The carbon dioxide laser became popular in 1994 as a high-tech method of wrinkle reduction. Computers shape the high-intensity light energy to patterns of squares, lines, or circles. Like an artist paints with different brushes, the surgeon uses these varying shapes to vaporize different zones of the face. The initial results were dramatic and the laser soared in popularity, but as with so many new technologies, problems and complications arose.Pigment changes and scarring are common with this laser, and some of these changes do not appear for months or years. The laser was expected to cause fewer pigment problems than deep chemical peeling because the pigment-producing cells (melanocytes) were thought to be preserved. Yet over half of patients have lightened skin after the laser.Because of scarring and pigment problems, a ‘‘lighter’’ laser, the Erbium, was introduced in 1999. It causes less heat damage than the carbon dioxide laser but is less effective in treating wrinkles. There seems to be a ‘‘no pain, no gain’’ principle here. Heat injury apparently contributes to some of the wrinkle reduction. The Erbium laser does remove the weathered upper layers of skin, allowing new skin to be formed and causing some shrinkage of the skin during healing.Preparation is identical to that for a deep chemical peel. Laser peels are performed under local anesthesia with intravenous sedation or with general anesthesia. The eyes are protected with steel contact lenses.The pulsed carbon dioxide and the Erbium laser both sequentially remove layers of skin. With the CO2 laser, the skin is blasted two or three times. The first pass removes the epidermis. Nurses in the operating room are very impressed with the second pass, as the skin visibly shrinks before their eyes. The third pass is usually reserved for the deeper wrinkles. Recovery and aftercare are similar to that for the deep chemical peel.Problems with Laser PeelsMany complications can occur with lasers. The laser can set hair and surgical drapes on fire, making for an unpleasant day. It can ignite the oxygen being delivered to the patient, causing a potentially deadly explosion.In the early days of the laser, corneal injuries and eyeball perforations were frequent. Even today, scarring and pigment changes are common. Brown pigment streaking and lines demarcating where the laser stopped can occur. This hyperpigmentation can be extremely troublesome and may require skin creams such as tretinoin and hydroquinone, peels, microdermabrasion, and even repeat lasering. It may even be permanent. The skin can scar over the years, stiffening and lightening. The cells that make pigment are destroyed by the heat of the laser, making it dangerous to be in the sun without complete sunblock.Infections from laser peels can cause scarring. If a herpes infection occurs, it can create chicken pox–type scars. Antiviral drugs such as Zovirax and Valtrex can prevent this complication and should be used in all patients undergoing a laser peel.About 10 percent of patients do not achieve much wrinkle reduction. A second laser a few months later usually further decreases wrinkles.Thick red scars or even keloids are possible after lasering. Accutane or steroid use prior to lasering will delay healing for up to a year, which can cause intense scarring.Since lasering really does work and really does shrink the skin, it can cause the eyelids to shrink to the point that they do not close. An experienced surgeon will know how deeply to laser and whether the lids require a tightening procedure such as a canthopexy to prevent this complication.The laser is safe only on the face, since the skin of the neck and the rest of the body heals differently. Scars are more common in other areas.The laser will permanently damage teeth. They are protected with a gauze pad or mouthguard during the procedures.After the skin has regrown, it is bright red for months, even up to a year. A skin reaction called milia, or ‘‘whiteheads,’’ often occurs a few months after the peel; it is helped by tretinoin and exfoliants.The deep laser peel is declining in popularity, mostly because of the high chance of skin lightening and the uncomfortable, lengthy recovery. In 1996, there were 46,000 deep laser peels performed in the United States. After a peak in popularity around the year 2000, by 2005 there were 58,000 deep lasers performed. Because it so effectively lessens wrinkles, the laser peel is still selectively used despite its problems. On the other hand, 418,000 so-called nonablative laser peels were performed the same year. In these, the upper layers of skin are not removed.To take advantage of the aggressive skin smoothing effects of the carbon dioxide laser but to limit healing problems, lower power levels are now being used. The skin is left intact and acts as a dressing. The ‘‘light CO2 laser,’’ as it is called, does decrease wrinkles, but not as aggressively as the more powerful version. It can be performed with only EMLA cream anesthesia and patients recover within a week without oozing. It doesn’t appear to cause skin lightening.