Page 165 - Chapter 3 - Laser/IPL Hair Removal

Chapter 3 – Fundamentals of Laser/IPL Hair Removal 2nd Edition
Figure 95 - Reduction in the number of hair follicles after each treatment session
In the above graph (Figure 95) we can see the percentage reduction of all hair after each treatment session. After the first treatment we can see a total reduction (of all hair) of around 27%, followed by 21, 19, 12 and then 6%. The final treatments only remove around 3% each!
It really is a case of 'diminishing returns' with each treatment. There are fewer anagen follicles available each time a patient/client comes back, so each treatment attacks a smaller number of anagen follicles.
Summary
As we can see, the reduction of hair following laser/IPL treatments is not obvious. Assuming the worst possible outcomes in each treatment, we can see that the loss of hair follicles drops by around 20 to 27% for the first three sessions, then drops to around 12% and below. Just over two-thirds of the hairs (67%) are removed in the first three sessions.
But, the upper graph shows that the number of anagen follicles may not change by that much over the first three or four sessions. This can be a bit irritating when treating clients/patients, but you should explain that they are seeing 'new' growth alongside 're-growth' (from those follicles you didn't kill previously).
________________________________________________________________________ 165 Chapter 3, Ed. 2.0 Laser/IPL Hair Removal
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