Fundoscopic Examination

00:01 So we're going to go ahead and perform the fundoscopic exam.

00:03 but first, let's orient ourselves to our ophthalmoscope.

00:07 So what we're going to be doing is direct ophthalmoscopy.

00:10 If you've ever been to see an eye doctor, they do indirect ophthalmoscopy.

00:14 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.

00:22 It's a big, it's a whole contraption.

00:24 Whereas this, of course, you can carry around in your pocket.

00:27 I'm going to talk about two different types of direct ophthalmoscope.

00:30 This is the more traditional one.

00:32 But I also have here a panoptic, which I'm going to review in just a moment.

00:37 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.

00:48 So that gives you the amount of light that you're going to be using.

00:51 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.

01:04 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.

01:11 And then you can turn it up when you really want to see things well before time "runs out", when the patient becomes uncomfortable.

01:19 Next up, we'll take a look at the specific.

01:21 This dial right here, which dictates the aperture that we're projecting light through.

01:26 So the default setting is typically a medium sized dot here, and this is sort of what we would start off with usually.

01:34 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.

01:45 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.

02:01 This is your modified slit lamp.

02:02 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.

02:16 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.

02:23 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.

02:31 Right. So I'm going to go to my default setting.

02:34 And the last thing to point out, of course, is this carousel.

02:38 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.

02:55 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.

03:12 So I'm going to switch over now.

03:19 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.

03:28 It defaults to a green line here, which is similar to on my traditional ophthalmoscope.

03:33 That's my simply white circle of medium sized circle.

03:37 And I will go through the same sequence here.

03:41 So medium sized circle.

03:50 and then I have my red light filter, and then my slit lamp there.

03:58 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.

04:23 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.

04:45 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.

04:58 Having done that, let's talk about patient positioning.

05:03 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.

05:21 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.

05:32 So it's important to make sure that we're about at the same level.

05:34 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.

05:44 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.

05:53 The red light reflex, which tells me that I'm on target.

05:57 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.

06:02 Now, you can go ahead and put your thumb down now.

06:04 Just make sure you kind of look off in that direction.

06:06 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.

06:15 If a patient had a severe cataract, then of course, that may obscure the red light reflex.

06:22 And then I'm just going to slowly move in.

06:26 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.

06:42 Great, and then what we're looking for is.

06:45 The optic disc.

06:47 and the cup.

06:51 And then you're going to look around to the peripheral vessels as best you can.

06:59 And if you can just look towards the light briefly.

07:05 Great. That's it.

07:10 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.

07:19 The cup is the smaller circle in the middle where the vessels are coming out.

07:22 And then the disc is the larger area.

07:25 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.

07:38 In addition, you want to look at the actual border of the optic disc and how sharp it is.

07:42 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.

07:54 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.