Ann Dermatol.  2015 Jun;27(3):340-342. 10.5021/ad.2015.27.3.340.

Changes in Melanin and Melanocytes in Mottled Hypopigmentation after Low-Fluence 1,064-nm Q-Switched Nd:YAG Laser Treatment for Melasma

• Jang YH
• Park JY
• Park YJ
• Kang HY

• KMID: 2352514
• DOI: http://doi.org/10.5021/ad.2015.27.3.340

Abstract

No abstract available.

MeSH Terms

Hypopigmentation*
Melanins*
Melanocytes*
Melanosis*
Melanins

Figure

• 

  Fig. 1 (A) Mottled hypopigmentation developing after laser toning for melasma treatment in a 41-year-old woman with Fitzpatrick skin type IV. Hypopigmented, hyperpigmented (i.e., melasma), and adjacent perilesional normal skin were evaluated. Circles indicate biopsy sites of perilesional normal (left), hypopigmented (middle), and melasma (right) skin. (B) Histopathologic examination showed melanin pigmentation was markedly reduced in the basal layer of lesional skin (Fontana-Masson staining). The number of melanocytes, determined according to microphthalmia-associated transcription factor (MITF) expression, did not differ much between lesional skin and perilesional normal skin or melasma skin. The expression of gp100 was higher in hypopigmented lesional skin than perilesional normal skin or even melasma skin (×200).

• 

  Fig. 2 (A) A 49-year-old woman with Fitzpatrick skin type III presented with typical mottled hypopigmentation after laser toning for 1 year. Circle indicates biopsy sites of the hypopigmented lesion. (B) Lesional skin biopsy showed the complete absence of melanin pigment in hypopigmented skin. However, there was no reduction in the number of melanocytes and rather increased gp100 expression (×200). MITF: microphthalmia-associated transcription factor.

Reference

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