00:01
Here, we’ll take a look at the differences
of goiter versus nodules.
00:04
By the time we’re done with this section,
you should be able to clearly define the differences
between the two so that you never get confused
on the wards or on your boards.
00:15
Let’s take a look at goiter, defined as
a large thyroid, period.
00:21
Here, in the neck of this patient, a pretty
large thyroid gland.
00:28
Multiple etiologies of goiter including hypo
or hyperthyroidism; could be physiologic,
lack of hormone production.
00:37
What happens if your thyroid hormone is not
coming out?
The feedback mechanism increases TSH from
the anterior pituitary, bombards your thyroid
gland and may result in a goiter.
00:49
If you don’t have iodine, once again, increased
TSH bombarding the thyroid gland resulting
in enlargement.
00:56
Foods… important; goitrogens, drugs that
suppress synthesis of thyroid hormones, enzyme
deficiencies of hormone synthesis… number
of causes of goiter.
01:12
Does not describe the functional status of
the thyroid, that’s important for you to
understand whereas the nodules will.
01:17
So, just because you find a thyroid… a goiter,
an enlargement of the thyroid gland doesn’t
necessarily mean that you have a hyper or
hypofunctioning thyroid, you just know that
there is a pathology.
01:29
If it’s non-toxic, we call that euthyroid;
if it’s a toxic type of goiter, it’s hyperthyroid.
01:37
Stop here for one second.
01:38
Last time we talked about toxic was either
solitary or multi… multitoxic type of goiter,
multinodular toxic and those were the elderly
patients that are presenting with hyperthyroidism…
elderly, nodular.
01:54
Okay, so, when we talk about nodules, this
is interesting.
01:58
With nodules, it means that the… well, this
area within the thyroid gland is either taking
up iodine or it’s not.
02:05
If it’s taking it up and it’s focal, you
call this a hot nodule, focal… focal not
diffused, huh?
Whereas if it’s cold, it’s not taking
up the iodine; it then appears as being black.
02:17
Hot is almost always benign, that’s what
you stick with.
02:19
Cold, however, is extremely concerning and
you’re worried about malignancy, but, but
usually, clinically, it is benign, but of
the two, it’s the cold that you should be
investigating further.
02:32
I’ll show you an algorithm coming up in
which we will then follow… you will follow
these with me so that you can then clearly
narrow as to what steps are necessary so that
you can confirm your diagnosis.
02:43
Only a biopsy can tell definitively whether
your nodule is malignant or benign.
02:49
What you’re seeing here in the neck of this
individual is a normal thyroid gland in which
it is the taking up normal amounts of iodine;
nothing here that is truly pathologic.
03:02
Continue our discussion.
03:04
Now, goiter, chronic enlargement of thyroid.
03:06
Remember, it does not, does not define functioning
and nodule a discrete lump and whether or
not it’s taking up iodine or not will then
determine if it’s hot or cold.
03:17
If it’s cold then definitive.
03:19
Definitive biopsy will tell you if your nodule
is either malignant or benign.
03:24
If frequency of small thyroid nodule detected
by ultrasound is greater than 50 percent;
5 to 10 percent of your nodules may then even
contain thyroid cancer.
03:34
Most patients are asymptomatic unless the
nodule gets so big and the goiter, there is
so much enlargement in the thyroid gland that
you then cause compression effects on the
surrounding structures including the trachea…
dyspnoea; upon the esophagus dysphagia.
03:50
Substernal goiter can be nonpalpable… substernal,
but causes airway obstruction to thoracic
inlet obstruction… that is a very important
point.
04:03
So, substernal, okay, won’t be palpable
for obvious reasons, but is then going to
cause thoracic inlet obstruction.
04:13
Here, we’ll take a look at the clinical
approach at thyroid nodule.
04:18
If the size of the nodule is less than 1 centimetre,
no concerning patients, no concerning risk
factors for the patient including head/neck
radiation or nodule features such as microcalcification.
04:31
If there aren’t any risk factors for the
patient, then your next step of management
over to the right versus, yes, there are no
risk factors then it would be follow-up in
imagery.
04:44
If however there are risk factors, so it is
larger than 1 centimetre or the patient has
a history of having neck radiation or you
find microcalcification, then you check TSH.
04:55
You find this to be low then you move to thyroid
scan.
04:58
Upon thyroid scan, you check to see as to
how much iodine uptake is going to be handled
by that nodule and focally, if you find there
to be uptake, it’s hot.
05:06
Your next step of management, you follow-up
because most likely it will be benign.
05:11
If it’s cold, iodine is not being taken
up, C as in cold, C this is concerning.
05:17
Your next step of management is biopsy with
the fine needle aspiration and maybe perhaps
you find cancer or malignancy… definitive
diagnosis.
05:29
A clear picture is very simplistic view, but
yet very effective for you to approach your
thyroid nodule clinically.
05:40
These arrows that you’re seeing here on
the thyroid scan is showing you those areas
of a thyroid gland that are not taking up
iodine.
05:49
Look at it, it is blending in or camouflaging
with the rest of the picture here whereas
the region of the black that you see is trying
to form the outline or silhouette of the thyroid
gland, but those areas or arrows in this areas
that it’s pointing to is not taking up iodine,
it’s a cold nodule.
06:11
What’s your next step of management?
Fine needle aspiration, definitive diagnosis…
Is it malignant?
Is it benign?