NEW ORLEANS – Identifying the right treatment for each type of acne scar and using a combination of modalities can yield the best results, according to Dr. Jennifer Chwalek.
Multiple safe, effective, and cost-effective options are available for the treatment of acne scarring, Dr. Chwalek said at the annual meeting of the American Academy of Cosmetic Surgery.
Dr. Jennifer Chwalek
“These techniques are often underutilized, but they’re very easy to put into practice,” Dr. Chwalek said. “With laser resurfacing techniques, they can add to patient improvement and better outcomes.”
Acne is the most common skin disorder in the United States, affecting an estimated 40-50 million people, and by their mid-teens, more than 40% of Americans have had acne accompanied by some scarring, said Dr. Chwalek. The appearance of these scars often worsens and becomes more prominent with aging, she added.
Acne scars are classified by their morphology as ice-pick scars, boxcar scars, and rolling scars. Different categories of scars require different approaches to minimize their appearance and maximize patient satisfaction, said Dr. Chwalek of Mount Sinai Medical Center in New York. Ice pick scars are characterized by small, deep holes in the skin with a wide opening and a narrow base. Boxcar scars present as square or U-shaped depressions in the skin. Scar morphology is a key driver of treatment options; ice pick and boxcar scars can be treated surgically through punch excisions, grafts, and elevation, and through the chemical reconstruction of skin scars technique, Dr. Chwalek said. Skin resurfacing procedures such as chemical peels, dermabrasion, and ablative and nonablative laser resurfacing can also be used to address acne scars. “However, lasers cannot always penetrate deep enough to address deep ice pick and boxcar scars; as a result, outcomes from laser treatments really fall short of our expectations,” she said.
With a punch excision, the acne scar is surgically removed through a punch matching the size of the scar (ideally 1.5-3.5 mm), and the remaining wound is sealed. Punch excision is ideal for deep ice pick scars and narrow, deep boxcar scars (<3 mm), said Dr. Chwalek. “As scars become larger, it is often better to treat with elliptical excision – otherwise you risk contour deformities,” she advised.
The punch elevation method is best for shallow and deep boxcar scars, Dr. Chwalek said. Scars treated with this method should have sharp edges, so the center of the scar can be elevated to the level of the surrounding tissue and reattached by a suture, Steri-Strips thin adhesive strips, or 2-octyl cyanoacrylate glue. Punch elevation brings scars up to the surface level of the skin, making them appear less noticeable, she said.
Punch grafting is an option to treat very deep, large, and more atrophic scars, Dr. Chwalek said. Skin that is not cosmetically sensitive is ideal for this method, and pre- or postauricular skin is typically utilized. However, there is a risk of textural or color mismatch when using this method, Dr. Chwalek noted
For deep acne scars, punch excision, elevation, and grafting are particularly effective when combined with laser resurfacing. “Combining surgical approaches with laser can really result in improvement for the patients,” said Dr. Chwalek.
Histologically, acne scars show a reduction in collagen and elastin. “Chemical reconstruction of skin scars [CROSS] is a technique of applying high concentrations of trichloroacetic acid [TCA] to atrophic ice pick scars to induce inflammation and collagen production,” Dr. Chwalek explained. The CROSS method causes coagulative epidermal necrosis and collagen necrosis in the papillary and upper reticular dermis, resulting in scar remodeling over time.
With the CROSS method, a 50%-100% concentration of TCA should be utilized. The skin should be held taut, and the acid applied directly to the scar using a toothpick or sharp wooden applicator, Dr. Chwalek emphasized. “It’s very important to keep the TCA isolated to the acne scar – if it spills out to the surrounding area, this may result in a potentially larger scar for the patient,” she explained. Higher concentrations of TCA have been shown to be more effective at modifying deeper scars, and typically result in greater patient satisfaction with no significant complications, she added.
Frosting will occur at the site of treatment within 10-15 seconds, crusting will be observed 3 days post treatment, and after a week, the site of treatment will be fully resolved. It is crucial to warn darker-skinned patients of the risk of transient postinflammatory hypopigmentation as a result of the CROSS method, although this resolves within weeks of treatment. “It is also important to make patients aware of downtime associated with CROSS,” she added. “One week after treatment, they may still have crusting.”