Let's talk more about chalazions, and this
is noninfectious, so it's going to be swelling
typically the upper eyelid again, and it's due
specifically to blocking of the Meibomian gland.
Okay, you're saying, okay, I know you talked
about that, but what's a Meibomian gland?
Well in fact, Meibomian
glands sit up there in the tarsus
and they're going to make a
modified sebaceous secretion
that's going to help to keep the
front of the eye relatively moistened.
That Meibomian gland though, that sits
up there within the tarsus can become,
the products of that can be blocked
and then you'll get this swelling behind it.
So it's inflammation related to
that and in fact, can be confused,
can be actually part and parcel
of blepharitis, posterior blepharitis.
Okay, so it may be a very subtle distinction,
you shouldn't worry too much about it, but
chalazion specifically are due to blockage of the
Meibomian gland that sits up there in the tarsus.
So it's usually painless.
It's firm, it's kind of rubbery consistency,
it's because of all the material
It's being made by the Meibomian
gland and not getting out from the tarsus
so it just swells and swells and swells.
There is some eyelid tenderness because there
are nerves clearly in the eyelid related to this.
It looks inflamed.
It's a little bit erythematous.
The eyelid will feel heavy.
Yeah, it should, because it's filled up with this
sebum that's being made by the Meibomian gland
and there will be increased tearing and again, because
probably of involvement of the lacrimal gland laterally.
So that's what we're talking about.
See the tarsus there and the Meibomian
glands that line that inner portion of the tarsus
and they, that outflow into and
around the eye gets blocked.
So that's what goes on with the chalazion.
Things that can cause this, the
etiologies, so again, poor lid hygiene,
chronic blepharitis, particularly posterior blepharitis
where eyelid trauma or surgery or viral conjunctivitis,
all those can block the outflow of
the sebum from the Meibomian glands.
There are a variety of things
that can happen systemically
and you can read them as well as I can read them.
They're lesser causes overall of chalazion.