Our Focus
Blepharitis is a common ocular condition, characterized by inflammation of the eyelid, which can impact the anterior or posterior lid or both.
People with anterior blepharitis typically have red, irritated, or itchy eyelids with debris on the eyelashes.
Blepharitis affects at least 20 million Americans and is one of the most common reasons people visit an eye doctor.
It can be caused by multiple factors including infestation of Demodex mites. Demodex mites are the most common ectoparasite found on humans. There are two species of Demodex – folliculorum and brevis – that live on the skin of the face and eyelids.
While they are highly prevalent in low numbers, it is an infestation of Demodex folliculorum mites that is implicated as a cause of blepharitis in 45% of cases.
Demodex Infestation Can Cause Disease in Three Main Ways:
Mechanical
Overcrowded mites scrape the epithelial cell lining with their claws and lay eggs in the follicle causing follicular distention, misdirected lashes, madarosis and irritation. Dead mites and collarettes also obstruct the hair follicle opening, leading to inflammation.
Chemical
Mites excrete digestive enzymes as they feed and exude digestive waste when they die causing inflammation, hyperemia, irritation, and epithelial hyperplasia.
Bacterial
Bacteria living on the mite surface or in its gut cause inflammation of the surrounding ocular tissues.
Demodex Blepharitis can be diagnosed when collarettes, a pathognomonic sign of Demodex infestation, are seen with a routine slit-lamp exam.
See How Demodex Mites Cause Disease
Currently, there are 2.1M blepharitis diagnoses per year, but no FDA approved treatments.
If left unmanaged, Demodex Blepharitis may lead to tear film instability with fluctuating and blurred vision, lid and lash abnormalities, inflammation of the conjunctiva and surrounding skin, suboptimal surgical outcomes, contact lens intolerance and reduced wear time, noticeable eye and eyelid redness, and lower patient quality of life.
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