Experimental ex-vivo performance study comparing a novel, pulsed thulium solid-state laser, chopped thulium fibre laser, low and high-power holmium:YAG laser for endoscopic enucleation of the prostate

Abstract

Purpose The aim of this study was to compare the enucleation performances of four different types of laser devices in an ex-vivo experiment: a novel, pulsed Tm:YAG solid-state laser evaluation model (p-Tm:YAG), chopped thulium fibre laser (TFL), low-power Ho:YAG laser (LP-Ho:YAG), and a high-power Ho:YAG laser (HP-Ho:YAG). Methods Our primary aim was to endoscopically separate the fascial layers of a porcine belly using laser fibres within a time period of 60 s. The size of a “tissue pocket” was assessed numerically. The enucleation characteristics reflecting the surgeon’s experience were evaluated via the NASA Task Load Index (TLX) questionnaire and a questionnaire based on Likert scale. Results HP-Ho:YAG achieved with the available laser settings the largest overall “tissue pocket” (31.5 cm2) followed by p-Tm:YAG (15 cm2), TFL (12 cm2), and LP-Ho:YAG (6 cm2). The coagulation performances of p-Tm:YAG and TFL were rated the best. In the performance evaluation by the Likert questionnaire, HP-Ho:YAG (average score of 4.06) was rated highest, followed by p-Tm:YAG (3.94), TFL (3.38), and LP-Ho:YAG (3.25). The evaluation of the NASA-TLX performance questionnaire revealed average scores for HP-Ho:YAG, LP-Ho:YAG, TFL and p-Tm:YAG of 4.38, 4.09, 3.92 and 3.90, respectively. Conclusion We are the first to compare different laser devices and settings in an ex-vivo study. We found that the surgeons were most satisfied with the HP-Ho:YAG laser device, followed by the p-Tm:YAG. These findings could be highly relevant for future research and for the practical utilisation of laser systems in endourology.

Thulium fiber laser in BPH surgery: Bench to bedside - a systematic review on behalf of YAU Urotechnology Working Group

“…If our assumption is correct, carbonization may also be lower when using TFL. In comparing TFL and pulsed Tm : YAG (27), no significant differences were found. That can be explained by the change of laser pulse generation.…”

“…Yilmaz et al (27) in their study tried to simulate the prostate enucleation process using a model of porcine belly. The researchers compared the speed of anterior abdominal wall fascial layers with separation, coagulation performance of lasers and the ease with which the surgeon could operate.…”

Thulium fiber laser vs. holmium laser enucleation of the prostate: results of a prospective randomized non-inferiority trial

“…Discussions about possible safety differences between TFL and holmium laser arose from the same reasons as mentioned above regarding functional outcomes [ 11 ]. The first ex vivo trials showed significant differences between the laser sources with improved hemostatic effect [ 11 , 14 , 16 ]. On the contrary, one ex vivo trial showed comparable coagulation between the two laser sources and another ex vivo trial even postulated a significant better coagulation with the holmium laser than with TFL [ 25 , 26 ].…”

“…Tissue rupturing due to fast vaporization of the water between laser fiber and tissue as it is typical for the holmium laser may achieve better tissue separation than a sharp incision which is typical for the TFL [ 11 ]. In two ex vivo trials the tissue separation depth was greater with the holmium laser than TFL and objectively preferred by the surgeons [ 16 , 25 ]. In three in vivo studies available to date, ThuFLEP was equivalent to HoLEP in terms of enucleation time and efficiency [ 10 , 12 , 18 ].…”

“…The TFL allows a wide variety of laser settings [ 11 ]. The potentially harmful effects are described as reduced while the hemostatic effect appears to be improved [ 11 , 14 , 16 ]. Due to less vaporization of the water between laser fiber and tissue TFL creates less bursting energy for tissue dissection and therefore has an improved cutting efficiency [ 11 , 15 ].…”