Blepharitis
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Overview
Plain-Language Overview
Blepharitis is a common condition that affects the eyelids, causing them to become red, swollen, and irritated. It involves inflammation of the eyelid margins where the eyelashes grow. This condition can lead to symptoms such as itchiness, burning, and a feeling of grittiness in the eyes. People with blepharitis often notice crusting or flaking around the eyelashes and sometimes experience watery eyes or sensitivity to light. Although it is usually not sight-threatening, blepharitis can cause significant discomfort and may affect daily activities involving vision.
Clinical Definition
Blepharitis is a chronic inflammatory disorder of the eyelid margins characterized by inflammation and irritation of the eyelid skin and associated structures. It is commonly caused by dysfunction of the meibomian glands leading to altered lipid secretion and bacterial colonization, often involving Staphylococcus aureus or Propionibacterium species. The condition is classified into anterior (affecting the eyelid skin and eyelashes) and posterior (involving the meibomian glands) types. Clinical significance includes chronic discomfort, eyelid margin erythema, scaling, and potential complications such as chalazion, hordeolum, or secondary conjunctivitis. The pathophysiology involves a combination of bacterial overgrowth, gland dysfunction, and immune-mediated inflammation.