The lids contain numerous meibomian glands that secrete oils into your tear film. These oils prevent evaporation of your tears, as well as forming a smooth and lubricated surface for clear vision. MGD occurs when these glands are not working properly. The oily secretions produced are of poor quality or the glands become blocked and atrophied. Meibomian gland Dysfunction (MGD) is achronic diffuse abnormality of the meibomian gland commonly characterized by terminal duct obstruction which may result in alteration of the tear film.
Meibomian (“my-BOH-mee-an”) glands are the tiny oil glands which line the margin of the eyelids (the edges which touch when the eyelids are closed). There are about 25 to 40 meibomian glands in the upper eyelid and 20 to 30 in the lower eyelid. The function of these glands is to secrete oils onto the surface of the eye. These oils help keep the tears from evaporating too quickly. The tear film lubricates and keeps the surface of our eyes healthy; it also affects how clearly we see. Pathogenesis of MGD Meibomian gland located in the tarsal plates of the eye lids opens at the posterior lid margin. It is the chief source of lipids for the human tear film and functions in stabilizing the tear film. It forms a protective barrier against microbes, dust and pollen. MGD is an obstruction of terminal ducts. Factors such as age, sex, hormonal disturbances and topical medication influence the obstructive process. MGD results in increased evaporation and instability of the tear film. It increases bacterial growth on the lid margin,evaporative dry eye and ocular surface inflammation.
Although patients often volunteer their ocular symptoms, direct questioning can usually elicit some or all of the following :
- Momentary blurriness clearing with repeated blinking
- Transient foreign body sensation
- Paradoxical watering / epiphora
- Short reading duration because of discomfort
- Constant awareness of the eyes.
- Dry feeling eyes
- Distress from being unable to achieve any ocular comfort or relief
Careful examination of the lids, lid margins and pre-corneal tear film is necessary to appreciate all the signs of MGD but more florid disease can be seen easily without slit lamp biomicrosopy. Signs you may see are :
- Champagne / lemonade bubbles as lid margin froth
- Abnormally thick viscous Meibomian secretions
- Turbid white or yellow cloudy material can be expressed from orifices
- Inspissated secretions with „pointy‟ solidified proud ends
- Glandular obstruction with masking or loss of orifices
- Capping of orifices with „pseudo-blisters‟
- Vascularised lid margins
- Macerated soggy lid edges
- Collarettes of debris around lashes
- Crusty debris at lid margin
- Conjunctivalisation of the posterior margin of lid
- Keratinisation of the lid margin with obfuscated MG orifices
There are a number of ways in which MGD can be treated. It is best however, to use a combination of these methods in order to control and manage your MGD.
- Warm compress therapy: Warm compress therapy is a technique designed to unblock the meibomian glands, restoring them to normal health. This needs to be done at least once (though preferably twice) a day. Rest a heat pack over the eyelids for a few minutes. This will ‘melt’ the oils and help unblock the glands. With your finger or warm washer, gently massage the upper and lower lids in the direction towards your eye. Repeat this procedure a couple of times; ensuring the washer or heat pack remains warm.
- Lid scrubs: If associated with blepharitis (inflammation of the eyelids), lid scrubs, such as SteriLid or LidCare will need to be used to clean the lid margins of infection and debris.
- Bicarbonate of soda eyewash: An eye bath of 1 teaspoon bicarb soda in half litre of boiled water, which is to be kept in refrigerator in clean screw top container and replaced every second week. The eyewash can be used with either an eye bath, cottonwool or cotton buds. The refrigerated solution must be kept clean and therefore a portion of the solution should be tipped into a clean glass each day with the remainder being kept refrigerated in screw top bottle.
- OptiMel Manuka Honey: Applying antibacterial manuka honey to the lid margins twice a day with a cotton bud kills and prevents accumulation of bacteria along the lid margin. This will minimise the severity of the condition and reduce symptoms.
- Ocular lubricants (artificial tear supplement): These drops ensure there is a sufficient coating of tears across the eye, preventing further dryness complications.
- Omega 3 and Flaxseed oils: In addition to other health benefits, flaxseed oil and Omega-3 fatty acids (2000mg/day) will improve the quality of the meibomian gland secretions. Strict compliance with a lid care regime is crucial. It may however still take 1-2weeks before an improvement is noticed. Symptoms will return if treatment is ceased.