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Modelling and analysis of skin pigmentation
Published in Ahmad Fadzil Mohamad Hani, Dileep Kumar, Optical Imaging for Biomedical and Clinical Applications, 2017
Ahmad Fadzil Mohamad Hani, Hermawan Nugroho, Norashikin Shamsudin, Suraiya H. Hussein
Pigmentation disorders are disturbances of human skin tone, either loss or reduction, which may be related to loss of melanocytes or the inability of melanocytes to produce melanin or transport melanosomes correctly. Pigmentary problems can be divided into two—those that are hyper-pigmented due to either increase in melanin (melanotic) or melanocytes (melanocytic), and those that are hypo-pigmented due to decrease or the absence of either melanin (hypomelanotic) or melanocytes (melanocytopaenic). Table 4.1 shows different types of pigmentation disorders.
Drug-induced hyperpigmention
Published in Dimitris Rigopoulos, Alexander C. Katoulis, Hyperpigmentation, 2017
Pigmentation disorders include a large number of heterogeneous conditions that are usually characterized by altered melanocyte density, melanin concentration, or both, and result in altered pigmentation of the skin. Some of these disorders are extremely common (melasma and vitiligo), whereas others are rare. In this contribution, we review the most common pigmentation disorders that appear on the face. These lesions, even though mostly asymptomatic, have a great impact on a patient’s quality of life.
Skin pigmentation improvement with resveratrol microemulsion gel using polyoxyethylene hydrogenated castor oil
Published in Drug Development and Industrial Pharmacy, 2023
Lu Cao, Xiaoyan Li, Jing Zhao, Qing Du, Jiening Dun
Changes in skin pigmentation are often recognized as indicators of skin exposure to damaging agents, such as those caused by air and other pollution or radiation from electronic and electrical equipment [1]. Some previous studies suggested that the increase in skin pigment is related to the increase of epidermal cytochrome caused by pigment incontinence, the increase of melanin and melanocyte levels in the basal cell layer, and the increase of melanin particles and melanophages in the superficial layer of the dermis [2]. Melanin, which is produced in epidermal melanocytes, is a light-absorbing polymer produced by oxidation catalyzed by tyrosinase. Its production process is influenced by various signaling pathways. In addition, melanin is important in protecting skin from ultraviolet (UV) radiation damage [3]. However, abnormal melanin production can lead to many skin diseases, such as melasma and freckles, caused by melanoma and pigmentation disorders [4,5]. Thus, it is of great clinical value to study and develop drugs that can inhibit the formation of melanin in treating abnormal pigmentation.
Efficacy of a laser with a pulse duration of 300 ps in skin rejuvenation and treatment of pigmentation disorders in Asians: a series of four cases
Published in Journal of Cosmetic and Laser Therapy, 2021
Jie Hoon Kim, Soo Eun Jung, Yun Hwa Park
The first case was PIH, which was treated with laser toning for 4 months, and it was confirmed that the pigment area became bright (Figures 1b and 2b). For the treatment of PIH, nanosecond Q-switched ruby and Q-switched Nd:YAG lasers have been the most widely used (10). Hydroquinone-containing topical therapy is routinely combined with lasers to treat pigmentation disorders as it improves clinical results and patient satisfaction compared to lasers treatment alone. In case 1, a topical agent was used to induce better results as hyperpigmentation had not improved with light-based treatment. Based on this, it is difficult to attribute the entirety of the result to the picosecond laser, as the effects of topical agent may have also played a role in the resolution of the patient’s PIH lesions. However, cases of successful PIH treatment using picosecond lasers have been reported; although further research is needed to clarify the effectiveness and natural healing potential after picosecond laser therapy, these lasers may be an effective treatment option for PIH (11).
An emerging technology in lipid research for targeting hydrophilic drugs to the skin in the treatment of hyperpigmentation disorders: kojic acid-solid lipid nanoparticles
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2020
Khadijeh Khezri, Majid Saeedi, Katayoun Morteza-Semnani, Jafar Akbari, Seyyed Sohrab Rostamkalaei
Pigmentation disorders are one of the most common skin diseases that are caused by abnormal distribution, structure and function of melanocytes. The pigmentation disorders’ treatment has always been challenging and discouraging for the most population especially women. The most middle-aged women have often abnormal pigmentation on their facial skin and these skin disorders are related to various endogenous and exogenous agents [4]. Pigmentation disorders can be expressed in two forms of skin pigmentation increase (hyperpigmentation) and decrease (hypopigmentation). These skin pigmentation disorders can cause aesthetic, cognitive and psychological challenges for the patients and have psychosocial effects on them. Common typical pigmentation disorders including melasma (chloasma) and ephelides (freckles) are related to disturbance in skin pigmentation [5–7].