What is it?

A chalazion is a chronic sterile inflammatory injury (like a cyst) caused by an oily secretion retained primarily by the Meibomian glands found inside the eyelids. When a chalazion is secondarily infected it is known as internal sty. It can occur at any age and on a recurring basis, and is more common in patients with meibomian pathology or rosacea.

What are the symptoms?

It is usually a painless lesion, but can cause pain if it is inflamed. In very occasional cases a large upper eyelid can press on the cornea causing astigmatism and blurred vision.

Treatment

Treatment may be unnecessary because at least one third of the cases resolve spontaneously, and an internal sty may also disappear.
When there are alterations of the glands, with multiple lesions or recurrence of the same, more specific treatments are required with drops or ointments (lubricants and sometimes anti-inflammatory and antibiotic), eyelid massage with heat and food supplements with omega-3.
Persistent encysted injuries that cause discomfort or aesthetically are not accepted by the patient require surgery for removal or a small injection of corticosteroids in the same lesion especially if it is near the lacrimal punctum.