Bringing up overlapping

Hair Removal Methods Laser hair removal
1

Hi,

Although I might have visited this site once in a while in the past, I’ve only recently been exposed to this site, so I can’t say: I’d been a avid follower of the boards and I know pretty much what discussions has been held here. However, the readings here I have done lately convinces me that I am right about the following:

Overlapping is one of the key elements in Laser Hair Removal (LHR) and it is frequently mentioned on these boards too, but superficially. Therefore, in this thread, I want to get a little more into detail.

If we confine the knowledge with the limits of this froum, there are concepts of

  • %10, %20 (given credit as leaving no gaps), %30 overlapping
  • enough overlapping
  • double zapping
  • overlapping very closely
  • no overlapping

In many circumstances, it is stressed that overlapping is very important, and when it comes to beard it is the most important parameter to avoid patchiness. Consensus is that it has a vital role on patchiness generally on all body areas.

On the other hand, some people claimed that overlapping in the least possible manner, is disadvantageous than no overlapping: it can lead to tissue damage, and regardless of damage it is not wise to overlap in a very dense follicle setting.

One person, specifically me, said the peak energy is absorbed from the center of the spot on the skin, and if the laser beam is penetrating deep enough comparable to the spot size radius this may be a parameter that should be taken into account in overlapping.

As being a person treated with a LHR machine which had an applying head with a skin touching square glass piece through which the system shot 9 (3x3 = a total of 3 rows each having 3 pulses) consecutive circular spot pulses, and one person saying he was treated with Lightsheer with 12mm2 square prism so there was no need for overlapping, I wonder how it is ensured all the subject area is covered.

As for the overlapping techniques, one made a comment about a “constant glide overlap” method.

Upon provided with different concepts and ideas, I began to think on overlapping: what really it is. I mean, what does %10, enough, or even very closely overlapping mean at all? There is no easy answer. Like told above, patchiness can be controlled under superior overlapping. Can it be really?

In order address all these issues, I ask everyone about the answers. As to keep ambiguity low, I also put some figures that may be treatment scenarios. They are chosen by me as there may be many other ones; if you have in one mind, let me know. Which one do you think is the best one? And, why do you think so?


This is to compare all 7 patterns. A circle accounts for a laser spot. Does not it seem, whatever pattern we choose theres is no way of applying uniform energy on skin?


In order, 1st, 2nd, 3rd, and 4th patterns.
1st p: 2 energy levels. (P, 2P)
2nd p: 2 energy levels. (P, 2P)
3rd p: 4 energy levels. (P, 2P, 3P, 4P)
4th p: ~3 energy levels. (2P, 3P, 4P)


5th p: 3 energy levels. (2P, 3P, 4P)
6th p: 4 energy levels. (P, 2P, 3P, 4P)
7th p: 3 energy levels. (2P, 3P, 4P)

2

Generally, overlapping by 10% or so should be enough and won’t be destructive to the skin (laser is attracted to the hair, not the skin, so if the right settings are set, it shouldn’t matter anyway).

Keep in mind that there are various machines with various heads, some square, some circular. GentleLASE for example has sort of a round head, so overlapping is especially necessary in order not to miss areas.

Settings also matter since they determine how deep the laser penetrates. On some areas, hair may be deeper than on others, so settings have to be adjusted accordingly.

3

I am surprised that no one seems to be interested in overlapping or the application techniques.

Anyway, I’ve read the manual for this new Tria Home LHR Device: http://www.tria.co.uk/, and found out that the manufacturer recommends to use one of the application patterns above, namely number 7 , which seems to be the most power intensive of all.

I understand they chose an aggressive overlapping scheme since the device’s peak energy is limited and cannot compare to professional, more expensive systems. By the way, Tria’s specs are:

  • Laser class: Class 1
  • Laser type: Diode laser
  • Output wavelength: 800 nm
  • Output fluence: 6-24 J/cm2
  • Output pulse duration: 125-600 ms

A brief introductory information for those who are not familiar about this type specification and units:

  • It is classified as a Class 1 laser, because it is in the safest category for lasers and in no way can damage the eye. P.s. You definitely burn your retina if somehow laser directly reaches your eye, but since the device only operates when the head is firmly placed onto skin, it is very unlikely you hit your eye undeliberately.

  • It is called a diode laser; I guess it is because it uses physical medium that is also used in LEDs (Light Emitting Diodes). You can think of this as building material for the laser.

  • Wavelength determines how deep the laser penetrates into the skin. The higher, the deeper.

  • Fluence is a way of measure of how much energy is transferred in terms of photons. In this case, how many Joules onto 1 cm2 area during the pulse duration.

  • Pulse duration is the time that passes along a zap.

If you use higher output fluence, you have better chance of burning a hair follicle. If you use a higher pulse duration you have lesser chance of burning a hair follicle. In the light of this info, although this device’s output fluence is at par with other professional system’s (PS), its high pulse duration makes it less effective than the PSs. As a PS is able to transmit the same amount energy in a much shorter time, it is able increase the temperature much more , so it has better chance the burn the follicle.

Now, it should be much clear that why they recommend pattern 7.

Pattern 7 consists of 3 energy levels: 2P, 3P and 4P. This translates as, some areas are zapped twice, some other triple and some another quadruple. So, they actually endorse going over an area multiple times. This is important because it qualifies as an evidence if laser output is under control then we can safely double zap or more.

We know that, for some of us, sometimes laser energy does not turn out to be enough as some hairs do not shed. Now, my question is, for those areas which are stubborn, can’t we use an aggressive pattern such as number 7, so we could increase the possibility of shedding. Or, forgetting about the stubborn areas, for any area, for the sake of uniformity and to depress patchiness, can’t we decrease the output fluence and at the same time increase the pulse duration, and be able to use a similar pattern to number 7?

lagirl:
Generally, overlapping by 10% or so should be enough and won’t be destructive to the skin

Can you elaborate on this? I’ve seen this number on a scientific study too, however I am still not sure whether it is %10 by length, area or something else.

4

10% is used to make sure that all parts of an area are covered, since parts of the body are not all flat and the heads of the machines come in various forms. As far as I know, there is no benefit to going over the same area several times in terms of effectiveness. If the energy is not high enough and/or the beam is not penetrating deep enough, applying it more times over the same area is not going to change this fact and thus the effectiveness. Overlapping is done purely in order to make sure no spots are missed.

Btw, the problem with this device is that the spot size is very low, and that the highest joules can only be used in conjunction with high pulse, i.e. I do not believe you can use 24J max with 125ms, only 600ms. These factors is what makes this machine not likely to produce permanent damage to the follicle.

5

pulse duration (length of time current is delievered)is primarily used on skin type IV and above to protect the skin. Lasers do not destroy the hair follicle it targets the papilla and melanin. That is why lasers can not be marketed as permanent,rathe a long term reduction with maintenence required.

6

settings do not determine the wave length. The diode’s wavelength is 810 nanno’s whether the joules ar 20 or 60.

7

Zsazsa, I think I’m starting to get a good sense of what you do at your clinic and why you have opinions that differ so much from all the professionals in the industry who regularly participate in conferences on LHR.

Laser IS permanent and it DOES permanently destroy the follicle. And it CAN be marketed as “PERMANENT reduction”. So the reduction IS permanent, i.e. the follicles ARE disabled. What it cannot claim yet is “permanent removal”, and that’s because at a point some hair that remains gets too fine for laser to target.

I think I’m getting a pretty good idea of why your clients needs a lot of maintenance. You’ve stated in your other posts that you treat every 4 weeks and at very low settings, and felt that even 3 treatments was enough. And you feel adjusting the pulse is only necessary for type IV and above (when you shouldn’t be using a LightSheer on anyone type IV and above in the first place, because you have to drop down the joules too low to be effective in order not to burn them). It also amazes me that you gave up one of the best machines on the market, GentleLASE, for LightSheer diode, which leads me to believe you weren’t using it at high enough settings (if you were always following manufacturer’s chart, you likely were not). The way to get permanent results with LHR is by treating at high settings, from the start. As I suggested before, you may want to experiment with that. You may find your conclusions change and fall in line with the rest of the professionals who post on here and the consumers’ result posted here.

P.S. I’m also not sure if you’re actually reading any of the posts to which you reply or that you follow up on any questions asked of you. Your responses don’t really address the issue being discussed…i.e. No one mentioned above that settings determine the wavelength.

8

No, I said nothing about the depth of hair on the face or elsewhere. I like the diode over the GentlrLase primarily because it has a deeper wave length.Longer wave lengths mean deeper penetration of the joules. The joules and pulse width are determined by skin type and as always, there are some exceptions.

I overlap anywhere between 10-20%.If you read my other posts,i explained some reasons for patchiness–hair cycles. At the time of tx (on large surface areas) patchiness does happen even though all the hairs are treated. Not all the treated hairs are in anagen,therefore no visible shedding of those hairs. When the patient returns, there are obvious areas where laser effectively targeted and others where it did not. Any clearer?
Now I would like to properly introduce myself. I am a board certified dermatologist whose sub- specialty is hair. I have used a psuedo for the purpose of this site. I do not recommend drug therapy for any threads simply because it is irresponsible.

9

Lagirl, Above
This was my last post. You are twisting everything I have previously written.I never said I treat at the lowest joules.
Are you reading the full content of my posts? I am a board certified dermatologist,using a pseudo name for this site

Giving you the benefit of doubt,I think that you may not be reading my posts in sequential order. Some of the things you claim I said are false. I also am a professor at a large university hospital. I think I know what I am doing.
Laser is not a permanent reduction-it is a long term reduction.
Go back and revisit the FDA guidlines.
Everything I have said you have a negative reply,contradicting yourself in the process. Why do you challenge and dismiss what I say? Honestly!Make sure before you attack me read everything I have written.

10

zsazsa9:
Lasers do not destroy the hair follicle it targets the papilla and melanin. That is why lasers can not be marketed as permanent,rathe a long term reduction with maintenence required.

So, hair follicle can heal itself and return its previous strength? I mean after LHR, the pore is left with a fine hair, and this fine hair becomes a coarse one during the course of time?

11

lagirl:
10% is used to make sure that all parts of an area are covered, since parts of the body are not all flat and the heads of the machines come in various forms.

I assume %10 corresponds to pattern number 2

Am I right?

What types are other heads are used? Can you give examples?

12

The hair follicle does not “heal itself” if it has been properly treated.

What your most likely seeing long term is new hair growth. Not regrowth from hair that was previously destroyed.

The body stimulates new hair growth throughout life. Laser Hair Removal can only treat hairs that are currently growing. It cannot inhibit the body from activating new follicles to grow.

13

pdeco1;

Don’t want to sound harsh, but from what you wrote I infer you addressed a person who almost have no knowledge in hair. Do I look like such a person?

Ok, let me correct what I wrote. Let me say “the part of the skin responsible for generation of hair follicles” instead of “hair follicle”. By the way, “zsazsa9” claims follicle is NOT destroyed. I think she is trying to say; only the part that is feeding the follicle is destroyed.

14

So, hair follicle can heal itself and return its previous strength? I mean after LHR, the pore is left with a fine hair, and this fine hair becomes a coarse one during the course of time?

No,the follicle is not destroyed. The papilla which is the source of nourishment, to replicate a hair is disabled.Currently,electrolysis is the only form of permanent
hair removal.

15

No,the follicle is not destroyed. The papilla which is the source of nourishment, to replicate a hair is disabled.Currently,electrolysis is the only form of permanent
hair removal.

But, what does it mean to lose replicating ability for a hair? Practically, it sounds like, if replication is not possible we should not see any hair? Can you give us the details? Don’t worry about using medical jargon, as long as it is scientific it is useful for me.

16

Why you felt slighted I do not know. I try to respond clearly so that everyone can understand. It is difficult to have a discussion when those involved lack a clear understanding of English grammar.

I am not quite sure exactly what you are confused about, but the hair is not left with a fine hair follicle post LHR. The human body is covered in small vellus hairs. Some are very easy to see, some are very difficult to see. This may be why some people report laser induced hair growth on some parts of the body.

When you say “generation of hair follicles” do you mean currently active follicles and those still dormant that could grow in the future? If so, LHR can only treat hairs that are currently active. Unfortunately hair growth patterns change throughout life. For example, older men begin to grow hair from there ears. I have a current client that was virtually hair free throughout his 20s and 30s but became extremely hairy on his upper body in his 40s.

17

pdeco1, Yes,you understand me perfectly. Only part of the follicle is destroyed-which enables the hair to grow.

Vklepil, pdeco1 is correct saying that hair patterns change throughout one’s life.
I will post an answer to your previous question shortly.

18

When you say that a portion of the follicle remains intact. Which part of the follicle is destroyed and which part remains intact?

-I know many clients who have upwards of 95% removal. The hair they are left with are very fine and should be treated with electrolysis. This is not uncommon in the industry.

I am curious to understand what kind of results you are seeing after a full treatment regimen is completed.

19

I’m not twisting anything. Here’s a quote from your other post in response to my stating I had GentleLASE treatments at 16J at 18mm.

" would say you are very fortunate to be able to go 8-12 weeks before needing another laser treatment. We have used Gentlelase in the past and are now using LightSheer (diode). 16 joules and a pulse width of 18? -correct?"

Here’s the thread (I replied and asked you questions and you never responded). http://www.hairtell.com/forum/ubbthreads.php/topics/54869/Re_little_help_please.html#Post54869

How can you be an expert in LHR, supposedly used GentleLASE in the past and do not know that GentleLASE has a stable pulse at 3ms and that 18mm refers to the spot size? These are basics that even most consumers on this site know by now.

I’m not “fortunate”. If you read threads on this forum by people who’ve had successful treatments with good lasers at high settings as appropriate, they don’t have anything to treat at before 8 weeks. The only time they do is when most of the hair didn’t shed in the first place (due to low settings).

Also, I’m confused and it would help if you can clear this up. You have stated in several different threads just this week that you’re an electrologist, a laser hair removal technician, and a dermatologist. Which ones do you actually perform yourself?

20

LAGirl, this is my favorite zsazsa quote:

Maybe this is The Three Faces Of Janet?