Chalazion (Meibomian Cyst)
A Chalazion (also known as Meibomian Cyst) appears as a lump on the eyelid. A common condition, it is benign and easily recognised and diagnosed. It can be treated either medically or surgically.
The condition typically presents as an inflamed swelling in the eyelid caused by a blocked oil duct (meibomian gland). Each eyelid contains over 25 of these oil secreting ducts (located in the tarsal plates) which open onto the eyelid margin and secrete oil into the tear film, helping to stop tears evaporate. If just one duct gets blocked, oil accumulates and may cause a painful, inflamed lump.
Very rarely, a chalazion may masquerade and in fact be a tumour called a meibomian gland carcinoma or sebaceous cell carcinoma, particularly if the chalazion doesn’t go away with incision and curettage surgery or appears solid at surgery, in which case a biopsy is taken.
The eyelids are examined both macroscopically (naked eye) and with magnification (slit lamp) to determine whether it is an acute or quiet chalazion, whether there is any associated blepharitis or meibomianitis or any other problems.
To decide whether medical or surgical treatment is required, the oculoplastic surgeon will examine the eyelid, both on its skin side and evert it to see its underside. Whilst this is being done, the eyes should be open and the patient looking down. Everting the lid does not hurt. A chalazion has a typical “grey” appearance on the underside of the eyelid which helps to confirm the diagnosis. Particular attention is taken in the examination to exclude a malignant tumour. If there is any doubt, a biopsy is recommended.
An inflamed chalazion may eventually settle with regular application of antibiotic ointment onto the eyelid margin for two to three weeks (sometimes longer) and hot compresses or hot wooden spoon bathing (the heat and massage significantly reduce the inflammation).
If the chalazion persists after medical treatment, surgical treatment is necessary. The surgical treatment of a chalazion is known as “incision and curettage” (I+C), and is performed under local anaesthetic. The procedure involves making an opening in the cyst, cleaning the contents out and resecting a small section of the cyst wall. First, the skin is cleaned. A drop of local anaesthetic is applied onto the eye surface and then further local anaesthetic is injected into the skin above the chalazion.
A small clamp is put in place and the eyelid is everted (some pressure or pulling may be felt, but no pain). A blade is used to incise the chalazion from the underside of the eyelid. In rare cases, a small incision on the outer eyelid may be necessary.
Old inflammatory debris is drained from the cyst and the cavity is curetted. This results in an empty, clean meibomian duct after surgery.
After the incision and curettage procedure, the eyelid is padded with antibiotic ointment for up to 24 hours, with a regimen of ointment application for between five and ten days after surgery.