What does milia refer to in dermatology?

Milia refer to small, white cysts that typically appear on the surface of the skin, particularly around the eyes, cheeks, and forehead. These cysts are characterized by their lack of visible openings, which distinguishes them from other types of cysts. Milia occur when keratin, a protein found in the skin, becomes trapped beneath the outer layer of skin, leading to the formation of these tiny, hard bumps.

Their closed nature is significant as it impacts how they are treated; unlike cysts with visible openings, which may drain easily, milia often require professional extraction for removal, or they may resolve on their own over time. Understanding this aspect of milia helps in proper identification and management within the field of dermatology and skincare.