It’s very clear to me that this subject is quite badly taught out there. Many of my clients tell me stories of what they’ve been taught, which are just clearly absurd or ridiculous. Things like ‘increasing the fluence’ with each treatment session. Or ‘matching the pulse width with the size of the hair’ – these are just nonsense.. The physics makes that very clear.
So in this short summary I’m going to explain some of the real basics behind this treatment.
- The choice of wavelength is unimportant for the successful removal of dark hair. However it does become important when considering the skin tone. And this is where ice cooling becomes very important. I’ll discuss that later.
- The choice of pulsewidth or pulse duration is also unimportant for the vast majority of cases. I hear people being taught to match the pulsewidth with the diameter of the target hairs. This is wrong. We are not trying to kill the hair. We are trying to kill the hair follicle. Follicle dimension is not equal to the hair dimension. In fact, the real target appears to be the dermal papilla at the base of the follicle. Whilst the dimension of the DP is close to the diameter of the hair, that is not a critical factor.
- Spot size is not important once it exceeds about 11 mm in diameter. Above that size there is no gain to be had in terms of penetration depth. The physics is crystal clear on this.
- Whether you choose the stamping technique, the sliding or gliding technique, or the stacking technique is also not so important. What is more important is the fluence applied.
- Fluence is king! It is the fluence which drives the whole process and determines whether you will be successful or not. It also determines the total number of sessions required. A low fluence merely pushes up that number of sessions. Please don’t increase the fluence with each session – that’s just nonsense.
- The time interval between repeat sessions is also very important. If you use a short time interval, such as four weeks, you will increase the total number of sessions (simply because there will not be a high number of target follicles). In that respect it is similar to fluence. Hence if you use a low fluence and short time intervals, then the total number of sessions will be large. Different body sites require different intervals.
- Skin cooling is vital. We cannot rely on the technologies to provide sufficient skin cooling – they are simply not designed to do that. So we must employ external methods such as ice or air cooling or cryogens. Skin cooling not only reduces the pain sensation but also epidermal and upper dermal damage. My preference is ice cooling. It is by far the most efficient technique.
- Be careful not to apply ice packs straight from the freezer to the skin. This will inevitably induce ice burns. Allow the ice pack to melt for 2 to 3 minutes before wrapping in cling film or paper or a towel and then apply it to the skin surface.
- Tell your clients/patients that the pain from the ice is temporary. However the pain from a burn can be permanent and may lead to scar formation.
- Deeper hair follicles tend to produce larger diameter, and darker, hairs. So you can gauge the depth of the target follicles by the thickness of the hair. You should then match your fluence accordingly. Deeper follicles require higher fluences.
- Do not treat over tanned skins. A tanned skin is already a damaged skin. Don’t increase that damage by applying light energy.
- Do not treat near tattoos, or unknown pigmented lesions. Covering them with white paper or tape makes very little difference since scattering within the dermis may potentially cause the energy to reach those targets (if you are too close!). In fact, covering a tattoo or a pigmented lesion with paper or tape might even increase the potential for damage since the light cannot escape above them.
- The number density of nerve endings at the skin surface varies enormously across the body. So some areas will generate much more pain than others merely because of this number density.
- Shaving before a treatment is a good idea. It reduces the total amount of plume which may enter the atmosphere of the room. You really don’t want to be breathing in that plume. Make sure you take precautions such as an air filtration unit or masks (FFP2/3, K95/99).
- Waxing, threading or some other form of depilation prior to treatments may actually be a good idea. I am working on this subject at the moment and plan to publish something soon.
These are our top tips for laser/IPL hair removal. Some of them will undoubtedly contradict what you have been taught so far. You have been taught wrongly. It seems to me that many of the trainers out there are not well-versed enough in the biophysics of the treatments, and they are merely repeating the same incorrect messages they were taught.
Destroying hair follicles using light energy is not actually that difficult, as long as you understand what you’re doing and why.
This is what we teach at DermaLase.
Ciao for now,
Mike.
And in my book…
Plus we sometimes chat about this in our podcast too!
Apple Podcasts – https://podcasts.apple.com/…/lasers-in-skin/id1790635555
Spotify – https://open.spotify.com/show/6qWY0GOunSjOvYzNmEPeUX
Audible – https://www.audible.co.uk/podcast/Lasers-in-Skin/B0DT4DBP32
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