Glaucoma Tests

Video Transcript

"Well, let's talk about what are the tests for glaucoma. But, before we do that, let's talk a little bit about a bigger subject, which is who, how we figure out who has glaucoma. So we, you know, we have this normal population base that goes and gets their eyes examined, so you'll go and see your eye doctor for your eye exam, and then during the course of that exam we may find, you'll have a finding that's not within the norm. And, then that puts you in this other category, that we call glaucoma suspects. And, so glaucoma suspects are individuals that have essentially a higher risk for glaucoma. And, so those people that are glaucoma suspects, have a series of more sophisticated tests ran on them, to make sure that they don't have the beginnings of glaucoma. And, so those are tests specific for glaucoma, and so some of those things include a measurement of the pressure in your eye, a look at the optic nerve in the back of your eye, to establish if it's healthy or being damaged, a measurement of your peripheral vision, called a visual field test, a measurement of how thick the front of your eye is, called the Pachymetry, a measurement of how open that drainage system is within your eye, and that test is called Gonioscopy. And, then another interesting test which involves using a laser that scans the back of your eye, and lets us know how thick the tissue is in the nerve in the back of the eye, and that's called a scanning laser Ophthalmoscopy. So, let's kind of quickly hit these and I'll show you kind of briefly how they work, so the first thing is the pressure measurement. There's a lot of different ways that doctors like to do this, the most accurate way of doing this measurement is to use a microscope, like the one we have behind us here to figure, to measure the pressure in the eye. Sometimes we'll use devices that look like a pen, that we use to touch the front surface of the eye, that gently measures what the pressure is within the eye. So, we'll use that instrument, and that's really paramount in the management of glaucoma. Checking the pressure becomes really common, and it's something that we do very regularly in people that we think might have glaucoma. That's the one thing that we can control with glaucoma, the pressure, and so having a really accurate pressure measurement, and checking it regular becomes really important. The next thing we're going to do is, we're going to do a test where we look in the back of the eye, and we can do that a variety of ways. We can use microscopes, we can use other lenses to look in the back of the eye, but generally speaking, what happens when we look in the back of the eye, is that we use a microscope and shine some light in through here, through the pupil, looking all the way back here, in the back of the eye. So, we'll look at the optic nerve, and so that's a specific test and that's called Ophthalmoscopy, and that involves looking through here, in the back of the eye. And, we're trying to determine here is how healthy the nerve is. Third test that we're going to do is called a visual field, and that's kind of a lengthy test, and boy, a lot of people have a hard time with that, because it's so darn boring, and that's a test that we use that involves the patient that, to look inside a device that kind of looks like a white dome, the inside of a white dome. And, they'll look inside this device, and they're given sort of a trigger button and the instruments' going to shine different spots of lights in different parts of their peripheral vision with different intensities and the patient essentially uses a device to punch in, that lets us know when they see these spots of light. And, the result of that is that test is going to give us a map of how well the patient sees in their peripheral, so that's called a visual field test. The next thing, those are probably the three most important things that are done very, very regularly in the management of a patients glaucoma. Another thing that we learned from a study that came out a few years ago that suggested that patients that have a, patients can have a risk of glaucoma based on how thick the cornea is, and so the cornea is this part of the eye that's out here in the front, and so there's a measurement, there's an instrument that we can use that helps measure how thick the cornea is, and that test is called a Pachymetry. And, the Pachymetry measurement, the measurement of how thick the front of the eye is here, the cornea, it's taken typically once in the lifetime of that patients care with that doctor. And, so that, the doctor that you see will probably take this at some point. That gives them kind of a guideline of how to treat the patients glaucoma. The other test that we'll, that the doctor will do periodically is this test called Gonioscopy. And, that may happen a few times in the care of your glaucoma throughout the patients life. And, we always do it in patients that are glaucoma suspects, to figure out what type of glaucoma they might have. And, in Gonioscopy what happens is that we'll use a specific type of lens that has a mirror on it, we'll hold it here on the front surface of the eye, and it helps us look down into this intricate drainage system within the eye to figure out if it's wide open, or closed, what the status is of that drainage system. Those are in essence, the most important more common tests for glaucoma. There's an interesting technology that's been developed over the last few years that is becoming more, and more important in glaucoma management, and that's called a scanning laser Ophthalmoscopy. And, these scanning lasers, essentially what they do in broad strokes is the laser is used to shoot through the pupil, into the back of the eye, and it scans the optic nerve here. And, so what it's helping us determine is what, how thick the nerve is and there's a relationship between how thick the nerve is, and the likelihood of developing glaucoma. So, what scientists have learned in the last many years is that people that have glaucoma, tend to have these thinner, larger nerves over time, and that sometimes precedes the patients vision loss. So, those are some of the more common tests that are used in patients management of glaucoma and determine who has glaucoma."