Fractional laser photothermolysis using Bessel beams

Area of Science:

• Biomedical Optics
• Dermatology
• Laser Physics

Background:

• Fractional photothermolysis (FP) utilizes laser-induced microscopic thermal lesions to stimulate skin collagen remodeling.
• Conventional Gaussian beams are typically used for creating these lesions in FP treatments.

Purpose of the Study:

• To investigate Bessel beams as an alternative to Gaussian beams for creating laser photothermal lesions in skin.
• To evaluate the impact of Bessel beams on the aspect ratio (depth-to-diameter) of thermal lesions.

Main Methods:

• Numerical simulations using electric field Monte Carlo photon transport and finite difference methods.
• Application of the Arrhenius model to predict thermal damage.
• Experimental validation using ex vivo human skin samples.

Main Results:

• Bessel beams demonstrated a superior depth-to-diameter aspect ratio for photothermal lesions compared to Gaussian beams.
• Optimized lesion geometry for enhanced therapeutic outcomes was achieved using Bessel beams.
• Simulations and experimental results showed consistent improvements in lesion characteristics.

Conclusions:

• Bessel beams offer a significant advantage over Gaussian beams in fractional photothermolysis.
• The ability to create deep, narrow thermal lesions with Bessel beams can lead to improved treatment efficacy.
• This research paves the way for more effective laser-based skin rejuvenation therapies.