Histopathologic, Immunohistochemical, and Electron Microscopic Findings of Pigmented Skin Lesions Immediately after Q-switched Alexandrite Laser Treatment.
- Author:
You Chan KIM
1
;
Won Hyung KANG
;
Dongsik BANG
;
Na Hae MYUNG
;
Chung Ku RHEE
Author Information
1. Department of Dermatology, Dankook University, College of Medicine, Cheonan, Korea. kyccc@dku.edu
- Publication Type:Original Article
- Keywords:
Electron microscopic;
Pigmented skin lesions;
Q-switched alexandrite laser
- MeSH:
Biopsy;
Cytoplasm;
Dermis;
Epidermis;
Humans;
Lasers, Solid-State*;
Melanocytes;
Melanosomes;
Nevus;
Skin*
- From:Korean Journal of Dermatology
2003;41(8):1014-1021
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: There have been only a few electron microscopic studies after laser treatment of pigmented skin lesions. OBJECTIVE: The purpose was to investigate the pathologic, immunohistochemical, and electron microscopic changes following Q-switched alexandrite laser treatment of pigmented skin lesions. METHODS: Three patients with acquired bilateral nevus of Ota-like macules, and 2 patients with cafeau lait macule were irradiated with Q-switched alexandrite laser. Forty biopsies were taken before and immediately after laser treatment. Hematoxylin-eosin, Fontana-Masson, and gp100 staining were performed for the evaluation of the histopathologic and immunohistochemical findings of the specimens. Electron microscopic findings were also evaluated. RESULTS: Histopathologically, suprabasilar separations were observed immediately after laser treatment. Vacuolar alterations of pigment-containing cells were frequently found in the epidermis and/or in the dermis. Fontana-Masson and gp100 staining positivity changed to negative or decreased in the epidermis immediately after laser treatment, while they changed to negative in the dermis. Ultrastructurally, epidermal pigment-containing cells frequently showed severe vacuolar changes in the cytoplasm, pyknotic nuclei, and vacuolated and/or fragmented melanosomes immediately after laser treatment. Dermal melanocytes frequently revealed vacuolated and/or fragmented melanosomes immediately after laser treatment. CONCLUSION: Histopathologic, immunohistochemical, and electron microscopic examination of pigmented skin lesions immediately after Q-switched alexandrite laser treatment demonstrated vacuolated or fragmented melanosomes and vacuolar alteration of pigment-containing cells in the epidermis and/or in the dermis, which suggested selective photothermolysis of melanosomes.
