 Hi, I'm Laura Hansen. I'm in the Neuroophthalmology Department at the Moran. Today we're going to be showing you some of the features of the Neuroophthalmic exam. We're going to start today with the Hardy-Ran Rettler pseudo-isochromatic color plates. This is one way that you can test color vision. The nice thing about these plates is that it can screen for red-green defects and for blue-yellow defects. The Ishiar color plates primarily just screen for red-green defects. So generally you want to examine patients who have an acuity of around 2200 or so. The test starts out with four different control plates. So you want to have the patient test one eye at a time. So can you go ahead? Yeah, that's perfect. We'll test your left eye first. So you ask the patient to describe what they see on the test plate. Zero X. Good. So you go through all four of these. The fourth is a blank plate. And then the next six plates are the screening test. And so again you have the patient test one eye at a time. Ask them to go through each of the plates. Zero X. Just a zero. Triangle. Very good. And then you can do the same thing with the other eye. Okay, so now we're going to be testing for an afferent pupillary defect and we'll talk about how to measure the size of the defect. All you need is a muscle light and some neutral density filters. The one that we have here are in 0.3 log unit increments and we have a 0.3, 0.6, and 0.9. So you're going to start out by asking the patient to focus on something in the distance. You're going to use the muscle light to shine into each eye. And then you do the swinging light test where you go back and forth between the two pupils. An afferent pupillary defect is present if the pupil dilates when the light reaches it again in the swinging light test. So for demonstration purposes I'm going to try to induce an afferent pupillary defect on the left side. So for this instance I'm going to hold the neutral density filter over the left eye. The left eye will perceive less light and the pupil should dilate on the swinging light test. So if you'll just look straight ahead again for me. This is the swinging light test. Instead of constricting on the left side the pupil dilates slightly. I'm going to demonstrate the ocular motility exam. When we do the exam we differentiate between ductions and versions. Ductions are the movements of one eye by itself. Versions are the movement of the eyes together. Usually we just begin with versions and if there is an abnormality then you can add inductions. But I think the easiest way to do it is to have the patient follow one finger. You can do this with both eyes open for versions. And you just ask the patient to follow your finger as you make an H in the air. And you'll bring the eyes through all six cardinal directions of gaze. And as you do that you want to watch the eyes watch for smooth pursuit of your finger. It shouldn't be, the eye should not be jumping back and forth. Once you've done that and you've found that the eye moves normally you can test saccades. So in order to do that you have the patient focus at a target off to the side. I like to use my thumb and then now focus on my nose. Back to my thumb, back to my nose. So that's testing a horizontal saccade as you watch the eye jump between. And then you can test vertical saccades. Look at my thumb, back to my nose, thumb, nose. Alright. For the next part of the exam we'll talk about the alignment of the eyes. So what we do is have the patient focus at a distant target. So can you look at that letter down there? You can see that without your glasses? Yes. Okay. And we usually start out with the cover-uncover test. So this looks for a tropia or a manifest deviation, a deviation that's present even with binocular viewing. So go ahead and look right at the six for me. So you're going to cover one eye and then uncover it. And you watch for movement or refixation movements of each eye. So you cover, uncover. Then you do the other side. Cover, uncover. So her eyes are very well aligned. For the next part of the test we do the cross-cover test which looks for aphoria. That's a latent deviation or one that's only present when you break binocular fusion. So look again at the six for me. So you cover the right eye and then directly switch to the left eye and then back to the right. So you're breaking the binocular fusion. And again you watch for any refixation movements of each eye. This is a prison bar. This is one of the tools that we use in neuroophthalmology to measure deviations. Kind of makes it fast and quick. This is a horizontal prison bar. You can tell because the base is oriented out to the side. In a vertical prison bar the base will be oriented from the bottom portion of each prism. And so if you're looking to measure a deviation you point the apex in the direction of the deviation. You hold it over one eye and if you want to measure aphoria you do the cross-cover test adding increasing amounts of prism until you've neutralized the deviation. For her I'm actually inducing one because she's very well aligned. For the next test we're going to do the Maddox rod. Thank you I have an assistant here. The Maddox rod is a series of cylinders. You can have the patient orient them vertically which will give you a horizontal red line. Or you can have them oriented horizontally which gives vertical red line. The idea is that you give the eyes two very dissimilar images. And so you can very precisely measure the deviation. So let me have you hold that up over the right eye. And you have your assistant hold a muscle light down at the end of the room. So can you appreciate that there's a horizontal red line when you're looking through your right eye? Yep and you can kind of rotate that to make it perfectly parallel with the floor. Okay so when you're looking down at the white light above or below the red line. Or right on. So she's very well aligned. So the light and the line are at the same level. So now we're going to turn your head. So this is measuring her in left gaze. So go ahead and look back at the light. Is the light above or below the red line? It's right on it. Right on it. So perfectly aligned there. And how about there in right gaze? Right on it. Very good. You can also do it in down gaze. Exactly on it. And up gaze. Okay I'm going to show you how to measure the deviation with the Maddox rats. Let me again have you hold that up there. So she's very well aligned but for argument's sake let's pretend that she had a vertical deviation. So let's pretend that the white light is above the red line. So you can use a vertical prism bar and add more prism since the white light is above. I'm going to give her, I'm going to be correcting a left hypodeviation. But you add increasing prism until the patient tells you that the white light and the red line are perfectly aligned. Okay. I'm going to show you now how the neural ophthalmologist use the Hurtel X ophthalmometer to measure the position of the globe within the orbit. So this is the Hurtel. These are the index points. These are the mirrors and this is the ruler that you use to measure the base. So what you want to do is take the index points and we like to put them just inside the temporal orbital rim just slightly inferiorly to the lateral canthus. So while the patient is positioned that way, you close one eye, look in the mirror and you'll see two red lines. The points of the red lines are to eliminate parallax. So you line those two up when you're taking the measurement. You look in the mirror and you can see the corneal apex. And so you just use one eye open, ask the patient to look at your open eye and you mark in your head where the corneal apex falls. You do the same thing on the other side and you always want to make sure that you take the base measurement. This is the distance between the two index points. So today we've reviewed some of the techniques for color vision testing, APD testing, the ocular motility exam, and the alignment exam. I hope you found this tutorial helpful.