Page 90 - Chapter 3 - Laser/IPL Hair Removal

Chapter 3 – Fundamentals of Laser/IPL Hair Removal 2nd Edition
However, some of the follicles which had been in anagen will now be in catagen or telogen. During the second treatment, some of the anagen follicles will be destroyed. A short time after the second treatment we can see the remaining follicles, in various phases...
The ‘trick’ is to treat each area when the maximum number of anagen follicles are present. This can be difficult to determine since we can never know which phase the follicles are in at any one time. However, a good method is to ask your client/patient to return for subsequent treatments when a significant amount of hair is clearly growing. That way, you can be sure of treating many anagen follicles.
‘Re-growth’ of hair
Many laser operators complain of ‘re-growth’ after treatment sessions. Their patients/clients return pointing out “new” hair growth. But, this is often wrong!
Language is very important here!
When we treat hair with light energy, we know that we can only kill those follicles in the anagen phase. In fact, we now know that only around 50% of those anagen follicles are susceptible to these treatments.
Inevitably, this means that quite a significant amount of the follicles we treat will grow back – often finer and lighter in colour. Those are the follicles which were not irreversibly destroyed previously. So, those hairs will “re-grow”.
During the intervening period, some of the previously catagen and telogen hairs will now come back into anagen. These follicles will grow “new” hairs, which were not visible in previous treatments. These are NOT the same as re-growing hair – they are ‘new’.
This distinction should be pointed out to all patients/clients, as they often do not understand this difference.
We should also point out that “permanent” removal does not mean “100% clearance”. It means that ONLY those follicles which are properly treated cannot regrow. But, any follicles which are not completely denatured can grow back - usually finer and lighter. These follicles tend to be in the ‘stun’ zone (see ‘The Kill-Stun-Null Zones’). They can be successfully treated again, usually with higher fluences.
Plus, dormant follicles can grow at any time. These are unaffected during light-based treatments.
All of these issues should be explained to all new patients/clients, to increase their understanding and set realistic expectations.
________________________________________________________________________ 90 Chapter 3, Ed. 2.0 Laser/IPL Hair Removal
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