In vitro evaluation of the safety and efficacy of a high-power 450-nm semiconductor blue laser in the treatment of benign prostate hyperplasia

Abstract

A 450-nm blue laser may be suitable to treat benign prostate hyperplasia (BPH) due to its haemoglobin absorption characteristic. The present study compared a novel high-power 450-nm semiconductor blue laser with other lasers marketed for in vitro soft tissue ablation, to evaluate the safety and efficacy of the 450-nm laser in BPH surgery. With the in vitro tissues on an experimental platform in water, the vaporization efficiency and coagulation layer thickness of the novel 450-nm laser and commercially available 532-nm, 980-nm, and 1470-nm lasers were measured at the same power (120 W). The damage to the adjacent tissue and the working noise were also measured. The vaporization efficiency was proved to be 450-nm laser > 532-nm laser > 1470-nm laser > 980-nm laser. Comparison of coagulation layer thickness was as follow: 980-nm laser > 1470-nm laser > 532-nm laser > 450-nm laser. The degree of tissue damage caused by the 450-nm and 532-nm lasers increased with the decrease in distance and increase in time (these are safe when a sufficient distance and short irradiation time are maintained). The heating ability of 980-nm and 1470-nm lasers was much greater than that of 450-nm and 532-nm lasers. The working noise was lower in 450-nm and 1470-nm lasers. The novel 450-nm laser has the advantages of highly efficient tissue vaporization, creating a thin coagulation layer, and low working noise. These characteristics suggest that the novel 450-nm laser may be a promising choice for the surgical treatment of BPH.

Keywords: 1470-nm laser; 450-nm semiconductor blue laser; 532-nm laser; 980-nm laser; Benign prostatic hyperplasia.