Laser specialist Kevin Williams presents an overview of recent technological advances in intense pulsed light (IPL) systems.
Having worked within the industry for over 20 years, I have witnessed firsthand the evolution of laser and IPL technology, and their impact in the medical and aesthetic community. The first IPL systems were launched in the mid-'90s to treat vascular lesions. Nowadays, IPL systems can be used to treat a variety of aesthetic and dermatology skin conditions safely and effectively.
How IPL Works
As with lasers, the interaction of IPL sources with tissue is based on the principle of selective photothermolysis, a theory first introduced by Dr. Rox Anderson et. al. in the late '80s. The theory concluded that different skin targets require different wavelengths or bands of light, different amounts of heating times, and varying amounts of energies. The wavelength or band of light not only needs to be preferentially absorbed in the target chromophore but reach the correct depth as well.
Current Control - A New Way To Change The Wavelength
Interchangeable filters (Figure 1) are used on most IPL systems to cut off wavelengths of light below or above their value, while other manufactures require the whole handpiece to be changed or the handpiece and some filters to be changed.
Interchangeable filters allow for a set range of light to be delivered to reach varying depths and target chromophores. The light emitted passes through, and the filter 'cuts off' undesired wavelengths and maximizes the pass-through of the chosen ones. This is particularly useful if a provider wants to treat someone with different indications, such as both facial redness and pigmentation.
Figure 1: Interchangeable Filters
I have used both types of IPL, and there are advantages and disadvantages to both. I have found that performing multiple passes at different depths to improve the clinical outcome is easier with interchange filters. The downside is that they are much more prone to damage.
A new and innovative way, which adjusts the output band of light, is by an electronic current control within the main body of the system itself. You will see from the diagram below (Figure 2) that the wavelength remains the same, but the actual shape of the output changes. This shape-shift changes the concentration of the light energy and, in simplistic terms, allows for the bulk of energy to be delivered at different peak outputs.
Figure 2: Current Control Wavelength
The xeo limelight handpiece (Figure 3) allows me to change the peak absorption to 580nm, 560nm, or 520nm based on the program I select. This versatile approach enables the system to be extremely user friendly and reduces the running costs that are often associated with interchangeable filters or the expense of purchasing several handpieces. It provides me all the benefits of a quick change in wavelengths without the risk of damage to the filter or handpiece.
Figure 3: xeo Limelight Handpiece
Another technology that is relatively new to IPL systems is the Single Band (SB) filter (Figure 4). This filter cuts off the lower and higher bands and, more importantly, red and IR light that is highly absorbed in melanin. This allows all of the energy to be delivered in a single band of green/yellow light, which is highly effective in targeting blood vessels. Indeed, it's like combining a frequency-doubled Nd:YAG laser (532nm) and a Pulsed Dye Laser (585/595nm). An SB filter is also useful when treating very light superficial pigmentation, and in my treatment experience to date, I have seen a significant improvement with this technology.
Figure 4: Output of a SB Filter
This is a typical result you can achieve using a modern IPL with a Single Band filter. Before and one month after one treatment using the xeo IPL by Cutera, Inc. with the following parameters: Accutip SB Filter, Program A 14J/cm².
Before and one month after one treatment using the xeo IPL by Cutera, Inc. with the following parameters: Limelight handpiece, Program B 14J/cm².
Intense pulsed light technology is highly versatile, safe, and effective for the treatment of vascular and pigmented lesions, hair removal, epidermal and dermal atrophy associated with photoaging, as well as acne and rosacea. Newer innovations such as Current Contol Wavelength and Single band filters have optimized the energy and light delivery of IPLs expanding the capabilities and treatment efficacy. Disclosure: Kevin Williams is the chief technical officer at Wynyard Aesthetics Academy. AP003461 rA