The interaction between excimer laser energy and vascular tissue.

Area of Science:

• Biomedical Engineering
• Laser Physics
• Cardiovascular Research

Background:

• Atherosclerosis poses significant challenges in vascular interventions.
• Precise removal of vascular tissue is crucial for surgical procedures.
• Excimer lasers offer potential for minimally invasive treatments.

Purpose of the Study:

• To investigate the effects of XeF excimer laser on normal and atherosclerotic aorta.
• To determine the parameters influencing precise vascular tissue ablation.
• To evaluate the photothermal mechanisms involved in laser ablation.

Main Methods:

• Experiments conducted in flowing water with controlled parameters (temperature, flow rate, pulse width, wavelength, beam size, focal length).
• Varied pulse number, energy, and frequency to study tissue response.
• Histological analysis of vascular tissue post-laser exposure.
• Investigated plaque photoresistance and laser energy attenuation by blood.

Main Results:

• Vascular tissue ablation requires a minimum pulse energy threshold and is proportional to pulse energy and number of pulses.
• Precise ablation observed at low pulse frequencies; thermal effects increased with higher frequencies.
• Calcified plaque demonstrated higher photoresistance compared to atheroma and normal tissue.
• Blood significantly attenuated excimer laser energy.

Conclusions:

• Excimer laser enables rapid and precise ablation of vascular tissue.
• Ablation precision is linked to pulse interval and high peak power.
• The process involves photothermal mechanisms for vascular tissue removal.