Modeling of (coronary) laser-angioplasty

A first attempt to describe (coronary) laser angioplasty is presented using simplified but standard optical and thermal modeling of tissue in interaction with a laser. Ablation behavior of blood thrombi and plaque has been approximated from numerical computations for various wavelengths representing the Ar, Nd-YAG, and CO2 lasers. The overall results, in terms of calculated depth of ablation versus laser irradiation time, show a relatively fast initial process followed by a very slow one. The analysis suggests that a sequence of laser pulse-catheter tip flushing should substantially increase the overall ablation velocity. The physics of threshold laser power and influence of laser beam diameter is discussed. A comparison between experimental results is made when possible. Suggestions for further test experiments are made.