Welcome back to neuropathology.
Here, we’ll take a look at
We’ll walk through the
most common conditions,
and then as we journey
through this further,
we’ll get into more
It’s important that you pay
attention to the definitions
and pay attention to what
is the underlying cause of
the particular demyelinating disease.
We’ll begin our discussion by
looking at multiple sclerosis.
And when you say multiple
you should be thinking that
this one of the most common
demyelinating diseases that
you shall see in the U.S.
The second thing that you want to do
is pay attention to the definition.
the two major components in this
paragraph that are important to you
is the separation into time
and the separation in space.
The next question you want to ask yourself
is, what is being separated in time?
And that would actually be
the neurologic defects.
So anytime that the patient
is suffering from,
let’s say a relapsing course
or a neurologic defect,
how much time is there in
between in terms of intervals?
And then secondly, what
does space referring to?
It’s referring to the actual demyelination,
or in other words,
the physical pathologic destruction
that’s taking place of the white matter,
and that would be
separated by space.
The operative words here: time and space,
time referring to
and the space referring to the
degeneration of the white matter.
The clinical course is here.
Now, one that’s the most common
in terms of clinical course will be,
and I’ll walk you through this quickly,
but the one that I’ll
spend a little bit more
time with will be the
top graph that you see,
the top graph.
And by this, we mean that there’s
going to be a relapsing and remitting
type being the most
The X axis, the horizontal line,
represents the time course;
meaning to say, in general,
the age of the patient.
The Y axis represents the
or the severity of the disease.
So, the higher you go, the
more severe is the disease.
Now, you’ll notice, please,
that the top graph represents
a most common pattern,
which is the relapsing and remitting
progression of multiple sclerosis.
So you’ll notice that you’ll
have a spike ever so often
but you’ll have a steady increase
in severity of the disease itself.
So over the age of the individual,
as the person is getting older,
they would have time in which
they are going to remission,
which is then still a steady
progression, but still,
every time that they’re having relapse,
it seems as though that the
disease is a little bit worse.
So maybe initially, there might
be a little bit of blurring and
and what we call optic neuritis
and visual disturbance,
and then it goes away for a little bit.
Then it comes back.
When it comes back,
now there might be
issues with some kind of
and then it goes back into
remission, and so on and so forth.
An overall theme for all the
graphs here are exactly that.
Age on the X axis and then you have the
severity of the disease on the Y axis.
The most common pattern is
going to be the top first one
in which we see a steady,
and deterioration of
your nervous system.
Now, we have secondary progressive,
may have superimposed relapses.
And so therefore, if you take a look
at this with secondary, which is the
second graph from the top,
we have what’s known as your secondary
progressive or secondary type of relapsing.
You’ll notice here that
in terms of progression,
that it’s not a steady deterioration
over the course of time or age.
But you’ll notice that there is,
let’s say relapsing and remission
type of a condition or behavior,
and then all of a sudden, take a look at
the very, very right end of this graph.
You’ll notice that there’s, all
of a sudden, a steady progression
abruptly and spontaneously.
This is the very characteristic
of secondary progressive.
And then you have primary progressive.
And this, just to be quick here, will
be the third graph from the top,
and you’ll notice that you do not have such
a remitting and relapsing type of course,
that you have just a
These are the ones that are less common
in terms of clinical presentation to you.
And the one that you will pay attention
to most in this section of clinical course
will be the first bullet point,
which correlates with
the first top graph.
Once you’ve understood that and you
take a look at the bottom two graphs,
then you had the third one
in which, here once again,
it’s unpredictable progression
So, there might be remitting,
relapsing, and so on and so forth,
but honestly, it’s
That is all that I wish to say about the
bottom most graph in this discussion.