*Anterior blepharitis occurs at the outside front edge of the eyelid where the eyelashes attach.
*Posterior blepharitis affects the inner edge of the eyelid that touches the eyeball.
<br>See also :
* [[Chalazion]]
* [[Stye]]
==Symptoms==
People with blepharitis may experience a gritty or burning sensation in their eyes, excessive tearing, itching, red and swollen eyelids, dry eyes or crusting of the eyelids. For some people, blepharitis causes only minor irritation and itching. However, it can lead to more severe symptoms, such as blurring of vision, missing or misdirected eyelashes, and inflammation of other eye tissue, particularly the cornea. By touching and rubbing the irritated area, a secondary infection can also result. By touching and rubbing the irritated area, a secondary infection can also result.
*Ulcerative blepharitis patients have matted, hard crusts around the eyelashes. Removing the crusts leaves small sores that ooze and bleed. These patients may also experience eyelash loss, distortion of the front edges of the eyelids and chronic tearing. In severe cases, the cornea (the transparent front covering of the eyeball) becomes inflamed.
*Meibomian blepharitis patients have a blockage of the oil glands in the eyelids, poor quality of tears and redness of the lining of the eyelids.
==Causes==
* Anterior blepharitis is commonly caused by bacteria (staphylococcal blepharitis) or dandruff of the scalp and eyebrows (seborrheic blepharitis). These bacteria are commonly found on the face and lids, but if they become excessive, or the lid area reacts poorly to their presence, an infection may occur. Less commonly, allergies or a mite infestation of the eyelashes can cause anterior blepharitis.