So we're going to go ahead and
perform the fundoscopic exam.
but first, let's orient
ourselves to our ophthalmoscope.
So what we're going to be
doing is direct ophthalmoscopy.
If you've ever been to see an eye
doctor, they do indirect ophthalmoscopy.
And I think if you've ever been to
and actually had that exam performed,
you know that an indirect ophthalmoscope is not
something you can carry around in your pocket.
It's a big, it's a whole contraption.
Whereas this, of course, you
can carry around in your pocket.
I'm going to talk about two different
types of direct ophthalmoscope.
This is the more traditional one.
But I also have here a panoptic, which
I'm going to review in just a moment.
So, in terms of what the different
parts of the ophthalmoscope are,
of course the first thing to do is push the green
button and rotate in order to get your light.
So that gives you the amount of
light that you're going to be using.
And keep in mind that when you're deciding
how much light to shine out of the aperture,
you're deciding if you use too much light, the
patient's pupils will be a bit more constricted
and also it can be uncomfortable for the patient.
So sometimes you want to start with
a somewhat dimmer light in order to
to locate where you want to be in the
eye and get in the right position.
And then you can turn it up when you really
want to see things well before time "runs out",
when the patient becomes uncomfortable.
Next up, we'll take a look at the specific.
This dial right here, which dictates the
aperture that we're projecting light through.
So the default setting is
typically a medium sized dot here,
and this is sort of what we
would start off with usually.
Then you can rotate this dial and
get a larger or a smaller view,
depending upon whether the patient's eyes
have been dilated or not pharmacologically.
Then typically you also have this little
grid that can sometimes help to identify
the four quadrants of the retina,
as well as relative distances
of particular findings that you may discover.
This is your modified slit lamp.
Of course, it's nothing like a slit lamp that
you would get in an ophthalmologist's office,
but it can nonetheless be useful for
assessing the contour of the cornea
when you're looking for corneal
abrasion or some other types of defects.
And this is your well, it's on my blue coat and
difficult to distinguish this, it's a green light,
but it's essentially a red light filter.
And by using this one, you can actually
highlight or bring out more contrast
when you're looking at red blood
vessels in the back of the eye.
Right. So I'm going to go to my default setting.
And the last thing to point out,
of course, is this carousel.
And this is basically where you are
adjusting the lens on your ophthalmoscope
based on your own prescription, whether
or not you are nearsighted or farsighted,
and whether the patient also, if you're looking at
their eye and they're nearsighted or farsighted,
that's going to affect your your view as well.
And usually there's a default setting that
you can dial to where it just says zero
and you'll dial it up or down based
on once you start performing your exam
and having shown you that, this is where the
panoptic actually can be particularly useful.
So I'm going to switch over now.
So, again, the panoptic, let's see, has, of course,
the same base, so I'm going to dial up my light,
dial it up or down in the same fashion.
It defaults to a green line here, which is
similar to on my traditional ophthalmoscope.
That's my simply white circle
of medium sized circle.
And I will go through the same sequence here.
So medium sized circle.
and then I have my red light filter,
and then my slit lamp there.
But the real advantage of this is this
carousel here is a continuous wheel
and interestingly enough, using
the panoptic ophthalmoscope,
once I've adjusted it once for myself, for my
own degree of near-sightedness or farsightedness,
it does not need to be
modified based on the patient,
except in rare circumstances if the patient
is profoundly nearsighted or farsighted,
you may need to make a small adjustment.
The way to get it set for yourself is you
simply pick a spot on a wall about 10 feet away,
taking my glasses off because it's easier
for me to look without my glasses on
and once I bring that area
into view, into full focus,
and in this case, you can actually sort of see where
where it ended up based on my own farsightedness.
I can leave that at that position and
I shouldn't really have to change it,
regardless of the patient that I'm examining
which is why the panoptic is advantageous,
not to mention the fact that it is a larger
field of view when you use this ophthalmoscope.
Having done that, let's talk
about patient positioning.
This is one of the more challenging
parts of the physical exam,
and you want to make sure that both you and
the patient are as comfortable as possible,
because if I'm not quite at
the same height as she is,
if she's higher than me on the on the
examination table or if I'm taller than her,
it ends up being a little bit
trickier to get into focus.
And also, if I'm not comfortable where I'm seated
or standing, if I'm rocking around back and forth,
sort of doing my own Rhomberg
test, that's not going to be very
conducive to getting a good image as well.
So it's important to make sure
that we're about at the same level.
And then we're going to have you do Shayla is
just look off towards that camera over there
and hold your thumb out in front of your eye.
Now that she is looking at this, I'm going
to go off from there by about 15 degrees
and we'll dim the lights and then we're
going to take a look for the light reflex.
The red light reflex, which
tells me that I'm on target.
Okay, so having her focus on her
thumb right out in front of her,
I'm going to go about 15 degrees off from that.
Now, you can go ahead and put your thumb down now.
Just make sure you kind of
look off in that direction.
And the first thing I'm looking for is
a red light reflex, and that tells me
that I have an unobscured view from my
ophthalmoscope to the back of her retina.
If a patient had a severe cataract, then of
course, that may obscure the red light reflex.
And then I'm just going to slowly move in.
I usually put my hand just gently on the shoulder
just to make sure I'm oriented where she is,
and I like to then just make contact with
the little rubber stopper on the end.
Great, and then what we're looking for is.
The optic disc.
and the cup.
And then you're going to look around to
the peripheral vessels as best you can.
And if you can just look towards the light briefly.
Great. That's it.
So now, just to highlight some of the
specific things that I was looking for
when I was doing the fundoscopic exam,
you are looking at the disc to cup ratio.
The cup is the smaller circle in the
middle where the vessels are coming out.
And then the disc is the larger area.
Usually the cup to disc ratio should be about
1:3 but there are circumstances like glaucoma
where that cup can get enlarged and that may be
a harbinger of intraocular pressure problems.
In addition, you want to look at the actual
border of the optic disc and how sharp it is.
Patients with a blurred optic disc
may have evidence of papilledema
from a variety of causes in terms of
intracranial hypertension versus optic neuritis
would also have evidence of papilledema.
And then looking out into the
periphery of the visual fields,
you're looking at some signs of either diabetes
or hypertensive retinopathy with AV nicking,
cotton wool spots, flame hemorrhages
and less commonly, Hollenhorst plaques.