I had patch test with Lightsheer Diode Laser at 3 different laser clinics. Each clinic used the almost same settings. At the first two clinics, they shaved the area and applied gel before treatment. After treatment, my skin got red and some bumps appeared, but I didn't burn. But when I had patch test at the third clinic, electrologist didn't shave and apply any gel before treatment. When she treated the area, I burned and got blister on my skin.
When the similar setting was used with same laser, why did my skin react differently? At the first 2 clinics (which use Lighsheer frequently on clients), I was told that my skin is good for Lightsheer but at third clinic (which uses more GentleYAG on clients), I was told that Lightsheer is not good for my skin. Why is this?
Light Sheer is good for types I – III skin but darker skin, IV – VI may absorb too much energy in the darker skin and the heat gets trapped there rather than being absorbed deeper in the hair follicles. This epidermal heating could result in more of a reaction.
Furthermore, if hair is visible, then it should be shaved, otherwise it is laying on top of the epidermis and serving as a target for the laser energy, bringing more heat to the epidermis. You want the heat to be brought down to the hair follicle. The gel is not mandatory, but shaving most certainly should be done. It’s best if you can shave prior to your appointment next time.
The Gentle Yag is a longer wavelength so it doesn’t get trapped as much on the more superficial epidermal pigment. It penetrates deeper to the hair follicle but may be slightly less effective than the Lightsheer diode laser, but the Gentle Yag may be safer on dark skin.
LightSheer laser or LightSheer Duet laser is generally very effective and safe for all skin types, but like most laser hair removal systems, it is most effective when there is a great contrast between hair colour and skin (e.g. white skin, black hair). The hair should be shaved by you or the clinic the night before or morning of; I would avoid the 3rd clinic. Dr. Benjamin Barankin, Toronto Dermatology Centre.
LightSheer DUET laser should be used on dark hair in a fair-skinned person. It sounds as though the patch tests at the first 2 clinics gave appropriate results. The areas to be treated must be shaved and gel must be used or else you will burn, as you found out at the third clinic. Avoid treatment at the third clinic. The first and second clinics seemed to use appropriate settings.
Pigment is the target for hair reduction lasers. Light from the laser is attracted to pigment and when it finds it heat is released. Pigment in surface hair and in the top layer of skin will create heat (and can burn you) but does not affect the results of the hair reduction. To keep the skin cool while delivering the most effective treatment it is advised to remove surface hair by shaving prior to treatment. Some lasers require gel for cooling as well, some have chilled treatment tips. It may be that best practices were observed at the first 2 clinics and the result was a better patient experience.
You must be as well-shaven as possible prior to any laser hair treatment to achieve maximal clinical result as the hair shafts compete with energy of the laser (and we want most of the energy to be absorbed by hair follicles) and these residual hair shafts may be carbonized and can subsequently amplify the energy of the laser leading to blistering and scabbing. Protocol for Lightsheer needs to be more conservative for darker skin types, e.g. lower energy with greater pulse duration.
To determine if the Lightsheer is right for your skin type, we would need to evaluate your skin up close, understand your ethnic history and determine if you've had any sun exposure recently.
Just because the first two clinics test spots did not result in a blister (like the third one) does not mean you are appropriate for the Lightsheer. The fact that you had redness and follicular edema (the small bumps) is a good sign, but it does not necessarily mean that the first two practitioners were using high enough settings to result in permanent hair reduction. On the other hand, the fact that the third practitioner did not shave you or use gel is a problem. This could be the source of the blister.
It's a difficult question for this forum as we have no pictures, no medical/ethnic history and no settings. Since you did not have any adverse reactions at the first two facilities, we would suggest trying one of those. If you do not achieve 20% - 30% after 2 treatments then they are not using high enough settings and you may be a candidate for the GentleYag laser.
Even though the Lightsheer is good for all skin types, people with light skin and dark hair will get faster results. Shaving the hair first is very important and will prevent burning the skin during the treatment. Gel is used only to help the laser slide easily and it also has a cooling effect on the skin. With the Lightsheer you will see immediate hair reduction no matter what skin type you are, it just takes longer for darker skin, but the end results are the same.
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