Ultra VPL™ Advantage

What is micro pulsing and why is it better than a single pulse (the Ultra VPL™ advantage)?

The purpose of any photo-thermal treatment is to raise the temperature of the target to a critical level, usually about 70°C, while making sure the surrounding tissue, and in particular the epidermal melanin layer, stays at a safe level (usually less than 45-50°C).

The majority of any visible light which falls on skin tissue is absorbed by the melanin in the epidermis, the melanin in the hair shaft and red blood cells (red blood cells absorb mainly blue, yellow and green light).

For discussion, we’ll use hair removal as our target example.

To achieve hair follicle destruction, we need to heat the hair shaft to well over 70°C while leaving the melanin layer in the skin below 45-50°C. The light, which reaches the base of the hair shaft, has to pass through the skin first, so it is not possible to deposit energy into the hair without also heating the skin. The ‘trick’ is to take advantage of the cooling characteristics of the two structures.

The hair shaft has a dense concentration of melanin, but is only loosely connected to the surrounding tissue, so it takes a long time for heat to diffuse away. On the other hand, the skin has a broad, flat bed of melanin around the dermal/epidermal junction, which is quite thin and well connected to bulk tissue, blood vessels and the surface, so it cools much faster.

If we put in a short burst of light energy, both the hair shaft and the skin absorb some of the energy and their temperature goes up by a few degrees. Immediately after the pulse, both structures start to cool, but the hair shaft cools much more slowly. If we wait just a few milliseconds the skin melanin temperature can fall by about half of the amount it rose during the pulse, while the hair shaft temperature falls by less than 10%.

If we fire another pulse, the hair and skin raise by another few degrees, and in the next break the skin can again return closer to its original temperature while the hair loses about another 10% of its total temperature rise. Now the skin is only a few degrees hotter than it was, but the hair has risen nearly twice as much.

With a timed sequence of four or more pulses, it is fairly easy to achieve the necessary rise in the hair shaft without stressing the skin. The stored heat in the hair shaft then diffuses out slowly, killing the nearby layer of cells in the follicle and bulge.

The sudden skin temperature rise is what causes the mild sting associated with an IPL pulse, and the associated risk of hypo or hyper pigmentation. It also reduces client discomfort. Many of our clients, who have tried other IPL machines, and Laser, report significantly less sensation at the same levels of treatment. This greatly improves treatment compliance and client return rates, and also reduces the possibility of side effects.

With the ability to add more pulses to the sequence (up to 15), and increasing the delay between the pulses (up to 20 milliseconds between each pulse) so as to provide a thermo cooling effect on the surface, this method not only protects the skin, but it allows the effective treatment of even heavily pigmented skin types.

This same principle can be applied to all Ultra VPL™ treatment targets, and as explained, is safe for all skin types.

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