Dark circles, better described in the medical vocabulary as idiopathic hyperchromia of the orbital ring, correspond to the alteration of the coloration of the skin located under the eyes due to an excessive production of melanin and to the dilatation of the capillaries close to the surface of the skin.
These changes usually occur due to the increase in melanin and changes in the small spider veins that irrigate the area, but it is also known that factors such as tiredness and the sun can cause them.
These alterations usually follow the anatomy of the orbicular muscle of the eyes surrounding the orbit. The pathogenesis is unknown. Some authors consider it as a physiological phenomenon with daily fluctuation but the truth is that the concurrence of several factors is included, including dermal melanocytosis and post-inflammatory hyperpigmentation, although it is usually the result of multifactorial processes.
Many times they are usually secondary to insomnia, or associated with diseases such as sarcopenia (consumptive syndrome) with loss of periorbicular connective tissue.
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