Comparative Morphometric and Histometric Evaluation of Power-Dependent Tissue Ablation Using Fractional Carbon...

Area of Science:

• Dermatology
• Laser Physics
• Biomedical Engineering

Background:

• Fractional carbon dioxide (CO2) lasers are standard for skin resurfacing, enabling precise ablation and dermal remodeling.
• Clinical results vary with laser settings, but data comparing power-dependent tissue effects are scarce.

Purpose of the Study:

• To compare the ablation characteristics of microscopic thermal zones (MTZs) created by fractional CO2 lasers at 30W and 40W peak powers.
• To evaluate power-dependent tissue interactions using an ex vivo porcine skin model.

Main Methods:

• Ex vivo porcine skin samples were treated with a fractional CO2 laser (40-240 mJ) at 30W and 40W settings.
• Ablation depth was assessed histologically at physiological temperatures, while diameters were measured dermoscopically on frozen samples.
• Morphometric and histometric analyses were statistically evaluated.

Main Results:

• Both 30W and 40W settings showed energy-dependent increases in ablation depth and diameter.
• The 40W laser produced significantly deeper ablation columns (11.8% deeper on average) and narrower surface diameters (7.3% narrower) with less carbonization.
• Higher slope coefficients in the 40W group indicated greater ablation efficiency.

Conclusions:

• The 40W fractional CO2 laser provides enhanced precision, deeper penetration, and reduced thermal diffusion compared to 30W.
• Higher peak power settings may improve the safety and efficacy of fractional skin resurfacing, especially for darker skin types.