Korean J Dermatol.  1996 Dec;34(6):961-967.

Treatment of Ota's nevus with the Alexandrite Laser

• Kang HJ
• Hahm JH

Abstract

BACKGROUND: Recently, Q-switched lasers have been reported to be successful in treating Ota's nevus without scarring. Utilizing the principle of selective photothermolysis, the Alexandrite laser has been developed for dermal pigmented lesions and tattoos.
OBJECTIVE
In this study, we evaluated the clinical, histopathological and ultrastructual effect of the Alexandrite laser in the tretment of Nevus of Ota.
METHODS
Forty-seven patients with nevus of Ota were treated with energy densities ranging from 5.0 to 8.0 J/cm2 at a miriimum of 6 week intervals. Sequential skin biopsy specimens were processed for the light microscope with H&E and Fontana-Masson stains and the electron microscope.
RESULTS
The average number of treatments were 2.8 per patient. After two treatment sessions, 93 % patients 26 to 75% imprivement was seen. After three treatments 50 to 95% improvement was seen. No patients had permanent textual changes or scarring. On light microscop most of the dendritic melanocytes in the upper dermis were not observed in biopsy specimens taken after clinical improvement. Electron microscopy revealed damaged melanosomes in the upper dermis immediately after irradiation.
CONCLUSION
Treatment with the Alexandrite laser for nevus of Ota is considered to be a safe and effective method.

Keyword

Alexandrite laser; Nevus of Ota

MeSH Terms

Biopsy
Cicatrix
Coloring Agents
Dermis
Humans
Lasers, Solid-State*
Melanocytes
Melanosomes
Microscopy, Electron
Nevus of Ota*
Skin
Coloring Agents