Lasers have the unique ability to emit an intense beam of bright light of one color (wavelength). (Ordinary light is composed of many different colors and appears white.)
New, state-of-the-art lasers have revolutionized the treatment of a wide variety of skin disorders including spider veins, leg veins, birthmarks, hypertrophic scars, stretch marks, pigmented spots (freckles, age spots) and tattoos. They are also frequently recommended as part of a cosmetic rejuvenation program to create a more youthful appearance.
There are a variety of lasers, and each type produces a different color of light (wavelength) or distributes the light in a different pattern. These differences determine which tissue is affected by the laser and how it might be used to treat the skin. For instance, yellow-light lasers are particularly effective at treating red areas, such as birthmarks or visible blood vessels whereas red-light lasers are more effective at treating brown spots, such as age spots.
Some types of lasers for skin called ablative lasers are used to heat, cut, and remove superficial skin tissue such as pigmented lesions or blood vessels.
Non-ablative lasers work beneath the skin to reduce fine lines and wrinkles, leading to improved skin tone with minimal side effects and little recovery time.
Ablative lasers and their uses
Carbon dioxide (CO2) laser
CO2 lasers deliver powerful, focused light that can make “bloodless” incisions in the skin or vaporize unwanted tissue. They are often used for skin resurfacing, removing fine lines and wrinkles, smoothing acne scarred skin, and improving general skin contour. The CO2 laser beam can also be “defocused” and pulsed so that it can be used to remove warts, actinic keratoses, or superficial skin cancers.
Erbium (ER):YAG laser
Er:YAG lasers are often used to treat facial wrinkles, scars, and pigmentation that causes uneven skin tone.
Yellow light laser
Yellow light is more readily absorbed by hemoglobin in the body than other colors. This property makes yellow light lasers particularly effective for treating red areas of the skin, such as rosacea, port wine stains, red birthmarks, visible blood vessels, hemangiomas. These lasers are gentle enough to be used for treating children, such as those with birthmarks.
Green light laser
Green light lasers may be used to treat age spots (café-au-lait spots) and lentigines (freckles), as well small blood vessels.
Red light laser
The very short, intense light pulses emitted by red light lasers may be used for tattoo removal and brown-pigmented lesions, such as freckles or age spots. By altering the pulse duration, red light lasers may also be used to remove unwanted hair.
Ablative skin resurfacing
Ablative resurfacing involves the use of CO2, Erbium:YAG, and/or other lasers to remove the entire epidermis (superficial layer of skin) and portions of the dermis. Skin that may be damaged by age or other conditions is replaced by a layer of new youthful appearing skin. This treatment improves skin texture, removes fine and moderately deep wrinkles, and treats pigmented areas. While results can be impressive, there is discomfort, and the unpleasant healing period of 1-2 weeks during which time there is swelling, oozing and crusting of the skin.
Unlike traditional lasers, non-ablative lasers affect the tissue in the deep layers of skin. The epidermis (superficial layer of skin) is not visibly disrupted so there is little if any downtime.
Because of their non-wounding properties, non-ablative lasers are slowly becoming more commonly used for a variety of conditions, including acne scars, active acne, stretch marks, and problems with pigmentation.
Fractional resurfacing devices combine the benefits of non-ablative lasers and their ablative counterparts (such as CO2 lasers). The procedure works by creating multiple zones of skin injury with intact skin between the treated zones. This stimulates collagen renewal, which leaves the skin smoother and softer as it heals.
Side Effects and Safety
There are rarely any permanent problems with laser therapy. Occasionally some lightening of the skin occurs. Normal skin color returns within three months after treatment of vascular lesions. Although rare, a slight depression may develop, which usually resolves in a few months. Scarring occurs in less than one-tenth of one percent of all cases. Because lasers produce an intense bright beam of light, everyone in the treatment room is required to wear protective eyewear.