What is a chalazion and how is it different from a stye?

16 December 2021

When we talk about chalazion we refer to a bulge on the eyelid, which arises when a fat gland is blocked. You may not notice it at first, but as the chalazion grows, the eyelids may become red, swollen, and sometimes tender to the touch.

A stye is a small, red, painful bump that grows at the base of the eyelashes or under the eyelids. Most are caused by bacterial infections and there are two types:

• External stye: begins at the root of the eyelashes; most are caused by infections of the hair follicles and can resemble a pimple.

• Internal stye: grows on the inside of the eyelid; most are caused by an infection of the fat-producing glands of the eyelid.

Sometimes it is difficult to distinguish a stye from a chalazion, however, its main difference is that the stye is very painful, usually swollen and sometimes affects the entire eyelid. Meanwhile, the chalazion is usually painless and generally develops further back on the eyelid than a stye. It is due to a blockage in the sebaceous glands and rarely causes swelling of the entire eyelid.

Among the symptoms of the stye we can find:

• Very painful red bump on the edge of the eyelid and at the base of the eyelashes.
• It causes swelling of the entire eyelid.
• Possibility of having pus in the center of the lump.
• Foreign body sensation in the eye
• Itchy eyes
• Sensitivity to light
• Tearing

Chalazion usually has no symptoms, here are some possibilities:

• A bump on the eyelid. In some cases it turns red and swollen.
• In rare cases, the entire eyelid may swell.
• If the chalazion is large enough to put pressure on the eyeball, you may have blurred vision.