The answer to this question is very simple – TEMPERATURE!! Think about what we’re trying to do when treating hair, blood vessel or benign pigmentation. We are trying to ‘kill’ certain cells, using heat. That’s why we fire laser light energy at them. We’re trying to force them to absorb that light energy, convert it… Continue reading What is the key to success with laser/IPL treatments?
Author: Mike Murphy
I started in medical lasers in 1986! I have been involved in clinical research, medical laser and IPL development, sales and marketing across Europe and South East Asia, business start-ups, theoretical research into laser-tissue interactions, training course development, writing articles for peer-reviewed journals and industry magazines. I am currently the Chairman of the Association of Laser Safety Professionals.
Not all hair removal lasers and IPLs are the same!!
I’ve been doing a lot of work recently, looking at how lasers and IPLs differ when considering hair removal. They’re all different!! In various ways… Comparing diode lasers with Nd:YAG lasers with alexandrite lasers is like comparing chalk with cheeses. It is quite tricky trying to compare these devices properly. Add in IPLs and it… Continue reading Not all hair removal lasers and IPLs are the same!!
SHR – how good is it?
OK, this might cause a bit of controversy! As many of you know, I’m not a fan of the SHR technique. Why? Because I think it’s very inefficient in the hair removal process. So I made this little video to explain my thoughts on this technique. If you have other thoughts and ideas, please let… Continue reading SHR – how good is it?
“Pain free” hair removal. Is it real?
We often hear, these days, about “pain free” hair removal, with various lasers, usually diodes. But, is it true? Well, let’s look at this more closely… The aim with laser, or IPL, treatment of hair is to induce enough heat in the stem cells that stimulate hair growth in the follicles. To do this, we… Continue reading “Pain free” hair removal. Is it real?
Selective Photothermolysis – an in-depth explanation
Back in 2016 (I think) I gave a talk to the American Society of Lasers Surgery and Medicine about the theory of Selective Photothermolysis. This is the theory which underpins all of today’s photothermal laser/IPL treatments. In this talk I discuss the idea behind thermal relaxation time and how it ‘fits’ with treatments. In fact,… Continue reading Selective Photothermolysis – an in-depth explanation
Laser/IPL Hair Removal – How many follicles do we kill each treatment?
All hair follicles grow according to a cycle – ‘anagen, catagen, telogen’. The follicle germative cells promote anagen hair growth at consistently regular intervals resulting in periods of active growth, followed by inactivity. The duration of these periods depends on the which part of the body is being considered. I created a computer model to… Continue reading Laser/IPL Hair Removal – How many follicles do we kill each treatment?
“The hairs grow back after the treatment…”
I often see laser/IPL users making comments like “the hair grows back after a treatment…”, or something similar. When we treat hair with light energy, we cannot expect to kill all of those in the anagen phase (laser/IPL light can kill only the anagen follicles). In reality, most operators might kill between 50 to 80% of… Continue reading “The hairs grow back after the treatment…”
More on the ‘best’ intervals between laser/IPL hair removal sessions…
Choosing the ‘best’ time between laser/IPL hair removal sessions is not simple. It depends on the hair growth cycles of the hairs we are targeting, which is not the same across the body. That means that we need to consider the body area when deciding how long to leave between sessions. We can only target… Continue reading More on the ‘best’ intervals between laser/IPL hair removal sessions…
What is the ‘best’ interval between hair removal sessions (after treatment by lasers or IPLs)? Part 2.
I wrote a blog post back in September 2021 discussing my thoughts on the how to determine the optimum interval between laser/IPL hair sessions. It proved very popular amongst my readers. But, as soon as I posted it I began to doubt my own conclusions. Back then I suggested that we should wait for an… Continue reading What is the ‘best’ interval between hair removal sessions (after treatment by lasers or IPLs)? Part 2.
How strongly are different laser wavelengths absorbed in melanin and blood?
These days we use a wide variety of lasers and IPLs to treat various targets in the skin. Two major targets are hair and blood vessels. But how much of the laser/IPL light is actually absorbed by these targets? Using data from two very clever scientists (Steve Jacques and Scott Prahl) it is relatively easy… Continue reading How strongly are different laser wavelengths absorbed in melanin and blood?
Mike Murphy's Blog 