Meibomian gland dysfunction and blepharitis

There are about 25 to 30 meibomian glands located in the upper and lower eyelids. They normally slowly release oil into the tear film, helping to stop its evaporation – so preventing dry eye.

Blepharitis can be due to an over-reaction to the body’s normal bacteria at the eyelids, a disorder of the meibomian (oily) glands on the lid margins, or can be related to other skin conditions such as eczema or rosacea.

Sometimes the oil in the meibomian glands becomes slightly thicker than normal, which can lead to blockage of the narrow duct which takes the oil from the gland to the tear film. The oil continues to be made and this can lead to filling and swelling of the glands, causing dry eye since the oil cannot reach the tear film. Severe blockage can lead to much enlarged glands (a cyst) or even infection. Microscopic crusts can form at the base of the eyelashes, harbouring bacteria. It is therefore important to unclog the blocked glands, clean away the crusts and try to prevent the glands from becoming blocked again.

All our optometrists are able to offer advice in our dry eye clinics.