Introduction – Laser Hair Removal
There are many methods of intense pulsed light therapies available for hair removal. Laser hair-removal systems are categorized as stated below based on the type of laser or light source each uses:
- red-light systems
- infrared-light systems (alexandrite, diode, and Nd:YAG)- ‘Nd’ stands for Neodymium, and ‘YAG’ stands for Yttrium Aluminium Garnet
- intense pulsed-light sources
The difficulty in permanently disrupting hair growth using laser irradiation can be due to two reasons-
- the exceptional ability for follicular self-repair and renewal
- the varying anatomical locations, sizes, depths, and melanin concentrations of hair
Therefore, current laser hair-removal systems are devised to irradiate as much of the follicle as possible. Thus, only lasers emitting energy with wavelengths ranging between the range of 630 to 1100 nm can potentially irradiate the entire length of anagen hair follicles, which normally extend 2 to 5 mm into the dermis.
The Nd: YAG laser (1064-nm) can penetrate from 5 to 7 mm into the dermis, depths of which are more than adequate to reach the base of the bulb in most anatomical areas, and would therefore be expected to make sufficient follicular injury with less epidermal damage in patients with pigmented skin.
The Nd: YAG laser has been of interest in the field of laser-assisted hair removal because of its early introduction and its known high safety profile. This latter attribute is particularly important when people having darker skin tones seek treatment.
The longer-pulse Nd: YAG system of millisecond has been shown to be more efficient in safely removing hair than has the Q-switched Nd:YAG system of nanosecond, given its closer approximation to the target hair follicle’s thermal relaxation time.
The use of lasers with longer pulse durations (≤200 milliseconds) allow secure application of higher fluences to patients with darker skin tones, effectively heating the inner and outer root sheaths and the germinative zone without disrupting epidermal melanosomes.
Key points – Laser Hair Removal
- ‘Nd’ stands for Neodymium, and ‘YAG’ stands for Yttrium Aluminum Garnet.
- Nd YAG Laser is of 1065nm infrared wavelength.
- It is excellent for people with darker skin as there is much less melanin absorbtion than with shorter visible light wavelengths.
- Recommended for darker skin types
- The advantage with Nd YAG is that as the wavelength is longer, there is much deeper penetration into the dermis 4-5mm with much less risk of changes in pigmentation. It also has a rapid recurrence rate and can be used on larger areas of skin like the legs and the back.
- Pre Treatment- Shave the treatment site to reduce the smell of burning hair and stopping long hairs from getting in the way of the skin/ follicles being treated.
- Treatment- The area to be treated is covered in a carbon which acts as a chromophore as it is a better target than melanin at 1065nm wavelength. The carbon penetrates the hair follicles which then absorb the wavelength from the Nd YAG laser.
- Some may feel more pain with the faster rates of repetition.
- Hair is reduced or eliminated for about six months with the Nd:YAG laser. For birthmarks, discolorations and veins, the laser can lighten or remove existing marks, but it won’t prevent newer ones from growing.
- Links of interest:
American Society of Plastic Surgeons website
British Association of Aesthetic Plastic Surgeons website
This article is not medical advice nor a substitute to professional health advice. Always consult a doctor.