Both cosmetic and noncosmetic laser surgery do not usually require anesthesia (medication used to eliminate pain). However, some patients may require a topical (applied directly to the skin) or intralesional (applied directly into the lesion) anesthetic for extensive procedures such as the removal of large pigmented lesions, extensive tattoos or the treatment of sensitive areas (e.g., fingers). In addition, laser surgery may be difficult for children and require the use of anesthesia in some form (e.g., local anesthetic).   

Before the procedure, the operation site may be cooled with cooling gel or active cooling systems that are integrated into the laser apparatus. This helps reduce pain and the risk of adverse effects (e.g., scarring). It also allows the laser to be used at higher settings for increased effectiveness. Neighboring areas of the skin may also be covered to prevent unnecessary tissue damage. Protective eyewear is also typically worn by everyone in the room (including the patient) to prevent any potential eye damage.

During laser resurfacing for wrinkles with a CO2 laser, the laser is first passed over the affected area to remove the top layer of skin with as little overlap as possible. This is followed by a gentle but thorough wiping of the dried out (desiccated) debris with saline-soaked sponges. Finally, the borders of the affected area are blended with the surrounding tissue by decreasing the energy and density of laser pulses.

The technique of laser resurfacing varies somewhat if an Er:YAG laser is used. Up to four passes may be required to remove the top layer of skin and as many as eight passes may be needed to complete the procedure. The treated area is typically covered with pulses that slightly overlap.

Acne scars are removed with a different approach than typical skin resurfacing because deeper penetration of the skin is necessary to achieve an acceptable result. The edges of the scar may be treated before the rest of the face because facial swelling during the procedure may obscure the acne scars.

Laser hair removal is usually performed by using heat from the laser to destroy the hair follicle. Most lasers do this by targeting melanin, the substance in the skin that absorb light and produces color.

Laser use for tattoo removal is largely dependent upon the type of tattoo and its pigment (color). Tattoos consisting of more than one color may require the use of more than one laser and more than one treatment session for complete removal. Professional tattoos tend to have a greater variety of inks and colors and therefore may be more resistant to laser treatment. In contrast, amateur, single-colored or older tattoos typically respond better to lasers and require fewer treatments.

Vascular lesions (e.g., rosacea) are most often removed with pulsed dye laser (PDL) pulses emitted through a hand piece held by the operating physician. The pulses of the laser are placed closely with a slight overlap to avoid missing areas between spots. Disappearance of the lesions and/or a slight redness often indicates the endpoint for treatment. 

The techniques and characteristics of laser surgery for removing pigmented lesions (e.g., moles) may vary depending on the type of laser being used, the type of lesion being treated and the color of the patient’s skin. Generally speaking, stronger lasers are used for lesions that extend deep into the skin, whereas more superficial growths or markings are removed with lasers of lower intensity. Patients with darker skin are typically treated with lower energy settings than patients with lighter skin. The number of treatments required may also vary depending on the type and anatomic location of the lesion being treated. Some lesions may require one treatment but others require multiple procedures.