You have full access to this open access article. Penetration depth of ultraviolet, visible light and infrared radiation in biological tissue has not previously been adequately measured. Risk assessment of typical intense pulsed light and laser intensities, spectral characteristics and the subsequent chemical, physiological and psychological effects of such outputs on vital organs as consequence of inappropriate output use are examined.
This technical note focuses on wavelength, illumination geometry and skin tone and their effect on the energy density fluence distribution within tissue. Monte Carlo modelling is one of the most widely used stochastic methods for the modelling of light transport in turbid biological media such as human skin. Using custom Monte Carlo simulation software of a multi-layered skin model, fluence distributions are produced for various non-ionising radiation combinations.
Fluence distributions were analysed using Matlab mathematical software. Meaning little additional penetration is achieved with larger spot sizes.
Fluence distribution within tissue and thus the treatment efficacy depends upon the illumination geometry and wavelength. To optimise therapeutic techniques, light-tissue interactions must be thoroughly understood and can be greatly supported by the use of mathematical modelling techniques. Human skin is the interface between man and his environment. One of the environmental factors it has to deal with is ultraviolet UV radiation. Ultraviolet radiation may cause negative effects such as erythema, skin ageing and skin cancer.
The upper layer of skin, the epidermis, acts as a natural UV filter and may thicken or develop a stronger pigmentation as an adaption to excess UV exposure. On the other hand, UV radiation induces photo production of previtamin D 3 in the skin and thus provides the major natural source for vitamin D 3 for humans.
