Visual Field Testing – How To Get The Most Out of It | Driving with Dr. David Richardson – Series 2, Ep 5

VIDEO TRANSCRIPT:

Hello I’m Dr. David Richardson. I’m a Cataract and Glaucoma Surgeon in Southern California. And on my morning commute, I like to discuss those things that there’s just not enough time to discuss in the exam room.

So, we’ve been talking about visual field testing, how important it is, how frequently it needs to be done, as well as how they can fluctuate. So clearly given how nobody really likes to do these tests, we want to make sure that each test that’s done is of the highest quality it can possibly be. And there are a number of things that you, as the individual taking the test if you’re watching this because you have glaucoma, as well as the doctors’ staff, can do to ensure that the testing is of the highest quality that it can be.

So, let’s go ahead and discuss that.

So, let’s focus on the things that you can do that you have control of. The first thing that I would recommend is to make sure that you are well rested for your visual field. If you’ve not had a good night’s sleep or let’s say you’re a coffee drinker and you’ve not had your morning Joe, then you’re not going to perform as well as you otherwise would. The visual field test, as we’ve talked about, is rather boring. So, if you’re sleep-deprived, chances are you’re going to start to nod off during the test. And that’s going to result in a poor-quality test. So, make sure that you’re well-rested prior to the day of the exam. And when you’re scheduling the visual field test, try to schedule it on a day when you believe you’ll be able to get rest the night before.

Now the other thing that can be done while you’re taking the test is to focus on the reasons why you’re there you need some motivation in order to continue to take this boring test. And so if you keep in mind that you are there in order to maintain your vision right to detect any vision that that may be lost, then that will motivate you to pay attention to the actual test, rather than start drifting off in your mind to what’s on your grocery list or that fight that you had with your relative the other night. It’s very easy to, kind of, get distracted by your own thoughts given how unexciting the test is, but keeping in mind, the reason you’re there can actually be quite motivating and help bring you back to the visual field test.

Now speaking of focus, it’s very important that you maintain focus on the fixation object. So naturally, when the lights appear, you’ll want to move your gaze to the object that disappeared but you need to resist that urge, it’s very important that during the test you maintain fixation on that object right in front of your vision there.

Now there are also some things that the physician’s staff should be doing to make sure that your visual field is of high quality. And the first thing is that most automated perimeters, the visual field devices that are used in modern practices, work best in a darkened room. Now, this does not mean that the room needs to be pitch black, but in general, the ceiling lights should be off, or at least half of them should be off or dimmed. So that the ambient light is not overwhelming, the screen of a visual field unit. Now, speaking of darkened rooms, it’s likely that you will have come in from a brighter area, either the reception area, the outdoors might be quite bright depending on the time of year and where you live. And it takes some time for the retina to adapt to a lower light situation. So that’s particularly important in those who have glaucoma or even ocular hypertension, just high pressures can make the dark adaptation take longer. So it’s important that you have at least a couple of minutes in this darkened environment before the test actually begins, which usually is sufficient time for you to sit down, have the staff put your information on the field, set up the field, get you positioned so that usually takes a couple of minutes and so that’s usually sufficient, but you do want to have some time to adapt you don’t just want to go from a bright room sit down start clicking now the other thing that’s important not only should the light be dimmed in general but the room itself should be silent. We’ve talked about distracting thoughts. Well if there’s conversation going on in the same room or right next to you, that’s going to be distracting as well. Anything that distracts you from the reason you earlier there and your ability to maintain focus on that fixation point are going to impact the quality of the visual field. So, for example, in my office, the visual field analyzer, the automated perimeter, is actually located in the server room. So, we’ve got the humming of the server that acts as white noise and effectively blocks out telephone conversations things like that.

Additionally, we try as much as possible to schedule a visual field testing on days where that’s all we’re doing is testing. So, we don’t have a busy office full of patients and doctors and staff. And that tends to make it a much more pleasant, easier environment to maintain focus during the exam. Other offices will put the visual field into the back of the office away from the reception, and that’s also quite effective. In general, you don’t want the visual field testing to be done right in the midst of a busy, loud office. Right next to the reception desk, things like that.

Other things if you have a significant refractive error, so if you’re a moderate to high myopia, nearsighted, a hyperopia, which is what is term for farsighted or presbyopia, which is just basically anyone over 45, where you need correction or readers, right? Any significant refractive error really should be corrected. And there are little round lenses that can be put in front of your–of the eye that’s being tested. The other eye, by the way, should actually have a patch or shield or some kind of a *** it, because at least for glaucoma visual field testing you want to check one at a time other types of visual field testing you can check both eyes, it’s fine, but with glaucoma testing, it’s one eye at a time.

All right, so I’m going to park here for a bit because it’s a rather bumpy area of the road. Now, if you have a significant refractive error and the staff have not put something in front of your eye, then bring it up. Just inquire, “should I have corrective lenses?” Don’t assume that the office staff has been properly trained because some offices have a fair amount of turn turnover; I mean, I’ve worked with my nurse, Anna for almost 20 years. So, you know she knows my routine. I know hers, but not every office has staff that have been there for a long time and are well trained and experienced. So, if you’ve got a question, ask. The other thing that should be done is if this is your first time taking this particular test. Then the staff should provide some instructions for you. So what are you supposed to be doing, what are you looking for, where are you supposed to look, what do you do when you see something, how do you use the handheld controller what if you need to pause, how do you know when the test is completed. These things should be explained to you so that you’re not worried about these things during your test again. You don’t want to be distracted by anxiety, worry, concerns things like that.

Also, you should be comfortable or as comfortable as possible. There’s going to be a chin rest and a forehead rest you need to be up against that diving the chair or the table upon which the automated perimeter should be adjustable for your relative comfort. And so, these are things that can also be done.

And then, as far as what the physician will do once the visual field test is completed, either printout or an electric document will be sent to the physician who will then have a chance to review it. In general, the technician will not give you the results. They are trained to perform the test but not to read the test results. So, then the doctor will take some time to read the test, compare it to your prior testing, and then go over that with you most likely at your next appointment or later that day if you’ve done a test on the same day as your appointment.

So anyway, hopefully, this will give you some idea of how you can make the most of this testing that you’ll need to do. And anyway, we’re not done with this series of visual field topics. there are one or two more things that I still want to talk about, but this was a particularly important for anybody who’s actually performing the tests at this time all right see you next time

References:

1. Drance SM, Berry V, Hughes A. Studies in the reproducibility of visual field areas in normal and glaucomatous subjects. Can J Ophthalmol. 1966;1(1):14–23
2. Goldthwaite D, Lakowski R, Drance SM. A study of dark adaptation in ocular hypertensives. Can J Ophthalmol. 1976;11:55–60. http://europepmc.org/abstract/MED/1247940
3. Weinreb RN, Perlman JP. The effect of refractive correction on automated perimetric thresholds.
   Am J Ophthalmol. 1986;101(6):706–709

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2. Visual Field Testing – Appropriate Frequency | Driving with Dr. David Richardson – Series 2 Ep 03
3. Visual Field Testing – What It Is | Driving with Dr. David Richardson – Series 2 Ep 02
4. Visual Field Testing – Why We Do It | Driving with Dr. David Richardson – Series 2 Ep 01
5. Physical Activity and Rate of Visual Field Loss