Blepharitis, or chronic inflammation of the eyelid, is the most common ocular disease known. The symptoms of blepharitis include redness of the eyes and eyelids, itching, burning and a feeling that something is in the eyes. Some patients complain that their eyelids form crusts and stick together in the morning. Blepharitis always involves the eyelid margin (edge), but in some cases it may also affect the conjunctiva (inner lining of the eye), cornea (clear outer layer of the eye) and eyelid skin.
Adults are affected more often than children. The condition may occur at an increased frequency within certain families and in children with Down’s syndrome.
What are the types of blepharitis?
To better understand this condition, think of the eyelid as being composed of two layers, one in front of the other. Each of these layers contains unique structures whose function may be affected by blepharitis.
Anterior blepharitis is related to inflammation of the front layer of the eyelid. The symptoms usually are limited to ocular itching, burning and irritation. Although there are many possible causes of anterior blepharitis, it is most often related to bacterial infection or seborrheic dermatitis, a chronic inflammatory skin condition.
Seborrheic dermatitis is a common problem affecting the scalp, eyebrows, face and eyelids in two-thirds of anterior blepharitis patients. It is the most common cause of blepharitis. This condition leads to oily secretions, eyelid swelling, scaling and flaking produce ocular itching and burning that can be severe. Both layers of the eyelid may be affected.
Posterior blepharitis occurs when the small (meibomian) glands in the inner layer of the eyelid either become inflamed or secrete an excessive quantity of their normal product. These glands produce an oily substance, an important part of the normal tear film that bathes the surface of the eye. Overproduction of this substance can produce a bothersome burning sensation of the eyes, although the eyelids may remain normal in appearance. In contrast, patients suffering from gland inflammation may also complain of a burning sensation as well as tearing, itching, irritation, sensitivity to light and crusting upon awakening in the morning. In these patients, the eyelid margin may appear red and swollen. The cause of gland inflammation is unknown, but bacterial infection or plugging of the glands by abnormally thick secretions is thought to play a role.
Treatment of blepharitis
Blepharitis is a chronic condition. Treatment involves thorough eyelid cleansing aimed at keeping the eyelid margin free from crusts and secretions. Both anterior and posterior blepharitis are treated with warm compresses (warm, moist wash cloth applied to the eyelid) followed by lid cleansing (using a moist cotton swab to gently clean the eyelid margin) two to three times each day. For posterior blepharitis with significant meibomian gland dysfunction, some physicians may recommend treatment with oral antibiotics. Blepharitis is a difficult disease to treat and a complete cure is not easily achieved. Effective treatment requires a long-term commitment from both patient and physician.
Complications concerning blepharitis
Complications may occur in patients with anterior or posterior blepharitis. In the presence of bacterial blepharitis, an abscess (a collection of pus surrounded by inflamed tissue) may form in the sweat glands or hair follicles normally present in the anterior layer of the eyelid, producing a stye. A stye develops rapidly, producing an elevated, painful, red, swollen area on the eyelid. Styes rarely occur in seborrheic dermatitis, but may occur in up to one-third of patients with posterior blepharitis. Treatment consists of frequent warm compresses and, in select cases, antibiotics.
A chalazion is a firm nodule that may form following either anterior or posterior blepharitis. Secretions from meibomian glands normally present in the posterior layer of the eyelids may leak into the surrounding tissues, causing inflammation. Chalasia may occur suddenly or may appear gradually over time. They may be painful, red, and swollen, or may simply produce a firm mass. Conservative treatment with frequent warm compresses is often successful, but steroid injections into the chalazion or surgical removal are sometimes necessary. In rare cases, cancerous tumors of the eyelid can appear like a stye or chalazion.
“Eye Facts” is an informational series and should not be used as a substitute for medical advice. For eye appointments, call (312) 996-6591. All Eye Facts illustrations and images are copyright protected and are the property of the UIC Board of Trustees. Unauthorized use of the images is prohibited. For usage of any Eye Facts content or illustrations please contact the Office of Medical Illustration at [email protected] or 312-996-5309 for licensing.