Laser light has been widely used as a surgical tool to treat benign prostate hyperplasia with high laser power.
The purpose of this study was to validate the feasibility of photoactive dye injection to enhance light absorption
and eventually to facilitate tissue ablation with low laser power. The experiment was implemented on chicken
breast due to minimal optical absorption Amaranth (AR), black dye (BD), hemoglobin powder (HP), and
endoscopic marker (EM), were selected and tested in vitro with a customized 532-nm laser system with radiant
exposure ranging from 0.9 to 3.9 J/cm<sup>2</sup>. Light absorbance and ablation threshold were measured with UV-VIS
spectrometer and Probit analysis, respectively, and compared to feature the function of the injected dyes.
Ablation performance with dye-injection was evaluated in light of radiant exposure, dye concentration, and
number of injection. Higher light absorption by injected dyes led to lower ablation threshold as well as more
efficient tissue removal in the order of AR, BD, HP, and EM. Regardless of the injected dyes, ablation
efficiency principally increased with input parameter. Among the dyes, AR created the highest ablation rate of
44.2±0.2 μm/pulse due to higher absorbance and lower ablation threshold. Preliminary tests on canine prostate
with a hydraulic injection system demonstrated that 80 W with dye injection yielded comparable ablation
efficiency to 120 W with no injection, indicating 33 % reduced laser power with almost equivalent performance.
In-depth comprehension on photoactive dye-enhanced tissue ablation can help accomplish efficient and safe
laser treatment for BPH with low power application.