Pulsed Dye and Copper Bromide Lasers

The vascular lasers were used to treat melasma with variable results. There are not enough good scientific reports to confirm the role of vascular laser and copper bromide lasers for the treatment of melasma at present.

The basis for the role of vasculature in melasma was reported by Kim et al. It was shown that melasma lesions have, in addition to increased pigmentation, more elasto- sis and vascularization than perilesional skin. Chromometer measurements were significantly higher in the melasma lesion than the nonlesional skin. Histology showed that factor VIIIa-related antigen staining showed a significant increase in the number and size of dermal blood vessels in the lesional skin. Added to the significant relationship between the number of vessels and pigmentation, expression of vascular endothelial growth factor (VEGF) was significantly increased in melasma skin [31, 32].

16.2.9.1 Pulsed Dye Laser (PDL)

Pulsed dye laser was reported to improve the topical treatment outcome of melasma and prolong remission period. Passeron et al. carried out a controlled, randomized, single-blind, split-face clinical trial evaluating the effectivity of dual treatment of fixed triple combination cream (TCC) and PDL in the treatment of melasma. Patient satisfaction was significantly greater for the combination treatment. Half of the patients with dark skin type IV developed PIH. PDL in association with a bleaching cream appears beneficial in treating melasma in patients with skin phototypes II and III [33].

Following the same study, Passeron reported that melasma lesion treated with PDL and triple cream showed long remission indicating enhanced effects of PDL on melasma lesions [34].

16.2.9.2 Copper Bromide Laser

The copper bromide laser (Dual Yellow; Norseld) is a laser with a concomitant- output dual-wavelength light source comprising 90 % yellow light at 578 nm targeting vascular lesions and 10 % green light at 511 nm which targets pigmentary lesions. These two light wavelengths can be emitted separately or simultaneously. Recent studies have suggested the potential effectiveness of targeting the vascular component of melasma [33, 34, 35, 37].

In a recent pilot study, ten Korean women with mixed or epidermal melasma were treated with a copper bromide laser emitting both wavelengths simultaneously at

2-week intervals for a total of 8 weeks. MASI scores decreased modestly from an average of 12.3 pretreatment to 9.5 at 1-month posttreatment follow-up. Using a chromometer, the authors noted measurable lightening of lesional skin after treatment, but the effects appeared to wane slightly at 1-month posttreatment follow-up. The same findings were seen when erythema was measured. Clinically, three patients were noted to have recurrence at the 6-month posttreatment follow-up. The histologic examination of lesional skin before and 3 months after treatment showed decreased levels of basal layer melanin (Melan-A) and fewer melanosomes in the epidermis after treatment, suggesting some longer-term benefit. In addition, CD34 staining for blood vessels showed a decrease in the number and size of dermal vessels after treatment. Staining for endothelin 1 and VEGF antigen showed decreased numbers in keratinocytes posttreatment, indicating some effect of the laser on vascularity within treated lesions. It is significant to note that none of the ten patients exhibited scarring or dyspigmentation from treatment. The authors concluded that the copper bromide lasers seem relatively safe and at least moderately effective for melasma in Asian patients (level of evidence, II-iii). Additional studies in other patient populations will help determine the generalizability of these results [35].

A study done in Thailand, however, did not corroborate these positive results. Among 20 melasma patients treated with the copper bromide laser, the mean melanin index (MI) showed no statistically significant improvement compared with baseline measurements at any of the follow-up visits. Though there were significant improvements in clinical evaluation after three treatments (p = 0.00), this difference was no longer visible after six treatments. There was no improvement as measured by clinical evaluation or MI. The authors concluded that copper bromide laser does not improve melasma in patients with skin phototypes III-V [36].

Ghorbel et al. from France conducted a randomized split-face study comparing copper bromide lasers with the triple cream (a combination of hydroquinone, 5 %;

dexamethasone acetate, 0.1 %; and retinoic acid, 0.1 %). All patients applied the topical cream to their entire face once a day for 4 weeks. A hemiface was then randomly assigned to be treated with the copper bromide laser, while the other side of the face continued to receive daily application of the topical cream for 3 additional months. Four sessions of copper bromide laser were given at weeks 4, 6, 9, and 12. The yellow and green wavelengths were simultaneously produced at a ratio of 9:1. The treatments’ effectiveness was assessed using the MASI score for each hemiface. Follow-up visits were conducted at 3 and 6 months. The main evaluation criterion was the patient’s MASI score 6 months after the end of treatment. At the end of treatment, the topical cream resulted in a greater decrease in the MASI score compared with the laser treatment (p=.006). The MASI score at 6 months was comparable with the score at the beginning of the study in both groups; no significant difference was observed between the two groups. No difference could be found when results were analyzed according to the localization and duration of the melasma (p > .99 and p=.87, respectively). An increased vascularization was noted on the melasma lesions at baseline compared with perilesional skin. However, no decrease in vascularization was observed on the laser- treated side between the baseline and posttreatment visits. At the final visit, no changes in vascularization were noted between the two sides. Neither scarring nor PIH was noted. The authors concluded that results showed that Kligman’s formula combination cream is more effective than the copper bromide laser for treating melasma [37].

It would appear that there is little role for the copper bromide laser in the treatment of melasma since the latter two reports appear to indicate lack of superiority over topical treatment. The role of other vascular lasers remains to be ascertained.

 
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