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