Treatment of nevus of Ota by Q switched Nd : YAG laser: a histologic and histometric study

[摘要] Background  Nevus of Ota is a dermal hamartoma that presents as bluish/slate gray pigmentation along first or second branch of trigeminal nerve. Patients search for treatment early in life due to psychological trauma and cosmetic disfigurement. The establishment of high power, short pulse Q switched (QS) lasers has provided a tool for substantial therapeutic advances in the management of dermal pigmented lesions. Objectives  The aim of the present study was to correlate the clinical efficacy of QS Nd : YAG laser with histological, as well as histometric findings through studying the quantitative changes of dermal melanocyte surface area in nevus of Ota patients after treatment. Patients and methods  Twelve patients with nevus of Ota were subjected to multiple treatment sessions with 1064 nm QS Nd : YAG laser at 2 months interval accomplished over a period of 2 years. Skin types treated included phototypes III and IV. All patients were photographed before, after each session and at the end of treatment. Skin biopsies were taken from all patients before treatment and after six sessions to perform histological and histometric analysis. Results  Excellent improvement was noticed in four (33.3%) patients, good improvement in five (41.6%) patients, and one (8.3%) patient showed fair response. While, poor response was seen only in two (16.7%) patients. Hematoxylin and eosin and Fontana-Masson stained sections showed significant decrease in the number of elongated spindle-shaped dermal melanocytes throughout the dermis. Meanwhile, histometric study revealed significantly decreased dermal melanocyte surface area after treatment. Conclusion  QS Nd : YAG laser is an effective and easy-to-perform treatment in cases of nevus of Ota in Egyptian patients with minimal side effects. Histological and histometric findings correlated with the clinical improvement attained.

[学科分类] 皮肤病学

[关键词] histometry;histopathology;nevus of Ota;Q switched Nd : YAG laser