What is a laser?
The acronym LASER stands for light amplification by stimulated emission of radiation. A laser works by emitting a wavelength of high energy light, which when focused on a certain skin condition creates heat and destroys diseased cells. Wavelength is measured in nanometres (nm).
Various kinds of lasers are available; they are differentiated by the medium that produces the laser beam. Each of the different types of lasers has a specific range of utility, depending on its wavelength and penetration.
What is erbium YAG laser?
- Erbium YAG (Er:YAG) lasers are solid-state lasers whose lasing medium is erbium-doped yttrium aluminium garnet (Er:Y3Al5O12).
- The triply ionised erbium dopant (a substance added in minute amounts to another pure substance to alter its conductivity) typically replaces a small fraction of the yttrium ions in the host crystal structure, since the two ions are of similar size.
- The erbium provides the laser activity in the crystal.
- Er:YAG lasers typically emit light with a wavelength of 2940 nm, which is infrared light.
- Unlike Nd:YAG laser, the output of an Er:YAG laser is strongly absorbed by water.
- This fact limits the use of Er:YAG laser in surgery, and in many other laser applications, to where water is present (healthy skin has a high water content).
How does erbium YAG laser work?
Lasers work by emitting a wavelength of high energy light, which when focused on a certain skin condition will create heat and destroy diseased cells.
What is erbium YAG laser used for?
The following skin disorders can be treated with Er:YAG laser beams.
- Atrophic acne scars
- Herpes simplex scars, smallpox scars
- Sun damaged skin
- Mild to moderate facial wrinkles
- Uneven pigment (brown age spots, freckles, melasma)
- Seborrhoeic keratosis and other benign skin growth
- Some superficial non-melanoma skin cancers
- Some vascular birthmarks (capillary vascular malformations)
Commonly used erbium YAG laser settings
Typical settings employed for birthmarks, age spots and superficial skin ablation are wavelength 2940 nm, short pulse, laser output 2.5–5 J/cm2, and pulse duration 250 microseconds.
For relatively deep-seated scars, long pulse settings are preferable, at wavelength 2940 nm, laser output 3 J/cm2, and pulse duration 1000 microseconds.
Patient selection and contraindications
Contraindications
Erbium YAG laser treatment may be unsuitable in the following circumstances:
- Unrealistic patient expectations
- Tendency toward keloid or hypertrophic scar formation
- Reduced numbers of adnexal skin structures (hair follicles, sweat glands), such as in scleroderma, and burn scars
- History of prior ionising radiation to the skin
Precautions
All patients should be carefully examined before treatment.
- The eyes must be examined for scleral show (whites of eyes visible below the iris), lid lag (slow movement of eyelids), and ectropion (drooping of the lower eyelid) in patients desiring periorbital laser treatment.
- The presence of cutaneous disorders including seborrhoeic keratoses, solar lentigines, actinic keratoses, and skin cancers should be noted.
- Skin cancers must be treated adequately by other methods before any resurfacing procedure is performed.
- Laser skin resurfacing can lead to reactivation of latent herpes simplex virus infection or predispose the patient to a primary herpes infection before the skin surface has healed.
- Little data exist to support the use of prophylactic antibiotics because of the relatively low incidence of bacterial infections reported.
Are there any side effects from erbium YAG laser resurfacing?
Side effects from Er:YAG laser treatment are usually minor and may include:
Mild side effects
- Milia
- Acne exacerbation
- Contact dermatitis
Moderate side effects
- Localised herpes simplex, impetigo and candida infection
- Prolonged redness
- Postinflammatory hyperpigmentation
- Delayed hypopigmentation (white patches)
Severe side effects
- Fibrosis (normal scarring)
- Hypertrophic scarring
- Disseminated herpes or staphylococcal infection
- Development of ectropion (outward rolling of the eyelid margin).
Benefits of erbium YAG laser treatment
For selected skin conditions, Er:YAG laser treatment offers:
- High-precision, tissue-selective treatment
- Intuitive, easy-to-use parameter selection
- Minimal residual thermal injury to the underlying tissue leading to less chance of persistent post-treatment redness and changes in pigmentation
- Low cost of consumables
- Less invasive than dermabrasion and chemical peeling
- Short downtime.