noun. each of the short curved hairs growing on the edges of the eyelids, serving to protect the eyes from dust particles
noun. the mite that lives among your eyelashes
Demodex mites naturally occur on the skin in small amounts and can actually be beneficial for the skin, as they remove the dead skin cells. In small numbers, they typically do not cause any harm or symptoms.
However, if they reproduce in large numbers, they can cause significant damage to the skin and eyes— dry, red, and itchy skin, and/or eczema, as well as severe inflammation of the eyelids, and damage to the oil glands in the eyelid margins, meibomian glands and eyelashes.
noun. a common condition that causes inflammation of the eyelids
Blepharitis is characterized by redness, swelling, styes, cysts, and flaky crusts at the eyelid margin and along the lash line. Symptoms also include scratchy, swollen, tender, and irritated eyes.
Various types of bacteria can cause blepharitis. It may be chronic or acute in presentation. People with skin conditions such as rosacea, acne, and eczema are more prone to have flare-ups. Poor facial hygiene can also be a contributing factor.
There are various types of this condition. Anterior blepharitis occurs on the outside of the eye. You may see redness, swelling, and possibly crust near the line of the eyelashes. Posterior blepharitis happens near the inside of the eyelid where it contacts the eye and can be due to problems with the lubricating meibomian glands inside the eyelids. Both forms of blepharitis require treatment to maintain appearance and eye comfort.
noun. a slimy, sticky film of bacteria that coats a surface
Bacteria are survivors, and they have done so for eons with their evolving survival skills. In nature, most bacteria exist not as free-floating individuals but rather as highly organized communities called biofilms. A biofilm is composed of a well-hydrated matrix of bacteria and their glycocalyx, a sugary coating that allows cells to adhere to and communicate with each other. This protective armor is highly difficult to penetrate–even by antibiotics, surgical iodine prep and, believe it or not, human white cells.
We propose that these bacterial survival skills are the very factors that cause dry eye disease.
Biofilms can form on any surface that provides moisture and nutrients. The eyelid margin—with its moisture, nutrients and warmth—is the perfect environment to cultivate a thriving bacterial biofilm. In fact, it would be unrealistic to suggest that a biofilm does not exist on the lid margin. A biofilm probably begins forming just after birth when the lids become colonized with bacteria.