What factors determine the depth of penetration in laser treatments?

The factors that determine the depth of penetration in laser treatments primarily include the wavelength and spot size. The wavelength of the laser light plays a crucial role because different wavelengths are absorbed by different types of tissues. For instance, longer wavelengths penetrate deeper into the skin, while shorter wavelengths may be absorbed more superficially. This allows the practitioner to select a wavelength that targets specific tissues effectively, depending on the desired outcome of the treatment.

Spot size, on the other hand, affects the distribution of energy across the area being treated. A larger spot size can cover a larger area and may allow for deeper penetration, while a smaller spot size focuses energy on a smaller target area, enhancing the intensity of treatment at that specific site. Thus, both wavelength and spot size collaboratively influence how deeply the laser energy can penetrate the skin, ultimately affecting the effectiveness and safety of the treatment.

While other factors such as fluence, pulse width, energy output, duration, beam diameter, and tissue type also play roles in laser treatments, it is the combination of wavelength and spot size that predominantly influences penetration depth.