In the April 2013 issue of the Journal of Drugs in Dermatology (2013;12:428-431), Clark et al retrospectively reviewed 115 laser sessions with the 1550-nm erbium-doped fractional nonablative laser (Fraxel Re:Store SR 1550, Solta Medical) in 45 patients with Fitzpatrick skin types IV to VI to assess the rate of postinflammatory hyperpigmentation and the associated laser parameters. The fluence, treatment level, and number of passes were all reviewed, as well as any posttreatment complications (ie, erythema, blistering, edema, bruising, pain) and long-term (1 month) complications (ie, hypopigmentation, hyperpigmentation). All patients were pretreated with hydroquinone cream 4% 2 weeks before, stopping 7 days before treatment and then continuing 4 weeks thereafter. Also, continuous forced-air cooling was used during treatment as well as posttreatment ice packs. Fifty-eight percent (26/45) of treatments were performed in patients with Fitzpatrick skin type IV, 24% (11/45) with type V, and 18% (8/45) with type VI. Laser parameters ranged from 4 to 70 mJ, treatment level 2 to 9, and 4 to 8 passes. Of 115 sessions, 5 (4%) were associated with postinflammatory hyperpigmentation; 2 of these instances occurred in 1 patient. The occurrence of postinflammatory hyperpigmentation was found to be statistically significant (P=.05), correlating with higher mean energy levels compared to those without hyperpigmentation (60.8 vs 44.7 mJ). Only 1 episode of postinflammatory hyperpigmentation lasted longer than 1 month, and 2 of 5 cases had only transient (<7 days) hyperpigmentation. All 5 cases resolved.
What’s the issue?
The 1550-nm erbium-doped fractional nonablative laser is being used for many skin conditions and has a low incidence of adverse effects when appropriate laser parameters are chosen. When treating darker skin phototypes with this technology, the concern for postinflammatory pigmentary alteration is more concerning. Higher treatment densities used in darker phototypes have been associated with a greater risk for postinflammatory hyperpigmentation. In their review, the authors showed that higher energy levels were associated with their cases of postinflammatory hyperpigmentation, with the caveat that they were careful not to use higher density or treatment levels than they would have used in lighter phototypes. Importantly, all 5 cases of hyperpigmentation did resolve and only 1 lasted longer than 1 month (2 months in total). This analysis reinforces that the 1550-nm erbium-doped fractional nonablative laser is quite safe in Fitzpatrick skin types IV to VI when appropriate parameters are utilized, as well as methodical pretreatment and posttreatment with hydroquinone, concomitant cooling, and strict posttreatment sun protection. With the right parameters, the treatment is quite safe; however, what are the optimal treatment parameters to provide efficacious and lasting results?