Track

Abstract

In the United States, the representation of skin of color in dermatology and studies involving non-invasive imaging technology has historically been lacking. To address this gap, our research focuses on qualitatively describing the natural variations in all human skin types in vivo, utilizing Line Field Confocal Optical Coherence Tomography (LC-OCT). Our prospective observational study employed LC-OCT to analyze healthy skin across various phototypes and anatomical areas, including the forehead, mid-back, and left dorsal forearm. Twenty participants, with a median age of 24.4 years and dermascopically normal skin, were recruited during routine dermatology clinic visits. Fitzpatrick phototypes ranged from I/II to V/VI. For each participant, LC-OCT 3D images were obtained, and quantitative measures such as stratum corneum thickness, viable epidermal thickness, dermo-epidermal junction (DEJ) undulation, keratinocyte nuclei (KN) mean volume, KN mean compactness, and KN network atypia were collected. Statistical analysis revealed no significant differences among phototype categories and anatomical locations for stratum corneum thickness, viable epidermal thickness, and mean KN compactness. However, DEJ undulation increased notably in the temple (p=0.005) and midback (p=0.00092) areas, along with an increase in mean KN volume (p=0.017) and KN network atypia (p=0.014) in the midback. These findings challenge the misconception that darker phototypes inherently possess thicker skin. Moreover, they highlight the role of DEJ undulation which is known for maintaining skin homeostasis and providing a conducive environment for epidermal stem cells. Further research is warranted to explore the clinical implications of these morphological characteristics and their influence on clinical outcomes.