Sapphire probe laser ablation of human arteries with CO2 gas and saline perfusion: The effect of flow rate, lasing power and lasing time

Abstract

To evaluate flow rate dependence of CO2 gas and saline perfusion for sapphire probe ablation, all together 204 human arterial specimens of atheroma and normal vessel were irradiated with Nd-YAG laser, in an experimental circulation-occlusion model within 37°C flowing whole blood. During lasing procedures, various flow rates of CO2 gas (0.2–2.01 min−1) and saline (2.0–20.0 ml min−1), and various lasing powers (7, 12 and 17 W) and lasing time (1–20 s) were used. Histological changes of all specimens irradiated were microscopically examined. The results showed that the laser ablation area enlarged with increasing CO2 flow rates and decreasing saline flow rates. Relative ablation efficiency on atheromatous plaque, in comparison to those on normal vessel wall and surrounding tissue site, increased slightly with increasing lasing power and lasing time. In this experimental setting, the mode of action of the sapphire probe ablation on human arterial atheroma seems to be more satisfactory with CO2 gas perfusion than with saline perfusion.