Ex vivo study of Ho:YAG and thulium fiber lasers for soft tissue surgery: which laser for which case?

The goal of this study was to assess the ablation, coagulation, and carbonization characteristics of the holmium:YAG (Ho:YAG) laser and thulium fiber lasers (TFL). The Ho:YAG laser (100 W av.power), the quasi-continuous (QCW) TFL (120 W av.power), and the SuperPulsed (SP) TFL (50 W av.power) were compared on a non-frozen porcine kidney. To control the cutting speed (2 or 5 mm/s), an XY translation stage was used. The Ho:YAG was tested using E = 1.5 J and P-av = 40 W or P-av = 70 W settings. The TFL was tested using E = 1.5 J and P-av = 30 W or P-av = 60 W settings. After ex vivo incision, histological analysis was performed in order to estimate thermal damage. At 40 W, the Ho:YAG displayed a shallower cutting at 2 and 5 mm/s (1.1 +/- 0.2 mm and 0.5 +/- 0.2 mm, respectively) with virtually zero coagulation. While at 70 W, the minimal coagulation depth measured 0.1 +/- 0.1 mm. The incisions demonstrated zero carbonization. Both the QCW and SP TFL did show effective cutting at all speeds (2.1 +/- 0.2 mm and 1.3 +/- 0.2 mm, respectively, at 30 W) with prominent coagulation (0.6 +/- 0.1 mm and 0.4 +/- 0.1 mm, respectively, at 70 W) and carbonization. Our study introduced the TFL as a novel efficient alternative for soft tissue surgery to the Ho:YAG laser. The SP TFL offers a Ho:YAG-like incision, while QCW TFL allows for fast, deep, and precise cutting with increased carbonization.

Automated summary

This study assessed the ablation, coagulation, and carbonization characteristics of the Ho:YAG laser and TFL. The results showed that the Ho:YAG laser had shallower cutting and minimal coagulation at lower power settings, while the TFL demonstrated effective cutting, prominent coagulation, and carbonization at all speeds. The study introduced TFL as an efficient alternative for soft tissue surgery to the Ho:YAG laser.