Non-Surgical Body Contouring: Introduction of a New Non-Invasive Device for Long-Term Localized Fat Reduction and Cellulite Improvement Using Controlled, Suction Coupled, Radiofrequency Heating and High Voltage Ultra-Short Electrical Pulses.
Intense pulsed light (IPL) technology has become a common tool in medical aesthetic practices for skin rejuvenation. The popularity of IPL technology has increased because of its simplicity, low cost and versatility, allowing for treatment of a variety of vascular and pigmented lesions. The broad spectrum of IPL covers the visible and near infrared spectrum and can be easily adjusted for specific applications by using filters and optimizing lamp parameters. The spectrum of IPL may be used for treatment of pigmented lesions with different levels of aggression; it includes multiple peaks of hemoglobin absorption, and penetrates into the skin down to a few millimeters at longer wavelengths.
The other advantage of IPL is the variability of the pulse width in a relatively broad range from a few milliseconds up to a few hundred milliseconds. Energy can be delivered in a single pulse or in a train of pulses.
Even the first IPL had multiple filters and a sophisticated pulse structure . Future efforts were directed to the optimization of broad spectrum filtering, trying to reach the efficiency of pulse dye laser for treatment of superficial vascular lesions . The treatment results were comparable but at significantly higher fluences than with PDL. These results can be interpreted in two ways: The IPL, even after optimization, has less treatment selectivity, or peak power of the IPL is lower than one of the laser.
The treatment of vascular and pigmented lesions is based on principles of selective photothermolysis suggested by Anderson and Parish :
- Light penetration depth should be high enough to reach the treatment target.
- Light absorption by the treatment target should be higher than by surrounding tissue
- Light should be delivered in pulse manner and pulse duration should be shorter than thermal relaxation time of the treatment target
The authors of  tried to demonstrate that long pulse durations of up to 400ms can be as effective as a short pulse, but this concept has proven relevant only in particular scenarios where the “heater” and “real” targets are dimensionally optimized for “very” long pulsed applications. On the contrary, the home use IPLs with sub-millisecond pulses demonstrate reasonable efficiency with fluences less than 4 J/cm2. 
Higher peak powers allow for the following potential treatment benefits:
- Coagulation temperature in the target can be reached at a lower fluence.
- Higher selectivity.
- Smaller targets can be treated.
This article is intended to demonstrate efficiency of the IPL device which is designed to provide the highest peak power and shorter pulse duration for treatment of vascular and pigmented lesions.
Pulse width and its relation with target- specific thermal relaxation times (TRT) is one of the critical elements of selective photothermolysis .
Where d is size of the treated target, A geometrical factor (A=16 for cylindrical target and A=4 for planar target), α is diffusivity of
tissue and can be estimated as one of water (α~10-7 m2/sec).
If pulse width is longer than TRT of the target, a significant part of the energy is dissipated from the target to the surrounding tissue. Figure 1 shows temperature distribution for the pulse with duration of 0.3 of TRT and three times longer than TRT.
One can see that at the same applied energy, the peak target T can be 2X that associated with the longer pulse. Consequently half of the energy is sufficient to reach the T for coagulation.
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