, results from a combined systematic review and meta-analysis suggest.
Dr. Marcus G. Tan
“Microneedling has a similar efficacy to other drug delivery methods, such as CO2 laser or intradermal microinjections, for the treatment of melasma,” presenting author Marcus G. Tan, MD, said during a virtual abstract session at the annual meeting of the American Society for Dermatologic Surgery. “When used in combination with topical depigmenting therapies, microneedling also demonstrated superior efficacy and a more favorable safety profile compared to oral tranexamic acid.”
For the study, Dr. Tan, a 5-year dermatology resident at the University of Ottawa, and colleagues searched MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials using the keywords “melasma” and “microneedling.” They limited their analysis to prospective, comparative studies incorporating the use of microneedling in the treatment of melasma and excluded those involving radiofrequency. The primary outcome was improvement in melasma severity, evaluated through the Melasma Area and Severity Index (MASI). The secondary outcomes were improvement in patient satisfaction, quality of life, and any reported adverse events.
Twelve studies involving 459 patients from seven countries were included in the final analysis. Of these, seven were randomized controlled studies and five were nonrandomized split-face studies. Topical treatments used in the studies included tranexamic acid (TXA), vitamin C, platelet-rich plasma, and hydroquinone-based depigmenting serums such as rucinol, sophora-alpha, and N-acetyl glucosamine. Of the 12 studies, 4 used mechanical microneedling and 8 used electric repeating microneedling. The most common needle length used was 1.5 mm, with a range from 0.1 to 1.5 mm, depending on the anatomic site treated. Topical anesthesia was applied 30-60 minutes prior to treatment. Treatment intervals were 2-4 weeks apart.
Their analysis found that microneedling alone resulted in a 23%-29% improvement in MASI. “Across all studies, adding topical therapies resulted in greater improvements in melasma severity, with a moderate effect at 8 weeks and a large effect at 12-16 weeks,” Dr. Tan said. “This also translated to higher patient satisfaction scores and improved patient-reported quality of life.”
A split-face study in the analysis, which compared topical TXA with microneedling to topical TXA with fractional CO2 laser, found that both approaches had similar efficacy and rates of adverse events. Another split-face study that evaluated recalcitrant melasma found that adding vitamin C with microneedling to a nonablative Q-switched Nd:YAG laser resulted in a further 38.3% greater improvement in MASI and a 12.5% lower recurrence rate at 6 months.
In two other studies, researchers compared microneedling to intradermal microinjections to deliver platelet-rich plasma or topical TXA. Both modalities were found to have similar efficacy. “However, microneedling was found to be better tolerated and had higher patient satisfaction as a result,” Dr. Tan said.
A separate analysis found that Tri-Luma (fluocinolone acetonide, hydroquinone, and tretinoin) cream with microneedling outperformed Tri-Luma plus oral TXA in terms of efficacy, patient satisfaction, and tolerability. “Interestingly, adding oral TXA to Tri-Luma with microneedling did not lead to further improvements,” Dr. Tan said.
The researchers found that microneedling was well tolerated in all 12 studies. Overall, no scarring or serious adverse events were reported. Mild-transient dyspigmentation occurred in 5%-12% of cases and herpes simplex virus reactivation was seen in a minority of patients.
Dr. Tan commented on three proposed mechanisms of action, which support the efficacy of microneedling for the treatment of melasma. “First, microneedling assists in the transcutaneous delivery of topical agents through the micropores,” he said. “Second, microneedling also assists in the transcutaneous elimination of melanin and other skin debris through the micropores. Third, the microinjuries stimulate the wound healing response, resulting in neocollagenesis, neoelastogenesis, and epidermal thickening.”
In an interview, Dr. Tan acknowledged certain limitations of the study, including the pooling of randomized and nonrandomized studies in the final meta-analysis, the heterogeneity in the treatment protocols and devices used, as well as the inclusion of studies with a moderate risk of bias. “Nonetheless, these limitations do not affect the conclusion that microneedling is a useful and safe adjuvant to topical therapies for melasma,” he said.
Catherine M. DiGiorgio, MD, who was asked to comment on the study, noted that melasma is a notoriously difficult condition to treat. “Many energy-based device treatments as well as other therapies have been proposed for treatment over the years. However, none have shown reliable, reproducible, and most importantly long-lasting results,” said Dr. DiGiorgio, a laser and cosmetic dermatologist at The Boston Center for Facial Rejuvenation. “Caution should be employed regarding the true efficacy of treatments for other than, at best, temporary results.”
Dr. Catherine M. DiGiorgio
The review included numerous studies without a clear definition of the strengths or methodologies of the studies, she added, noting that randomized controlled split-face studies with long-term follow up are the best way to assess the efficacy of treatments. “Further, regarding drug delivery, microneedling is the least effective method of delivery of drugs to the skin and laser-assisted drug delivery using ablative fractional lasers is the most effective. As with all melasma treatments, healthy skepticism is never a bad approach.”
Dr. Tan reported having no financial disclosures. Dr. DiGiorgio disclosed that she conducts research for Quthero Inc., and holds stock in the company.