Blepharitis

Blepharitis: Blepharitis (eye lid inflammation) is closely associated with dry eye. Dysfunction of the lipid (oil) producing meibomian gland, located in the eyelids, is almost always a factor. There are three primary types of blepharitis:

• Obstructive. This is characterized by hyperkeratinization (hardening) of the eyelid margin and meibomian gland orifices, with thickening of the lipids secreted by the meibomian glands. Patients exhibit dry eye symptoms that include low tear flow and a high tear evaporation rate.
• Seborrheic. Patients with seborrheic dermatitis (skin inflammation elsewhere on the body) often exhibit seborrheic blepharitis as well, with increased lipid production. These individuals develop dry eye more frequently than the normal population, probably as a result of hormonal feedback from surface inflammation.
• Bacterial. Bacterial overgrowth on the eyelid margin causes inflammation and contributes to hyperkeratinization, resulting in meibomian gland obstruction.