined the liver resection speed, whereas the pulse width and repetition frequency are not independent factors. When using 980-nm diode laser in hepatectomy, the average power should be decreased to prove hemostasis efficiency in delicate operations, and the peak power should be decreased to accelerate the procedure without worsening thermal damage. Lasers Surg. Med. 1--8, 2018.

Effects of water cooling on laser‐induced thermal damage in rat hepatectomy

“…In our previous study, we explored the effects of different 980-nm diode laser parameters in hepatectomy. 25 Based on this, the main observation indicators of the study were resection efficiency and thermal damage in different methods, including each area of the thermal damage zone, seeking a more reasonable and safe thermal damage control strategy. Thermal damage was evaluated using a histological specimen, hematoxylin-eosin (HE) stain, to obtain the thermal damage area of each zone.…”

“…Water cooling is the continuous instillation of normal saline solution during a laser hepatectomy. Our previous studies demonstrated that thermal damage also increases with increasing laser output power 25 . Therefore, the output power should be adjusted to as low as possible to achieve similar cutting effects.…”

“…Our previous studies demonstrated that thermal damage also increases with increasing laser output power. 25 Therefore, the output power should be adjusted to as low as possible to achieve similar cutting effects. At the same output power, the thermal damage caused by changes in the quasi-continuous wave (QCW) mode is not statistically significant, which may be due to the superimposed effect of the pulsed laser during the entire operation.…”

Optical Coherence Tomography/Angiography-Guided Tumor Ablation With a Continuous-Wave Laser Diode

“…In the past, various lasers such as CO 2 and Nd:YAG ones were utilized for medical treatment [7], [8]. It was also demonstrated that either continuous-wave (CW) or pulsed-mode lasers could be used for laser therapy [9], [10]. In clinical applications, short-pulse lasers represent the most commonly used therapeutic tool because they are able to damage the irradiated tissues without melting the surrounding before heat accumulation occurs [11].…”