PHOENIX — Educate darker skinned patients who seek treatment for acne scars that there is no remedy to make the scars completely disappear.
"Depending on the patient's skin type, the sensitivity of their skin, and how aggressively you treat them, the risk of hyperpigmentation can be relatively modest, or well over 50%. The expected degree of improvement, on the other hand, even with multiple modalities and multiple treatments, is 40%-50%. I think it's very important to explain that," said Dr. Murad Alam at the annual meeting of the American Society for Laser Medicine and Surgery.
Dr. Murad Alam
Dr. Alam, chief of cutaneous and aesthetic surgery at Northwestern University, Chicago, said that clinicians face certain challenges in treating acne scars in patients of color, including the risk of exacerbation of active acne, risk of focal or diffuse hyperpigmentation or hypopigmentation, risk of nodularity or surface texture change, and risk of minimal effect.
To mitigate risks, Dr. Alam considers oral antibiotics in patients who have any degree of active acne, "even if they get one or two acne pimples once in a blue moon," he said. "If the acne is more than very mild, you may wish to target that as the primary goal and defer treatment of the acne scarring until the acne is under good control."
If the acne is mild, "you can start oral antibiotics at least 1 month before the acne scarring intervention, so they do have something on board to reduce the risk of an acne flare," he said. "You may also consider pretreatment with bleaching agents. I'm personally not that convinced that pre-treatment is that helpful, but post-treatment with bleaching agents is of definite efficacy in mitigating postinflammatory hyperpigmentation."
As for treatment, nonablative resurfacing with mid-infrared lasers, including 1320-nm, 1450-nm, and 1540-nm devices, has been shown to be effective in patients with lighter skin. "This heating process causes collagen remodeling, and can have a modest effect on so-called rolling scars, which can be quite disfiguring," he said.
Another option is ablative resurfacing with non-CO2 fractional lasers such as the 1550-nm laser. "This is one of the most gentle devices in this category, but even so you have risks of postinflammatory hyperpigmentation," Dr. Alam said. "I like to err on the side of being very modest with regard to fluences. It's much better to do more treatments than to push each individual treatment at the risk of having pigmentary abnormalities."
A more aggressive approach is ablative resurfacing with CO2 fractional lasers, which "should be restricted to patients who are of lighter skin type. If they do choose this [modality], they need to understand the significant risk of postinflammatory hyperpigmentation. I would say that virtually every patient of skin of color who undergoes this treatment will have some degree of postinflammatory hyperpigmentation. In some cases they might consider that worth it if it makes their scarring better and if it can be managed after treatment so it eventually goes away."
Perhaps the most beneficial treatment for acne scars in patients of color, Dr. Alam said, is subdermal manipulation.
In one procedure, known as subcision, clinicians insert a needle with a sphere-like tip, often an 18-guage Nokor needle, underneath the skin. "By debriding the underside of the skin, you can cause some of the acne scars to float upward," he explained. "You want to ensure very good hemostasis before doing this—lidocaine with epinephrine—because you want to avoid bruising during the procedure. If done properly, this can result in modest improvement of rolling scars, and it can be done repeatedly."
Dermal fillers can be used as an adjunct. About a month after subcision procedures Dr. Alam considers collagen for fine defects, hyaluronic acid for medium defects, and calcium hydroxylapatite for deeper defects.
The best way to develop a treatment plan for acne scarring, he said, is to assess the patient's commitment to improvement and their tolerance for adverse events.
"How much annoyance and disfigurement are they willing to tolerate?" Dr. Alam asked. "If both of these are low, you might wish to restrict yourself to subcision with or without fillers, because if done properly, that almost eliminates the risk of adverse events like hyperpigmentation, and it does provide some modest improvement with relatively little cost."
If the patient is highly committed to achieving improvement but is wary of adverse events, "then you might consider subcision and fillers, followed by nonablative laser or repeated low energy non-CO2 fractional laser treatments."
In those rare patients with a high tolerance for adverse events, he said, consider CO2 fractional laser treatments "at very modest settings."
Dr. Alam said that he had no relevant financial conflicts.