Therapeutic Update on Acne Scarring

as assessed by both subjects and physician evaluators with no significant difference in efficacy between the devices. The Fraxel re:store was noted, however, to be significantly (P<0.001) more painful than the E-matrix (mean of 7.75 on a 10-point scale vs 5.90).

One of the cornerstones of acne scar treatment is the use of dermal fillers. Fillers are generally most effective on shallow, rolling scars and ineffective on ice pick scars. HA fillers such as Juvederm (Allergan, Irvine, CA) and Restylane (Medicis, Scottsdale, AZ) can be used as monotherapy or in combination with subcision to raise atrophic acne scars. As always, one advantage of the HA fillers over more permanent fillers is their reversibility in the event of over-correction or patient dissatisfaction. Although HA fillers are not permanent, there is some evidence to suggest that the mechanical effect of placing the HA stretches dermal fibroblasts leading to neocollagenesis and a more sustained, long term effect.¹⁴ Belotero (Merz Aesthetics, Greensboro, NC) may be particularly well-suited to treat acne scars because of its low G’, low viscosity, and zones of high and low density that allow the material to insinuate into areas of scarring. Of note, simply stretching the skin with tumescent saline can offer some degree of improvement and may be a cost-effective way for patients to “preview” the effect of dermal fillers prior to committing to the procedure.

One of the first fillers to be utilized in cosmetic dermatology was silicone. While many have abandoned the use of silicone due to safety concerns, others continue to champion the use of pure, medical-grade silicone as an effective and safe treatment for acne scars. Data regarding the use of silicone for acne scars is limited to case series, the largest of which was published by Barnett in 2005 where he reports his experience using silicone for over 30 years in several thousands of patients. He reports that he has had no major adverse events with only minor bleeding and bruising at the injection site and fewer than 10 patients with over-correction of scars.¹⁵ Silicone must be administered using a micro-droplet technique over a series of several sessions to avoid over-correction. This is in contrast to HA in which the final degree of correction is, for the most part, appreciable before the patient leaves the office.

Artefill^® (Suneva, San Diego, CA) is a long-lasting dermal filler comprised of 20% polymethylmethacrylate (PMMA) microspheres suspended in 80% bovine collagen that was FDA approved in 2006 for the correction of nasolabial folds. While the collagen is absorbed over time, the microspheres remain as a scaffold for the development of new collagen and are large enough such that there is no migration from the site of injection. The effects of Artefill remain for approximately 5 years or more. Suneva Medical announced in 2013 that its multi-center, industry-sponsored clinical trial of the use of Artefill for acne scars met its endpoints for efficacy with statistical significance. They plan to seek an FDA approved indication for the use of Artefill for acne scarring, and if successful, would be the only on-label filler for acne scarring on the market. Two concerns regarding the use of Artefill include the need for skin testing prior to administration (because it contains bovine collagen) and the risk of granuloma formation. According to the manufacturer’s guidelines, the skin test site must be observed for 4 weeks after placement, which may be a deterrent for patients seeking treatment on or soon after the day of their consultation. True granuloma formation is virtually unheard of with the third-generation product and was exceeding rare (1:5,000) even when using the second-generation product Artecoll.¹⁶ It is believed that what might be perceived as “granulomas” are actually nodules of product that form as a result of being placed too superficially.

One of the latest trends in dermal fillers is the use of autologous fibroblasts in which the patient’s own fibroblasts are harvested from post-auricular punch biopsies, cultured, and then injected into contour defects. Theoretically, the use of living cells has the potential to provide a longer-lasting, dynamic treatment effect compared to that obtained using an inert, artificial substance. Similarly, autologous fibroblasts offer a treatment alternative for patients who are seeking “natural” therapies or who are “allergic to everything.” A multi-site, prospective, double-blind, split-face, placebo-controlled trial of 99 subjects with distensible acne scars demonstrated treatment success (defined as a two-point improvement on a 5 point scale) in 43% of subjects versus only 18% in the placebo group as assessed by the subjects¹⁷. Interestingly, the degree of improvement as assessed by the physician evaluator was much more modest: 59% of the treated group met the primary endpoint compared to 42% in the placebo. The results not only emphasize a strong placebo effect in the treatment of acne scarring but also highlight an important clinical correlate, which is that what may seem like a nominal degree of improvement to physicians is potentially a meaningful and life-changing improvement for the patient. Skeptics of the new technology question whether the relative benefit will outweigh the cost, particularly in an era with widely available, highly effective and safe synthetic dermal fillers.

Ice pick and boxcar scars that extend into the fat generally will not respond to dermal fillers or resurfacing techniques. Often the best approach for these unsightly scars is to remove the defect via punch excision and linear closure with subsequent resurfacing. Rather than closing the defect, a punch graft