When should lasers be used to treat melasma? Mildred López Piñeiro, M.D. provides her insight in our new column on energy devices.
"Lasers should be used... only after a rigid topical regimen has been tried," writes Mildred López Piñeiro, M.D. (Lavizzara - stock.adobe.com)
Melasma is a commonly acquired disorder of hyperpigmentation that affects women at a higher percentage compared to men.1 It is a multifactorial skin condition triggered by sun exposure, hormonal changes, systemic illnesses, medications and genetic susceptibility. Treatment of melasma has been traditionally centered on the use of daily sunscreen and topical bleaching creams or chemical peels.
However, given the broad absorption spectrum of melanin, a variety of lasers and light sources have also been investigated with some success. These studies include the use of the Intense pulsed light (IPL), ablative (ABL) and non-ablative fractional lasers (NAFL), QS 1064 nm, QS 694 nm and picosecond devices.2 Also, there is recent evidence to suggest a vascular component to melasma, and, therefore, improvement in melasma has been achieved combining the PDL with other therapies that mainly target hyperpigmentation.
IPL has wavelengths ranging from 515 nm to 1200 nm, which is thought to be beneficial in the treatment of melasma as it can target both epidermal and dermal pigment. Studies in 2011 by Goldman et al. demonstrated a 23% improvement when IPL was used alone vs. a 57% improvement when IPL was used in combination with topical therapy. Similarly, in 2012, Figuereido et al. showed a 49.4% improvement using IPL in combination with topicals, with a sustained
improvement of 44.9% at 12-month follow-up. Interestingly, in 2008, Li et al. reported >51% improvement with four consecutive IPL sessions. In their study, this was particularly highlighted in patients with predominantly epidermal melasma who had Fitzpatrick skin types I-III, which is important to consider when applying it to clinical practice.
Fractional lasers create microthermal zones of controlled skin damage that result in more rapid skin recovery as well as a reduced risk of serious complications such as scarring. Both NAFL and ABL technologies have been tested for the treatment of melasma. I will focus on the 1927 nm wavelength as it has been more extensively studied specifically for epidermal and superficial dermal hyperpigmentation.3
The pilot study for this device in melasma was completed by Polder et al. who showed a 51% improvement one month following three to four treatments with fluences of 10 mJ to 20 mJ, and 34% improvement at six months following completion of all treatment sessions. A longer retrospective study in 2013 by Niwa Massaki et al. looked at females who had undergone a single treatment with the 1927 nm NAFL at uences of 10 mJ to 20 mJ with 60-70% surface area coverage and assessed their response at one month, six months and 12 months. All patients pursued maintenance therapy with topical hydroquinone one month after the laser session. The study reported 50% improvement by one month and continued improvement up to 53.8% at six to 12 months follow-up. This suggests a more durable response with a single treatment session. However, it does not replace the requirement to be consistent with topical therapies.
Q-switched lasers provide a short pulse duration with a higher energy intensity. QS lasers that target melanin include the Ruby, Alexandrite and Nd:YAG. Initial studies were somewhat disappointing as the majority of patients experienced significant post-inflammatory hyperpigmentation and worsening melasma. A newer technique called low fluence QS laser is now being studied at the 1064 nm wavelength, with promising results.4 Wattanakrai et al. found an improvement of 92.5% after five consecutive weekly sessions with the low fluence QS Nd:YAG in a split face study. However, hypopigmentation was a common side effect and, unfortunately, there was a 100% recurrence rate. Two separate studies by Xi and Hofbauer Parra have found similar recurrence rates.
More recently, a newer class of lasers called picosecond lasers with even shorter pulse duration have been studied. The thought is that with a shorter pulse duration, there is more of subthermolytic photoacoustic damage that can selectively target pigment without destroying or excessively heating the surrounding tissue.5 There have been only a handful
of case reports using this laser modality in melasma. However, theoretically it seems to represent a potential treatment alternative for melasma with less cutaneous side effects such as dyspigmentation. This could be particularly true if used in combination with topical therapy, or if used with a fractionated handpiece for combination with laser-assisted drug delivery of a variety of bleaching agents.
In conclusion, melasma is a notoriously hard-to-treat condition. The treatment should be personalized to each individual. The most successful approaches tend to rely on the combination of sunscreen, lightening topical products (hydroquinone, tranexamic acid, kojic acid, glycolic acid, retinoic acid, superficial chemical peels), laser/light therapy and, sometimes, even oral tranexamic acid. In our practice, we use IPL, low fuence 1927nm and picosecond treatments with variable success. However, the decision of whether to laser is still up for argument - given the high recurrence rates and the lack of blinded studies - lasers should be used as second line therapy only after a rigid topical regimen has been tried.
1. Sarkar, R, et al. Melasma in Men: A Review of Clinical, Etiological, and Management Issues. J Clin Aesthet Dermatol. 2018 Feb;11(2):53-59
2. Sarkar, R, et al. Lasers in Melasma: A Review with Consensus Recommendations by Indian Pigmentary Expert Group. Indian J Dermatol. 2017 Nov-Dec; 62(6): 585–590
3. Kim EH, et al. The vascular characteristics of melasma. J Dermatol Sci. 2007;46:111–116
4. Trivedi MK. A review of laser and light therapy in melasma. Int J Womens Dermatol. 2017 Mar; 3(1): 11–20
5. Liu T. Photoacoustic generation by multiple picosecond pulse excitation. Med Phys. 2010 Apr;37(4):1518-21