Spectroscopic Characterization of Color Polymorphism in the Orbital Skin

Abstract

The color and shape of the orbital skin have specific properties, differing from those of the cheek and forehead. Changes in the properties of the orbital skin are recognized as so-called “dark circles.” To understand the variety in the color and shape of the orbital skin, we previously observed the orbital skin in 180 healthy females, and found color tone characteristics (brown, red, and blue) and various morphological characteristics. We also established a photographic scale for their scoring and reported the results of the analysis of their correlation with age at the 48th Conference of the SCCJ. In this study, to clarify the association of skin color tone with melanin and regional blood flow, analysis of skin properties by non-invasive spectroscopy and assessment by scoring using the photographic scale were performed in 60 healthy females. The brown tone score was positively correlated with the melanin index. This suggested that the brown tone in the orbital skin is due to melanin. The red tone score was positively correlated with the Hb value and negatively correlated with the blood flow rate. These results suggested that the red tone in the orbital skin is due to increased Hb and blood flow stagnation. The blue tone score was negatively correlated with oxygen saturation and blood flow, suggesting that the blue tone in the orbital skin reflects blood flow stagnation and decreased skin circulation. These results suggested the important role of regional blood flow, and changes in melanin content play important roles in changes in the color tone of the orbital skin.