ABSTRACT
OBJECTIVES: Melasma is an acquired type of hyperpigmentation that is characterized by the appearance of scattered light- to dark-brown macules and patches on the face. Recently, several lasers have been proposed as treatment options for melasma. In particular, the picosecond alexandrite laser is an ideal laser for selective photothermal melanolysis. The aim of our study was to compare the effectiveness in melanolysis of a single treatment of the picosecond alexandrite laser with that of the Q-switched Nd:YAG laser using reflectance confocal microscopy imaging of the melasma lesions. MATERIALS AND METHODS: We performed a spilt-face study using the picosecond alexandrite laser and Q-switched Nd:YAG laser in eight patients with melasma. Both melasma lesions and surrounding normal skin were examined under reflectance confocal microscopy 1 and 24 hours after treatment. The melanin intensity of each skin layer was investigated. RESULTS: At baseline, melasma has irregular melanin distribution and a higher melanin density than surrounding normal skin under reflectance confocal microscopy. After a single treatment with either the picosecond alexandrite laser or the Q-switched Nd:YAG laser, both melanin-induced reflectance and melanin index decreased. CONCLUSION: Our findings suggest that it is feasible to assess the distribution of melanin by reflectance confocal microscopy and observe the melanolysis in melasma lesion after laser treatment. Lasers Surg. Med. 51:423-429, 2019. © 2018 Wiley Periodicals, Inc.
ABSTRACT
Various hyaluronic acid fillers can be used for facial attenuation and rejuvenation. The efficacy and durability of hyaluronic acid fillers are of major concern to dermatologists and patients. This study aimed to evaluate three-dimensional morphology, tissue distribution, and changes in volume after injection of two different hyaluronic acid fillers. Ten Korean women were enrolled in this study. Each subject was injected with monophasic hyaluronic acid filler in one malar area and biphasic filler in the other. Clinical outcome was measured before and after injection, and after 2, 4, 6, 8, 12, and 24 weeks, using the Global Aesthetic Improvement Scale, photographs and Moire's topography. Facial magnetic resonance imaging (MRI) was performed twice over six months. Both products showed good results after injection and demonstrated good durability over time. MRI was a useful modality for assessing tissue distribution and volume changes. The effects and durability after injection of monophasic hyaluronic acid filler and biphasic hyaluronic acid filler are generally comparable.
