ND: YAG Laser
Neodymium-doped Yttrium Aluminum Garnet (Nd: YAG) laser is a solid state laser in which Nd: YAG is used as a laser medium.
These lasers have many different applications in the medical and scientific field for processes such as Lasik surgery and laser spectroscopy.
Nd: YAG laser is a four-level laser system, which means that the four energy levels are involved in laser action. These lasers operate in both pulsed and continuous mode.
Nd: YAG laser generates laser light commonly in the near-infrared region of the spectrum at 1064 nanometers (nm). It also emits laser light at several different wavelengths including 1440 nm, 1320 nm, 1120 nm, and 940 nm.
What is neodynium YAG laser used for?
The following skin disorders can be treated with Nd:YAG laser beams.
- Spider and thread veins in the face (cheek, temporal region, nasal dorsum, forehead) and legs.
- Vascular birthmark (capillary vascular malformation)
- Varicose veins
- Facial veins (telangiectasia)
- Haemangioma (vascular tumour)
The laser light pulses target red pigment (haemoglobin). Typical settings employed for the treatment of facial veins include a 50 milliseconds pulse duration, and fluence (ie output energy) of 150¬250 J/cm2 (measured in Joules per centimetre squared).
- Nd:YAG laser can be used to remove brown age spots (solar lentigines), freckles, naevus of Ota, naevus of Ito, mongolian spots, Hori naevus and café-au-lait-macules.
Light pulses target melanin at variable depth on or in the skin.
- Nd:YAG laser may be used for hair removal in any location including underarms, bikini line, face, neck, back, chest and legs.
- Nd:YAG laser is generally ineffective for light-coloured (blonde/grey) hair, but effective for treating dark (brown/black) hair in patients of Fitzpatrick types I to III, and perhaps light-coloured type IV skin.
- Extreme caution is recommended in tanned or darker-skinned patients, as the laser can also destroy melanin, resulting in white patches of skin (leukoderma).
The longer-pulse (millisecond) 1064-nm Nd:YAG laser system has been shown to be more effective in safely removing hair than has the Q-switched (nanosecond) Nd:YAG system.
Light pulses target the hair follicle, which causes the hair to fall out and minimises further growth. Typical settings employed include pulse durations of 2 to 20 milliseconds and fluences of 10¬40 J/cm2.
- Blue, grey and black tattoos can be removed with a Q-switched Nd:YAG laser (1064 nm wavelength).
- The colour of the tattoo and the depth of the pigment influence the duration and the outcome of the laser treatment.
- Laser treatment involves the selective destruction of ink molecules that are then absorbed by macrophages and eliminated.
Typical settings are pulse duration: 10 nanoseconds, output energy: 300¬500Mj.
- Onychomycosis is a common nail disorder caused by fungal pathogens.
- Several laser devices have been granted FDA marketing approval for the treatment of onychomycosis.
- The first two lasers that were sanctioned by the FDA for the treatment of onychomycosis (PinPointe™ FootLaser™ [Cynosure, Massachusetts, USA ] and Cutera GenesisPlus™ [Cutera, California, USA]) are both flashlamp pumped short-pulse Nd:YAG 1064 nm lasers.
- These lasers emit 100–3000 microsecond pulses with an energy fluence of 25.5 J/cm2 for a 1 mm spot size.
Other uses of neodynium YAG laser
Nd:YAG lasers have also be used to improve wrinkles in photo-aged skin.
What does the laser procedure involve?
It is important that the correct diagnosis has been made by the clinician prior to treatment, particularly when pigmented lesions are targeted, to avoid mistreatment of skin cancer such as melanoma.
- The patient must wear eye protection (an opaque covering or goggles) throughout the treatment session.
- Treatment consists of placing a hand piece against the surface of the skin and activating the laser. Many patients describe each pulse feeling like the snapping of a rubber band against the skin.
- Topical anaesthetic may be applied to the area but is not usually necessary.
- Skin surface cooling is applied during all hair removal procedures. Some lasers have built-in cooling devices.
- Immediately following treatment, an ice pack may be applied to soothe the treated area.
- Care should be taken in the first few days following treatment to avoid scrubbing the area, and/or use of abrasive skin cleansers.
- A bandage or patch may help to prevent abrasion of the treated area.
- During the course of treatment patients should protect the area from sun exposure to reduce the risk of postinflammatory pigmentation.