Palomars response to the Dog & Lemon IPL Guide.

A “practical, unbiased, objective” response to the published materials authored by Paul Kadar of

The choice of the words “practical, unbiased, objective” in the title are borrowed directly from the opening pages of the review by Mr. Kadar. His 41 page review is neither practical, unbiased nor objective and it contains so many inaccuracies that one would question whether it is of any value what-so-ever. Admittedly, I do not know Mr. Kadar, nor his qualifications to analyze competing technologies. I will address, page-by-page all of the inaccurate factual pronouncements in his paper, so I will refer to this comments by making references to his original comments. To be fair, he does make some valuable contributions for understanding how to optimize IPL technology, however, his clear bias toward the Sciton BBL system completely cloud his judgment and produce some very “fuzzy physics”.

Page 6 – Obviously, the MediLux has been a popular IPL in many parts of the world, however, not in New Zealand or Australia. We sold none in these two countries. I can only assume that he is referring to the StarLux and I will go forward using all references to the StarLux, not MediLux. However, he therefore gets many of the specifications confused between the two units.

Page 7 – Uniform Delivery - Many of the points made in the first few paragraphs are correct. Many poorly designed and constructed IPL heads have a very poor distribution of light throughout the optical waveguide to the tissue. He is correct in the assessment of the temperature rise within the hair follicle and that if the temperature is insufficient to completely damage the hair, the result will be a thinner, finer hair, which is in fact a recurring problem for most hair removal devices. He is also correct in saying that poor spatial distribution across the sapphire or quartz waveguide will necessitate larger more overlapping from pulse to pulse, and this again has its’ own set of problems, including adverse side effects from too much energy absorption by the epidermis. Using the term “perimeter loss” as Mr. Kadar employs it, necessitates a better explanation of what cause it. His reference to the “inverse square law” is interesting and would be useful if we were discussing the amount of sunlight hitting the various planets in the solar system, but it is not relevant at all when dealing with a few centimeters close to the skin. His reference assumes that no manufacturers do anything to the pulse of light in terms of controlling the direction and focus of the output. If the 20 J/cm2 were a point source of light and you doubles the distance to the observer , it would indeed decrease by the distance squared. However, all IPL manufactures use some type of reflector system to directionally deliver as much light as possible through the waveguide to the tissue. It is not the difference in the distance from the lamp to the edge of the waveguide versus the center of the waveguide that matters, (even if it did, this is a simple geometry problem, not an Inverse Square Law problem) it is a problem of the optical reflector design.

So, let’s look at Mr. Kadar’s solutions to minimizing “perimeter loss”.

1. Small Surface Area of the Head – He is correct that if you make the tip small, you usually get a better homogenized beam, but the real reason that the tip (size of the surface area of the waveguide) is small is due to the lack of energy produced by the flashlamp in the first place. The Syneron ELOS – Aurora or E-Light are perfect examples of this. The only way they can show a high output fluence to match other systems is to design a small spot size hand piece. You may also notice that physically small hand pieces, although they appear small and therefore are easier to manipulate on the skin also have physically small flashlamps. There is “no free lunch” in this area. The length and cross-sectional area of a flashlamp will dictate the energy output in all practical areas. If I choose to use a small lamp and electrically “pump” it very hard, I can produce high output energies, but I will kill the lamp very quickly.
2. Photon Recycling – I would absolutely agree that Mr. Kadar is clearly no “rocket scientist”, but his analysis of photon recycling is so incorrect, that I would have to doubt that he has any understanding of science. First of all, just to straighten out the misinformation, light travels at 300,000 m/sec (186,000 miles/sec). If the distance between the flashlamp and the skin is 3 cm (light travel 30,000,000 cm/sec) and the pulse of light is 30 milliseconds long, a photon of light could travel approximately 1,000,000 cm in that time. So, if the distance to the skin and back to the flashlamp is 3 cm each way, you could at least get 150,000 oscillations or cycles at a minimum. Therefore the statement that the “fluence will have all but petered” is purely ridiculous. Photon recycling (developed and patented by Dr. Rox Anderson at MGH/Wellman Labs of Photomedicine and licensed and implemented by Palomar) is designed to recapture as much scattered light from the various surfaces and structures in the skin whenever those photons scatter back into the hand piece. Much light is still lost due to scattering which is not perpendicular to the skin (this is the flash that you see with you eyes). There are some basic principles that are necessary for photon recycling to work. First, the waveguide must be in direct contact with the skin. Floating a hand piece tip in a thick ultrasound gel does not work. Secondly, the reflectors in the hand piece must be specifically designed to focus the IPL light toward the skin and maximize the amount of deliverable photons of light to the skin and thirdly, the tip of the waveguide must be designed to minimize any light leakage laterally from the tip. The Palomar StarLux meets all three criteria better than any other system.
3. Long Light Guide – Mr. Kadar is correct that a long waveguide does homogenize the light passing through the waveguide and consequently, the output pulse of light is very uniform across the entire surface of the waveguide. And in fact he is also correct that some light is lost in the homogenization process, but if the reflective surfaces are properly designed and all surfaces are coated properly with the correct reflective coatings, these losses are minimized. However, where Mr. Kadar’s objective review falls short is in recognizing that the Palomar StarLux produces the highest output fluences available in the industry even with these long waveguides.
4. Twin Flashlamps – Twin flashlamps can be of value in an IPL system, but not for the reasons Mr. Kadar states. If you assume that there are no reflectors at all in an IPL head, then indeed, one lamp might be in the shadow of the other lamp, but his assumption makes no sense at all if the hand piece is built with parabolic reflectors surrounding the foci of the lamp’s location. Simply put, when you turn on the head lights of your car, why does the light travel so far in a relatively collimated beam? It is because the mirror surrounding the bulb in the head lamp is a parabola. He is also incorrect when discussing the side-by-side configuration of a dual lamp system. This design also works well and helps produce a more uniform beam. However, as stated above, properly designing an IPL head solves all of these problems. Mr. Kadar’s clear bias rings through on this one when he refers to the “essential, over-under twin flashlamp design of the Sciton BBL. The only thing that twin flashlamps buys you is that a somewhat lower flashlamp pumping energy is needed for each flashlamp so you can get long lamp lifetimes, but we will discuss this later.

Head Size – Again, Mr. Kadar begins correctly and his first few paragraphs are correct in reference to scattering deeper into the tissue. Larger spot sizes permit deeper scattering into the tissue and better results, particularly for hair removal. However his statements in the lower half of page 10 are incorrect. If you have the same fluence (Joules per square centimeter), the larger spot size will give you better and deeper scattering, you don’t need three times the energy if the spot is three times larger if you start with the same fluences. The larger spot size hand piece will necessarily put out more total energy to achieve the same fluence, but fluence is fluence, period. Clearly, the last statement on the page has absolutely no scientific support and is just another commercial comment for the Sciton BBL system.

Variable Temperature Control – At least in this section, I do have some degree of agreement with Mr. Kadar. Cooling the skin is very important for all IPL applications, some more so than others. I also do agree that IPl’s with no cooling can be safe and effective, but the procedures are riskier, so if some one says that cooling is unnecessary, they are mistaken. His chart is incorrect again, because the Palomar MediLux does not have integrated cooling, but the StarLux does. In fact, Palomar holds some of the dominant patents in cooling technology. Variability in the temperature control is nice, but he avoids the more important considerations of cooling. Temperature control or the absolute low temperature setting are of no use what-so-ever if you can’t effectively get the heat out of the skin. In other words, many IPL’s that have integrated cooling built into the system have inadequate overall cooling to constantly extract the heat from the skin. It is a basic Law of Thermodynamics that the extraction of heat from is a rate equation. You must have a thermal mass large enough (large piece of sapphire, not quartz) that has proper contact cooling with it and has direct contact with the skin as well as an adequate chiller inside the basic unit. All too often, as a procedure starts, the tip of an IPL is cold and then as each light pulse is emitted, the tip heats up until the skin gets burned because there is no longer any effective cooling. Only the Palomar StarLux has this degree of efficient, effective long lasting contact cooling. So it is not the temperature to which the hand piece cools that really counts, it is “how well does it stay cold during a lengthy procedure that counts”.

Long Pulse Widths – for the sake of brevity, I will not try to correct some small inaccuracies in this section, it is basically correct. His chart is incorrect because again he refers to the Palomar MediLux, instead of the StarLux and he refers to the pulse durations for the Palomar system as 400 msec. It is true that the StarLux can extend the pulse duration to 500 msec, but for all practical purposes, we very rarely use any pulses longer than 100 msec.

High Fluence – I find it very interesting that in this section, Mr. Kadar retreats from the issue of directly comparing fluences of various systems. There is plenty of truth to the statement that no two systems are designed the same or produce the same outputs, so the fluence of one system may not actually be directly comparable to the fluence of another system from a clinical evaluation point of view, but in this area where the BBL produces only a modest output fluence, Mr. Kadar simple says it is not really important. I doubt that many others will agree with this.

Pages 13 and 14 – These pages deal with Clinical Training issues, which although these are very important, they are not unique to a machine or device, so I will skip these.

Integrated Contact Cooling – His synopsis is basically correct although he does not explain how a system maintains a constant temperature.

Filtering – Almost all IPL systems use water to cool the flashlamp to prevent it from exploding (which would be an undesirable operating characteristic). Therefore, all IPL wavelengths above 950 nm are at a minimum. The normal operating output of a xenon arc lamp is about 380 nm to 1,400 nm. Even without the water cooling and consequential absorption of the long wavelengths by water, there is very little energy available from the lamp at the very long wavelengths.

Therapeutic Dose – Again, Mr. Kadar begins correctly but his logic and assumptions digress rapidly. His Non-Square Wave and Square Wave descriptions are basically correct and the consequences and potential side effects of the Non-Square Wave pulse are also correct. However, at Palomar, we maintain that neither of his pulse profiles is very good and the only really “Square Wave Output” is one that does not that the series of 10 or so short pulses (which can also be very dangerous). Our Smooth Pulse design (also patented) is truly a square wave profile and produces the safest, most predictable results. Mr. Kadar’s chart on page 17 is completely incorrect. All Palomar systems produce a ‘smooth pulse profile” and always have since the EsteLux was introduced in 2001. Our advanced power supply technology permits considerable variation in the pulse format if we so desire to change it.

Sapphire vs Quartz – This issues Mr. Kadar brings up regarding the difference between sapphire and quartz are small concerns. The major difference deals with Thermal Conductivity. Quartz (similar to window glass) is an insulator. It has always been used as an insulator. On the contrary, sapphire (and for that matter - diamond) is one of the few crystalline materials that have the same thermal conductivity properties of a metal. So the heat transfer needed for effective contact cooling can only be accomplished using sapphire as the tip of the hand piece. Again, Mr. Kadar invents his own statistics regarding which manufacturers use which materials. Palomar was the first to use Sapphire and has never used anything but Sapphire in all of our IPL hand pieces.

Again, his discussion of training and adverse reaction reporting, although important, are unique to different distributors, etc.

Repetition Rate – Most of what he has said here is OK, some minor problems, but his explanation of the capacitor circuits is satisfactory. One major addition is needed. The repetition rate is also a function of the fluence for each pulse. The more energy that needs to be discharged from the capacitors to the lamp means the more time that is required to recharge the capacitors. So operating at high fluences means inherently slower repetition rates. Therefore, the chart on page 21 should be amended because the Palomar StarLux operates at 2 Hz, not 1 Hz. The StarLux 500 System is now 70% faster than the original StarLux so even at higher fluences, the rep rates are higher.

Range of Wavelengths – (page 22). Again, Mr. Kadar assumes a very simplistic approach to wavelength selection. The reason manufacturers like Palomar design specific wavelength ranges for specific application hand pieces is to maximize the effects of the individual hand pieces for the specific treatment protocol. By using dual wavelength filtration, (both absorption and dichroic-relecting filters), we can make an IPL hand piece operate more like a specific laser wavelength. Therefore, the chart that Mr. Kadar shows is incorrect for the Palomar systems. In addition, what Mr. Kadar does not understand or make the effort to understand (from his unbiased point of view as an expert) is how the Cutera system works (I presume the CyDen iPulse works the same as the Cutera system, but we don’t see that system here in the US, so I can’t absolutely make that statement).

Control of the discharge temperature of the flash lamp determines the emission spectrum of the output. The discharge temperature is often called the “color temperature” of the lamp. Short pulses, with the same output energy, produce a higher color temperature because of the higher peak power needed to create an output pulse with the same energy as a pulse with a longer pulse duration. Lengthening the output pulse, with the same output energy, lowers the color temperature of the pulse and shifts the natural emission spectrum of the output to the “redder” part of the spectrum. Cutera claims approximately 70 – 100 nanometers of wavelength shift from the yellow/red area to the redder wavelengths. They also claim that this is enough to produce selectivity in their treatment protocols to treat darker skin types. All Palomar systems have had this power supply design feature from the first EsteLux units in 2001. This is a “patented” technology that is a standard Palomar feature. However, even though the wavelength shift is helpful, Palomar does not believe that this shift alone provides enough selectivity or safety for the each treatment protocol. In fact, Palomar now offers 7 different IPL hand pieces which all provide over 100,000 shot warranties. Then there are an additional 5 laser hand pieces and 2 Halogen lamp based hand pieces for deep heating. So the chart on page 23 is also incorrect, but the rest of the page is acceptable.

Pages 24 – 26, while obviously relevant to the user, is completely dependent on the distributor or the manufacturer. As in previous charts, Mr. Kadar does not accurately represent the amount of support information committed to the end user by Palomar.

Treatment Head Replacement - When a single treatment head is used for all treatments by the interchange of slide in filters, the consumption of that single head should be fairly fast. In addition, if there is a malfunction of that single head, the user is completely out of luck and must shut down their entire operations until a replacement is made. Palomar’s plan has always been to optimize the hand piece for the application. The availability of individual hand pieces to optimize the treatment protocols for each application is our most important goal, but this also has a very positive operating cost savings as well. Each IPL head is warranted for a minimum of 100,000 pulses (or two years – which ever comes first), so with a standard system consisting of a Lux G, Lux Y and Lux R hand pieces, you have over 300,000 pulses guaranteed and you optimize the output parameters as well.

Profitability Analysis – This section is based on so many inaccuracies previously mentioned that it is impossible to even comment on it. With over 5,000 IPL systems sold in the last 5 years, I can absolutely assure any prospective customer that our customers earn a very substantial return on their investments. Clearly, how a user operates their own business will ultimately determine the degree of success. A completely fabricated chart of ROI will not even remotely provide the answer.

Page 36 – just completely incorrect, not even the system we sell in N.Z and Australia. This page is just further evidence of the very poor quality of this analysis.
Further discussions at the end of the analysis are also incorrect for many of the above mentioned reasons. His beginning summation of platform technologies is incorrect again so I see no possibility that any further discussions by Mr. Kadar will have any merit as well.