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  • "Eye exercises will improve your vision."

  • Can I just do this, please?

  • Jennifer Tsai: Yes. [laughs]

  • "Contact lenses can get lost behind your eye."

  • Uh, no.

  • "If you sneeze with your eyes open, they'll pop out."

  • I don't know where to start with this.

  • Um, myth.

  • Hi, my name is Dr. Rani Banik.

  • I'm a board-certified ophthalmologist

  • and neuro-ophthalmologist.

  • And I'm Dr. Jennifer Tsai,

  • practicing optometrist in New York City.

  • I specialize in medical and aesthetic eyecare.

  • And today, we will be debunking myths about vision.

  • "20/20 means you have perfect vision."

  • Ah, that's a good one.

  • A lot of people think 20/20 means perfect vision,

  • but there is so much to vision

  • beyond just reading the eye chart

  • and reading down to 20/20.

  • And when we say 20/20 vision, it means that this chart

  • is at 20 feet away from the patient

  • and they can read all the way down

  • to this line right here.

  • There are other lines below that.

  • Some people can actually read even better than 20/20.

  • But there are so many other components of vision.

  • For example, there's color vision,

  • there's peripheral vision, there's contrast.

  • Tsai: And we also check for near-point vision,

  • which has to do with reading up close.

  • And technically, you could have 20/20 vision

  • but have a condition such as glaucoma,

  • which can cause peripheral vision loss,

  • which means you have perfect 20/20 vision in the center

  • but you might have side vision loss.

  • "Blue light will damage my eyes."

  • Oh, my gosh.

  • I don't know what to think about that.

  • Back in 2018, there was a study that came out

  • that the media picked up on, and they said,

  • "Oh, blue light is going to damage your retina.

  • It's going to cause permanent blindness."

  • What the researchers did in this study was they took cells,

  • they put them in a petri dish,

  • and they exposed those cells

  • to high, high levels of blue light,

  • and they found out that those cells died.

  • The truth is that the cells that they put

  • in that petri dish were not even eye cells.

  • They were cervical cancer cells.

  • So, our retina cells have pigments

  • that protect us against blue light.

  • They're called lutein and zeaxanthin.

  • They're like our natural blue blockers,

  • and they protect our eyes against blue light.

  • So there is no proof that blue light damages your eyes.

  • And if it were really true,

  • we would actually have a pandemic of blindness

  • because all of us are on devices all the time,

  • children, adults, and it's just not true.

  • We do know that it affects our sleep

  • and it does cause insomnia

  • because it changes our circadian rhythm.

  • So when you wear a blue-light coating on your glasses,

  • it does help with light sensitivity and glare

  • and just generally making you feel more comfortable

  • when you're doing work.

  • So there is no downside to it.

  • The tint does make a difference,

  • because if you put on the lighter-tint blue blockers

  • and if you look at your screen,

  • if you can still see the color blue,

  • it means that that blue blocker's not blocking out

  • 100% of the blue light.

  • Maybe it's blocking out a certain lower percentage,

  • maybe 30% to 40%,

  • versus if you put on these,

  • these are the super-duper blue blockers.

  • If you look at a screen Tsai: I love those.

  • with these on,

  • you don't see any blue whatsoever.

  • So, for example, if I'm having trouble sleeping

  • and I need to use my computer at night,

  • I'll wear these at nighttime, two hours before bed,

  • so it doesn't really interfere with my sleep.

  • The other thing that can happen

  • when you're on a screen for a long time

  • is probably you're not blinking enough,

  • so you're probably also getting dry eye,

  • and that's probably also contributing to the eye strain.

  • "You will lose your vision as you age."

  • I hear this all the time from my patients.

  • I have patients who are older,

  • your 60s, 70s, 80s, even 90-year-old patients

  • who still have 20/20 vision.

  • Tsai: Sometimes the dinner menu gets harder to read

  • at the restaurant, and I tell them that's absolutely normal.

  • That's not losing your vision.

  • It's just that our vision starts to change

  • in the other direction sometimes.

  • So, when we're referring to presbyopia,

  • that is the gradual change

  • when our eyes are not able to accommodate or focus

  • on near objects as well,

  • and we tend to hold things further back.

  • Banik: So, why does this happen?

  • Well, it's because inside the eye, we have a lens.

  • Now, normally the lens is very flexible,

  • and it can change shape.

  • Sometimes it can get thicker or thinner in the middle.

  • That allows us to focus at different distances.

  • As we get older, though,

  • this lens just doesn't change shape as well.

  • It becomes more stiff.

  • And when it becomes more stiff,

  • that is called loss of accommodation, or presbyopia.

  • And, again, that usually happens to most people

  • sometime in their 40s or 50s.

  • We also notice that over time,

  • our eyes start to improve as we get older.

  • It has to do with the fact that as we grow,

  • our eyes elongate,

  • and that can lead to myopia, or nearsightedness,

  • and over time,

  • just like our body can shrink,

  • our eyes can shrink shorter,

  • and that can lead our prescription to go the opposite way.

  • There's lots that can go wrong,

  • but as long as you see your eye doctor regularly,

  • you get checked for it, you get it taken care of,

  • you can still maintain good 20/20 vision

  • into your golden years.

  • "LASIK means no glasses forever."

  • I wish that were true,

  • but there is no guarantee with any kind of procedure

  • that your vision will be what you hope it to be.

  • Tsai: LASIK is just resetting your prescription

  • back to zero.

  • So LASIK can provide sharp, clear vision,

  • but that doesn't mean it can prevent myopia regression

  • or the need for reading glasses.

  • Sometimes there can be regression,

  • which means that after six months or a year,

  • the cornea may start to change back into its natural shape.

  • For the most part, it is very, very safe,

  • but just make sure you talk to your surgeon about it first

  • to make sure that you're a good candidate,

  • because not everyone is a good candidate.

  • OK. "Color blindness equals seeing in black and white."

  • This is an interesting one.

  • A lot of people think that if you have color blindness,

  • that's all you're going to see, is, like, monochrome,

  • but it's not true.

  • Most people who have color blindness,

  • or what we call color deficiency,

  • have issues with seeing different shades

  • of reds and greens and sometimes also oranges and yellows.

  • It's not that they can't see those colors,

  • they just see those colors differently.

  • So, we have cells in our retinas called photoreceptors.

  • The rods are responsible for light and dark vision.

  • The cones are responsible for color vision.

  • So we have red cones, green cones, and blue cones,

  • and these cones are all tuned in to certain wavelengths.

  • So in people who are color-blind,

  • it's not that they don't have those cones.

  • It's just that those cones are set

  • to a different wavelength.

  • So instead of seeing a red as bright red,

  • they may see it kind of as a muted color

  • or maybe as, like, an orange or yellow.

  • Actually, it's pretty common in the population

  • to have color blindness.

  • I think it's, like, 8% of the population.

  • If you go to the eye doctor,

  • they can do a color test on you.

  • It shows you numbers within patterns of color,

  • and it tests the intensity, or density,

  • of how much color blindness there is over a spectrum.

  • But it really doesn't impact someone's life at all.

  • People with color blindness function completely normally,

  • and there is no long-term issue with that.

  • "Eye exercises will improve your vision."

  • What do you think about that?

  • This is a myth. Can I just do this, please?

  • Tsai: Yes. [laughs]

  • Forget about it.

  • So, there is just so much misinformation out there

  • when it comes to eye exercises.

  • Many people think that if they do certain exercises,

  • that will help them decrease their myopia

  • or their hyperopia or their astigmatism.

  • I wish that were true, but there is no truth to that.

  • Our eyes are shaped in a certain way,

  • our corneas are shaped a certain way,

  • the length of the eye is a certain way,

  • and what you do in terms of exercises will not change that.

  • So it is probably one of the biggest myths out there.

  • You may have heard of the 20/20/20 rule,

  • which is every 20 minutes, take a 20-second break

  • to look at something 20 feet away.

  • And really, the whole goal of that is just

  • to allow your eyes to relax off into the distance.

  • So that does help relieve a little of that strain,

  • but it certainly isn't something

  • that corrects for your vision.

  • There is one condition where eye exercises can help.

  • It's a condition called convergence insufficiency,

  • where if we're looking at something up close

  • for a long time, the eyes get fatigued.

  • They start to drift out a little bit.

  • So, there is one exercise called pencil push-ups

  • where people can help strengthen those muscles

  • and help them focus longer and not feel that fatigue.

  • Maybe it'll prevent them from seeing double,

  • but it won't actually change the power

  • or the refraction of the eye.

  • So I think the best way to improve your vision

  • is simply to go to the eye doctor,

  • find out what the issue is, and get it taken care of.

  • "Wearing glasses will make your vision worse."

  • I get this all the time from my patients.

  • Like, "Doctor, really, do I need to wear these glasses?

  • Isn't it going to make things worse?"

  • The truth is, no.

  • What happens is, when people are seeing blurry,

  • they wear their glasses and then they see clearly,

  • but then they take their glasses off.

  • All of a sudden they're seeing blurry again.

  • Wearing them or not wearing them

  • does not cause progression.

  • The change has more to do with genetics

  • and just natural axial elongation of your eyeball.

  • So, an analogy I like to use with my patients

  • is, let's say you hurt your ankle

  • and you can't walk properly, so you use a crutch.

  • It's going to help you,

  • but it's not actually going to worsen your ankle.

  • So if your eye doctor thinks you need glasses

  • or contacts and prescribes them for you,

  • it's for your benefit.

  • It will help you see better, so please wear them.

  • "Dry eyes aren't very serious."

  • That's a tricky one. Most of the time,

  • dry eyes might not be serious,

  • but it could cause potential issues

  • that lead to scarring on the cornea.

  • I would say 80% of the population

  • might deal with some sort of dryness.

  • In fact, children are experiencing it at a much younger age.

  • We're noticing that, statistically speaking,

  • about 125 million people

  • ages 18 to 50 experience dryness,

  • but they don't report it or do anything for it.

  • So, if you can imagine,

  • when we are looking at our phones or reading a book,

  • we tend to just stare,

  • and that means our blink rate decreases by at least a half.

  • So we lose our blink completeness,

  • and over time, our tears can evaporate much, much quicker.

  • But when you go see your eye doctor,

  • usually they'll use different dyes or colored strips

  • that can help to stain the cornea

  • to see exactly how much dryness you have

  • and where the dryness is.

  • And there are actually ways to also image the glands.

  • The truth is, you really need to use the drops very often.

  • It's not just once a day.

  • You need to use them multiple times during the day.

  • Dry eye's like dry skin, so lubricate frequently.

  • It's OK to get generic

  • as long as you look at the ingredients

  • and there's no ingredient called polyvinyl alcohol.

  • If you see anything with alcohol in there,

  • please don't buy it,

  • because that can actually irritate your eyes even more.

  • It's not fully pH balanced to your eye.

  • It could actually make things worse.

  • In most cases, dry eyes are not serious,

  • but sometimes they can be,

  • so don't let it get to that level

  • where it becomes serious.

  • "If you sneeze with your eyes open, they'll pop out."

  • I'll let you take that one.

  • I don't know where to start with this.

  • Myth.

  • There's a certain condition that can cause proptosis,

  • which is the bulging of the eyes, though it's rare.

  • It just has to do with the elasticity of the lid itself.

  • If you have more relaxed lids, and the eyes,

  • when you sneeze, it can pop out a bit.

  • But certainly, they don't fall out.

  • You don't have to search for them on the floor

  • or anything like that.

  • We actually have, in our eye socket,

  • it's a really intricate network of muscles

  • and connective tissue that keep the eye in its place.

  • So, you can see that there's one, two, three,

  • there are some on the bottom, four,

  • and then there's two others in the back.

  • So there are six eye muscles behind each eye.

  • These eye muscles are connected

  • to the back of the eye socket.

  • They hold everything in place.

  • So there is no way

  • that the eye could actually come out of the eye socket.

  • It's a good thing.

  • Our eyes actually automatically close when we sneeze

  • as a natural reflex,

  • and it has to do with our body's way

  • to really expel what it thinks is an issue or bacteria.

  • So it's probably impossible to sneeze with your eyes open,

  • so just let your body do its thing.

  • "Contact lenses can get lost behind your eye."

  • Uh, no.

  • Definitely a myth, because you have

  • a protective barrier called the conjunctiva.

  • It's to prevent things

  • from getting dislodged back there.

  • I've had a patient who came in

  • and she kept thinking that the contact lens got lost

  • or it fell out.

  • And when she came in the third or fourth time,

  • I saw that she had four contact lenses on her cornea,

  • and that's because she thought it fell out.

  • But it was still on there,

  • but she just kept putting in a fresh pair

  • every single time. All you really have to do is

  • just make sure you blink a few times,

  • put in some artificial tears

  • to get that contact lens to loosen up,

  • and, eventually, it should come out

  • and you should be able to find it

  • and pull it out of the eye.

  • Most of the time, I notice that patients just actually

  • rub their eyes and the contact lens falls out,

  • and they think that it's still back in the eye.

  • And when I check, it's not there.

  • That's happened to me.

  • Tsai: Yeah.

  • "Sunglasses aren't necessary."

  • Myth. Total myth.

  • You do need sunglasses,

  • because we always want to protect our retina

  • and our macula, our lens, and our cornea.

  • So, these are mine.

  • Do you have yours?

  • Banik: I do. I have mine.

  • Go ahead and put them on.

  • Honestly, they make you look fashionable and cool

  • while protecting your eyes at the same time.

  • We are constantly exposed to sunlight exposure,

  • even on cloudy days. And when that happens,

  • even though the progression might be slow,

  • it can put our eyes at risk in the future

  • for other issues or long-term consequences.

  • The UVA and UVB rays are so powerful,

  • they can burn your cornea, they can burn your retina,

  • they can lead to growths on the surface of the eye.

  • They can even lead to eye cancers or eyelid cancers.

  • Here are some tips for sunglasses.

  • All sunglasses are not made the same.

  • Darker does not always mean better,

  • so you want to make sure the label says

  • "100% UVA, UVB protection,"

  • or it might say, "Absorption up to 400 nanometers."

  • You also want to make sure

  • that you go for oversized or even one that wraps around,

  • because you actually are constantly exposed to sunlight

  • from top and from the sides.

  • Things like polarized lens doesn't always equal

  • more UV protection.

  • Same thing like mirror lenses or tinted lenses.

  • Banik: Yeah, they can definitely help.

  • They can cut the glare,

  • especially if you're skiing or out in the water,

  • snowboarding, et cetera,

  • but you want to get the UV protection

  • in addition to the polarization or the tint.

  • "Floaters are always harmless."

  • Floaters are actually very, very common,

  • but they're not always harmless.

  • There are a lot of different structures inside the eye,

  • but this structure here, it's clear plastic,

  • but inside the eye, it's actually a jelly

  • called the vitreous that helps to keep the shape of the eye

  • so it doesn't just collapse.

  • But this jelly is made out of lots of different things,

  • water and collagen and hyaluronic acid.

  • As we get older, the jelly,

  • instead of being firm like Jell-O,

  • starts to break down.

  • And when it breaks down into more of a liquid form,

  • we start to see little pieces of collagen

  • floating around inside of it,

  • and these little pieces of collagen,

  • when light comes in through the front of the eye,

  • it hits those little collagen strands

  • and creates a shadow on the retina,

  • and that's what we see as a floater.

  • Tsai: I think it's estimated

  • that about 80% of people have floaters.

  • In most cases, they're benign,

  • but sometimes they can be associated

  • with more serious eye conditions.

  • If you have a shower of new floaters,

  • it may be an indicator that you're developing

  • a retinal tear or retinal detachment,

  • which is really an emergency.

  • You really need to get that checked out right away.

  • Or sometimes people have floaters

  • because they have inflammation inside the eye,

  • and that usually is associated with blurred vision,

  • flashes of light, sometimes pain or redness.

  • Definitely get it checked out if they're new

  • if you've never had floaters before.

  • "Two blue-eyed parents can't have a brown-eyed kid."

  • That's a great one. Genetics is a complicated topic,

  • and even though you think that blue eyes are recessive

  • and if you have two blue-eyed parents

  • they're guaranteed to have a blue-eyed child,

  • it's not always the case.

  • There's a particular gene called OCA2.

  • It helps determine if someone's eye color's

  • going to be brown or blue, but there are different ways

  • the gene expresses itself.

  • So sometimes the gene is truly dominant,

  • but sometimes only partially dominant.

  • So, there's a lot that goes into

  • determining a baby's eye color,

  • but definitely it is possible, not common,

  • but it is possible for two blue-eyed parents

  • to have a brown-eyed child.

  • And also, babies, when they're born,

  • they tend to have lighter eye color.

  • And then usually over the first couple of years of life,

  • usually by the age of 2,

  • that color may darken to its ultimate final colors.

  • The pigment migrates into the iris.

  • Sometimes it takes a while

  • for that pigment to fully migrate

  • and then fully kind of settle.

  • You use your eyes when you first wake up

  • to when you go to sleep, so you want to protect it

  • by making sure you wear sunglasses,

  • keep your eyes lubricated, and to wear your correction.

  • And so definitely start early, you know,

  • eat healthy, exercise, see your eye doctor.

  • If you do all these things,

  • you can hopefully maintain healthy vision for a lifetime.

  • You want to be proactive about it

  • and prevent it from happening.

"Eye exercises will improve your vision."

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Eye Doctors Debunk 13 More Vision Myths | Debunked

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    林宜悉 發佈於 2022 年 05 月 02 日
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