Paradoxical Laser Hair Stimulation

I will ask! Shapiro has a Dermatology department at University of British Columbia to run, and Rivers is a working practitioner with a pretty successful laser practice :wink: So I don’t know how available they are.

You forgot to mention Cynosure Elite MPX that has an 18mm spot size. That model has been out for a few years now.

Yes yes… sorry… Also forgot the Elite+ which is not a multiplex system, but also has an 18mm spot size.

So I spoke with Dr. Rivers of the Vancouver Dermatology & Laser Skin Care Clinic, one of the authors of a “study” that was used to start this thread, and has been repeatedly cited throughout.

A few things he pointed out to me- it doesn’t seem anybody who is commenting on the paper has actually read it. He suggested I purchase the paper, and I have. I will read it and follow up with my findings tomorrow.

He also pointed out that this was not a study, and should not be cited as scientific- the doctors had received complaints from patients, and decided to retroactively review the procedures that had been performed on them. He called it a “chart review.” The doctors did not take part in the treatments, and the documentation was done by the practitioners themselves as part of their regular work. This leaves great room for error, for example, in logging of treatment parameters, though he said much of that is available in the paper.

I asked the following questions:

ME: In my experience, and with my knowledge of the physics of lasers, and the mechanisms at work during laser hair removal, I find the term “paradoxical” to imply an unknown- is laser stimulation of hair “paradoxical,” or is it part of the normal function of laser on hair?

DR: We used the term paradoxical because the device itself is supposed to remove hair, not stimulate new hair growth.

ME: Do you think laser is stimulating new hair growth through an unknown mechanism of laser?

DR: Laser seems to stimulate new hair growth in patients with darker skin, and at lower fluences. The information from this article is being used to develop LLLT (low level light therapy) devices that stimulate hair growth.

ME: That’s a little confusing. Are you saying LLLT uses an unknown mechanism to stimulate hair growth?

DR: No. I’m saying laser hair removal lasers are supposed to remove hair, not stimulate it.

ME: It is my understanding that there are two desired mechanisms in laser hair removal- lethal injury to the follicle in anagen hair, and sublethal damage to the follicle in telogen hair. Can any of these mechanisms be the cause of the new hair growth?

DR: The laser seems to stimulate the epidermis around the hairs.

ME: Hyperemia is a natural occurrence in all laser treatments though, right?

DR: Subdermal heating will almost always cause increased blood flow to the area.

ME: Ok. So is it safe to say that if subdermal heating is normal, there could be some other mechanism of laser causing the new hair growth… like sublethal damage to dormant telogen hair, or shock to vellus hair?

DR: I believe that is not only possible, but probable.

ME: Ok. So if sublethal injury to the follicle is an expected mechanism of laser, and all other options are speculation…

DR: I would say sublethal injury is the primary cause of stimulation.

ME: Should we call it paradoxical? Is the laser not doing what it’s supposed to do?

DR: It’s paradoxical because the machine is supposed to remove hair.

ME: Fair enough. Do you believe this new hair growth is treatable?

DR: Yes. I really think it’s best of you purchase the paper. There are many questions you have asked, and will ask that are answered in the paper. It’s not a study- it’s a review of our past treatments, and we had this review published. Also, this was almost a decade ago. I can’t remember all the details, but the paper answers more questions than a summary can tell you.

ME: Dr. I appreciate your time, and patience with me.

I told him about the site, and about the request for the authors to participate on the site. He sounded interested at first, but expressed he doesn’t have time. Maybe one of these days he’ll show up and answer questions for himself :wink:

I have read the paper in full and the paragraphs I posted in the L.I.T thread were copied/pasted from it. I have offered to email it to people in the past.
http://www.hairtell.com/forum/ubbthreads.php/topics/106880/stoppit_tidyup.html#Post106880
The authors make some attempt to explain what may be going on. It’s the only useful part if you ask me. Most of these papers suggest further Laser to resolve the stimulated hair. Some posters of this forum have tried but it was not successful.

Offline, I’ve been following the Laser treatments of many people and the few that I have experienced this and continued with Laser to resolve, were unsuccessful in doing so. Generally they purchased package treatments and had great results on the parts of the body we know respond very well to Laser. Maybe there are a great many shortcomings with the treatments they were having in regards to the stimulated areas but the fact remains that is has happened and has not yet been resolved. I know first hand how difficult it is to find a good Laser clinic where you leave the consultation having had a test patch where the settings were good enough to start with. Unfortunately, this is the reality that consumers are facing.

The conclusion I draw after reading the answers of Dr. is that the paradoxical effect is a risk that the customer who chooses laser treatments should consider.

So after reading the paper, I have to say I’m very disappointed with the wording of their findings. Knowing these were dermatologists writing the findings makes me think they really didn’t take this paper seriously, and weren’t really interested in resolving their patient’s issues. Considering these were patients that had undergone 13 treatments each, and they waiting at least a year after the last patient complaint to do anything about it is just ridiculous. Here are my own observations after reading the treatment parameters, history, and viewing pictures:

The laser used was the very first laser approved for permanent hair reduction. I know this laser very well, as I am a service partner and distributor for the manufacturer of the laser, Light Age, Inc. Of course I’m talking about the Sharplan Epitouch 5100- the grandfather of nearly every hair removal laser since. My own personal knowledge of suggested treatment parameters are largely dictated by the work of Dr. Heller, the patent holder for this laser, and the CEO of Light Age, Inc. This laser was first introduced into the market in 1993.

Case 1: June 1999-June 2003
39yo F, Type IV, Mediterranean
Facial hair- thin, light to dark brown, 1.5 inches average length (from photos, not stated in the study)
First treatment: 7mm, 23J/cm2/30ms (time between pulses not noted)
Final treatment: 7mm, 37J/cm2 (pulse width/time between pulses not noted)
The doctors noted that tests were done for hyperandrogenism. They didn’t do tests for hirsutism, and didn’t take into account any other factors which may have caused hair growth. First of all, upon examining the pictures, I don’t agree there is “longer, thicker, darker” hair growth. What I did note is that there was barely any hair visible in the original picture- she may have shaved in preparation for her first treatment- this is not noted. However, the “new hair growth” looks natural, and treatable.

I can’t say these are vellus hairs that have gone terminal- they appear to be miniaturized terminal hairs both before, and after. While this is the only case I find compelling in the least bit, I do have some issues with the treatment.

First of all, facial hair lies at anywhere between 10 degrees, and 45 degrees. This, in and of itself, makes treatment difficult. A very experienced technician or dermatologist should make the recommendation as to whether laser hair removal is an option to begin with.

Second, the combination of spot size, energy, and pulse width are unheard of to me for skin type IV with an Alexandrite laser. Dr. Rivers, and the paper itself, refer to these settings as “low fluence.” I disagree. This is unusually high for a skin type IV with 755nm… but I’m not a clinical expert.

With that said, skin type IV should be treated with a 1064nm laser, and that treatment could have been delivered far more aggressively. The max setting on the Epitouch is 40J, but the pulse width is not long enough for skin type IV. I am skin type V, and the minimum setting on a Yag laser for efficient hair removal on my body is 25/25, and the standard is 35/35 with a minimum 10mm spot size. Spot size does affect depth of treatment, and pulse width affects melanin absorbtion of the laser. Because 755nm has less absorbtion into melanin in the hair, and more absorbtion into melanin in the skin than 1064nm, much longer pulse widths should be used when treating darker skin types to get the same effect. So if 25/25 is effective in Yag at 10mm, 23/30 at 7mm with 755nm is not at all enough time for melaning abosorbtion (though the energy is a little high for skin type IV).

Of course, I could be all wrong :-/

Case 2 and 3 pissed me off, and I won’t even explain much other than the following:

Case #2- The pre-treatment pictures show some back hair with almost no acne. The post-treatment pictures show more back hair (not significantly more, not thicker, not darker, not longer) and significant acne. This is obviously a case of androgenic hypertrichosis. The paper does not note the new acne, and ignores this was a 30 year old male. 13 treatments over a period of 2 years on the back is ridiculously excessive. Telogen in the back is 9 months. 6 treatments should take a minimum of 18 months.

Case #3- This was a 21 year old male who experienced androgenic alopecia in other areas after starting treatment on his face. First of all, he’s 21. Second, the guy clearly has significant acne in the post-treatment picture, and NONE in the pre-treatment picture. Now get this- he was taking 1mg of Finasteride per day for 2 months prior to his complaint of… NEW ANDROGENIC HAIR GROWTH. He was taking Finasteride to treat androgenic alopecia!!! While this is noted in the paper, it is dismissed as the cause because Finasteride has been used to treat androgenic hypertrichosis in women. WHAT??? Finasteride is a growth stimulator- like Minoxidil.

In any case, I don’t buy the last two cases. This is ridiculous. The first case is questionable, and barely compelling. The fact that these people ignored clear signs of androgenic stimulation is horrible considering the paper is cited 68 times in other articles and papers.

I am more convinced after reading this “study” that “paradoxical” hair growth is a normal function of lasers being used by amateurs.

I am a 31 year old female of Irish decent. I decided to undergo laser hair removal when I was 25 years old- I had all my treatments with Laser Clinics Australia.

I had a few sessions on my face and arms for pigment removal (I think the Candela GentleLASE laser was used). A few months after the treatments course hair appeared all in all areas that had been treated (including my forehead).

I had about 5 treatments with the YAG and 20 with Candela GentleLASE lasers. This treatment made the hair even worse but as I only had the YAG periodically I can’t say which was the main source of stimulation. For these sessions which aimed to reduce the paradoxical growth the settings were high.

I had about 10 sessions of Candela GentleLASE on my full legs: the treatment has been partly effective for my lower legs but from above my knew to my bikini line I have thick dark hair that I never had.

I have spend thousands of dollars on my face and arms with electrolysis which has been effective and still ongoing (with probably years to go)but I can’t afford to do the same for my legs and given the number of hairs located in this area electrolysis would not see practical of such a large area.

I know that my legs were treated with a range of settings- starting from low to very high for about 5 sessions. As I had regular treatments I can’t speculate as to when the prominent hair growth commenced.

I don’t want to just bleach, shave, or wax.

I would be extremely if anyone has any ideas on what kind of machine or settings may be effective in removing or reducing my course dark paradoxical hair growth.

A dermatologist who knows what they are doing should not have this issue. I has to with sub-optimal fluences being used.

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