Impact of different color fiber sleeves on beam hazards of 532-nm laser and vaporization efficiency

Abstract

The 532-nm laser has become increasingly popular for the treatment of urologic diseases. However, laser beam will pose significant hazards for the health of surgeons. In order to reduce beam hazards during surgery, we compared the beam hazards of laser fiber with black sleeves to the traditional fiber with transparent sleeves, and the vaporization efficiency. A total of 18 porcine kidney specimens were vaporized in normal saline at a room temperature under 532-nm laser delivered through a 760-μm core diameter side firing fiber. Two groups were divided according to the color of fiber sleeves: the transparent and the black. Each group was then divided into another three subgroups by laser power: the 80 W group, the 120 W group, and the 160 W group. The beam hazard was evaluated by light intensity measured in a sector area at a distance of 0 m, 0.5 m, and 1 m from the irradiation center. The vaporization efficiency was measured by the vaporization groove depth under the working power of 80 W, 120 W, and 160 W with a working distance of 5 mm and irradiation time of 10 s. The light intensity measured in the black fiber sleeve group is significantly lower than that in the transparent one (P < 0.01), regardless of the measuring distance (0 m, 0.5 m, and 1.0 m) and laser power (80 W, 120 W, and 160 W). No statistical difference was found on the vaporization efficiency between the groups protected by fiber sleeves of different colors (transparent/black, p > 0.05). Compared to the traditional transparent fiber sleeves, more beam hazards will be reduced in the operative region with the protection of black fiber sleeves, especially those from the irradiation center. The vaporization efficiency is not affected by the color of fiber sleeves. Such findings may offer a completely new idea for the protection of surgeons in surgeries with 532-nm lasers.

Keywords: Efficiency; Laser therapy; Lasers; Photoselective vaporization of prostate (PVP); Safety.