00:01
Hello and welcome to the congenital thyroid
pathology that we need to refer to.
00:07
Just enough information to make sure that
you’re able to distinguish one condition
from another.
00:12
Think of this as being an enlargement that
you’re going to find in the neck.
00:16
Here, you have a picture of a child that has
such an enlargement.
00:23
Highly differential could be something like
a thyroglossal duct cyst.
00:26
However, as we continue our discussion, we
will further look at other differentials that
you want to keep in mind and either rule them
in or rule them out.
00:35
To begin, the thyroid-thyroid development,
it is the back of the tongue known as a foramen
cecum.
00:41
It is then migrating down towards…
Where you would expect your thyroid gland
to be?
The beautiful isthmus that you know as being
the thyroid.
00:51
However, anywhere along the migration from
the foramen cecum and down to where the thyroid
should be located and if there’s a remnant
may then be referred to as being a thyroglossal
duct cyst.
01:04
As the fibrous tract, which is the obliterated
thyroglossal duct and extends from the pyramidal
lobe and that is an important anatomical landmark
that you want to pay attention to superiorly
to the hyoid bone and may harbour thyroglossal
duct cyst anywhere between those regions.
01:29
Now, when you have such a remnant remaining,
is it possible that you may have altered thyroid
function?
No.
01:39
You’d have normal thyroid functioning, just
as you would with normal thyroid, depending
as to exposure.
01:46
Is it possible that you may then develop cancer
in thyroid gland?
Sure.
01:52
Could then the thyroglossal duct cyst, which
is a remnant of your thyroid, may give rise
to an ectopic thyroid cancer?
That is a possibility.
02:01
Keep that in mind.
02:03
Careful examination of the anterior cervical
region for identification of the pyramidal
lobe superiorly to avoid leaving residual
thyroid tissue is an important step to assure
a total thyroidectomy has been completely
and adequately performed.
02:23
It is important that you at least know the
significance of that pyramidal lobe and that
this is not just a transient or trivial piece
of information.
02:35
Ectopic thyroid tissue can be found anywhere
along the path from the foramen cecum, back
of the tongue, down towards it should be by
the hyoid bone.
02:45
It does not alter thyroid function, but, as
I mentioned earlier, can give rise to ectopic
thyroid cancers.
02:53
Let’s take a look at differentials.
02:57
A dermoid and sebaceous cysts are tethered
to the underlying tissue, whereas when you
have a thyroglossal duct cyst upon deglutition,
you are going to find this to be moving.
03:13
Branchial cleft cysts are associated with a
sinus tract or fistula.
03:18
Differential, this is a branchial cleft cyst,
usually associated with the sinus.
03:24
That’s something that you want to keep in
mind.
03:27
Lipomas are superficial, have ill-defined
edges.
03:32
In other words, you’re thinking about subcutaneous
tissue and fat with the lipoma.
03:38
Or if your patient is suffering from, let’s
say, some type of infection, may then result
in lymphadenopathy cervical and salivary gland
tumours would be other differentials that
you want to keep in mind whenever you find
enlargement in the neck region.