Introduction to Refractive Errors

There's three main refractive errors, and you've probably heard of them before, and now you're going to get a chance to really sit with it in detail. So they are medically known as myopia, hyperopia, and astigmatism.

The colloquial way of saying it, myopia is the same thing as nearsightedness. Hyperopia is the same thing as farsightedness, and astigmatism, that's astigmatism.

This is Doctor Talks, real talk from real doctors on the issues that matter to you most. I'm your host, Dr. Rani Banik, and today I'm so honored to have our expert guest with us, Dr.

Damaris Raymondi. Thank you so much for having me. I'm so excited to cover everything we're gonna go through today. Absolutely, and just for our audience, Dr.

Raimondi is an optometrist. She's based in New York City. She is well recognized as a leader in her field, and I'm so privileged to know her as a colleague as well as a friend.

Again, we're so glad to have you with us today. So I always like to begin by asking my guests, Dr. Raimondi, what was it about optometry that interested you so much that you decided to pursue this as your career?

That's such a common question that I get all the time and it goes all the way back to the story of me needing my very own first pair of glasses, it was in the seventh grade and I started taking Italian class.

And my last name is Raymondi, last name R. So I was not sitting in the front of the classroom, but all the way in the back. And I grew up speaking Spanish at home.

And the interesting thing about Spanish grammar is that it's totally different than Italian grammar. So learning Italian as a foreign language as a seventh grader was challenging.

And I started getting low grades. And I didn't understand that the other kids next to me were seeing things clearly.

Dr. Raimondiu2019s Path to Optometry

I brought it up to my parents and somehow they were like, we gotta get you over and get your eyes examined, get your eyes tested. I got my first pair of glasses and like most people with their first experience with glasses, they look outside, they see a tree and they see every single leaf and they're like, oh my God, you're supposed to see every detail.

That's exactly how I felt and I loved it. for a month as any seventh grader, only for a month because after that I couldn't stand the feeling of glasses on my face.

This was around the time when AccuView was putting out flashy commercials on MTV and they had you go on their website, print out a coupon to try out your first trial pair of AccuView contacts.

I dutifully went and printed it out and told my parents, I want to wear contacts. And they were like, OK, let's go for it. And they took me. The optometrist was awesome enough to try them on with me.

He was the only middle schooler with contacts. I would tell everybody about it. I thought it was the coolest thing. Like, glasses were cool. Contacts were even cooler.

And just the fact that I could see clearly from then on, I knew, I mean, everybody needs to see this clearly. And slowly but surely an interest arose from that.

And that's how I ended up in optometry. I'm so glad you pursued your dream because you've helped countless patients with their eyesight. And I just want to go back to what you were saying earlier about not realizing that there's so much of the world people you may be missing if you have the need for glasses or contacts and you don't know that you need them.

It's really truly pun intended eye opening when patients get their first prescription and all of a sudden they can see so many details. They see details of the world around them.

They also see details looking at their own face in the mirror. People say, oh my goodness, I didn't know I had so many lines on my face or wrinkles, but now I can see them so clearly.

But regardless, it's always best to optimize your vision or visual potential by wearing the right prescription. And Dr. Ramadi, if you could just describe for us, what is refractive error?

What are the components of refractive error? Which is basically the metric we use when we talk about someone's prescription. Yeah, so a refractive error is basically the power that goes in a person's glasses or contact lenses or intraocular lens.

But refractive error is the formula, the prescription, like you said. And what it is, it tells us about where the light ends up focusing within your eyeball, how far away it is from the retina.

Is it right on it? If light focuses perfectly onto the back of your eye, onto your retina, you have no refractive error. You have no prescription, and that's known as emetropic.

And then there are other forms of refractive errors that we will get into, but that's what it is. It tells us where light ends up focusing within our eye.

For our audience, could you just explain a little bit about the optics of the eye? What are the components that play into determining whether light, the light can focus perfectly onto the retina or not?

There's many different components. Optics is such a, that's another, going back to your first question in physics in undergrad, when we got to the optics chapter of physics, I just found that so fascinating that, oh, this is where the glasses prescription comes from, from where the light ends up hitting your eye.

So there's lots of different components that we need to see clearly. And I explained this to every single patient who's in my chair. We could start off with the tear film.

The tear film itself, it's made out of water, mucin, oil, and it has all these different sub-components. All three of those, three layers, three layers within the tear film itself.

How the Eye Focuses Light

That's on the topmost part of your eye. They all need to be in perfect harmony for you to see clearly. But what else needs to be in perfect harmony? Your cornea, that's right underneath your tear film.

And that actually has a really large Refracting power our eyes, it bends light so that it does hit your back of your eye and your cornea so your tearful is going to be perfect your cornea is going to be perfect for you to see clearly perfect and healthy.

and there could be many corneal diseases. The next thing that needs to be really good is, well, your anterior chamber needs to be clear, although that's not really a refracting power, but I'm thinking about all the things.

The next big component of your eye that is used to bend light is your crystalline lens. And it's just like the name, it's a little lens. I like to describe it to patients like a clear little M&M sitting in the middle of your eyeball.

also bends light to a large degree. So that needs to be clear, beautiful, and healthy. And able to focus at different distances. Dr. Raymondi, like the lens is able, is dynamic, is a dynamic structure.

And if you could explain a little bit more about how that works when we're looking at something far away or up close, how the lens changes shape. Sure, the lens definitely changes shape.

When we are looking at something really far away, our lens becomes nice and skinny and very relaxed. And when we are looking at something nice and up close, it gets really nice and thick and fat.

And it changes just like a camera. When we look far, our eyes are most relaxed. When we're looking up close, that crystalline lens thickens and it all changes.

Okay, so with all of these various different components working together, how likely is it that the light stimulus or the light rays coming into our eye will actually fall perfectly on the retina?

It's pretty, actually most people, it seems to me most people would have some errors either in the cornea or in the lens that would cause them to have some degree of refractive error.

What have you seen in your practice? Like what percentage of your patients have some kind of refractive error? It's really interesting that you say this, Dr.

Banik. I've been doing this now for, I'm approaching 10 years in an official capacity of seeing patients. I guess the majority of patients do have a refractive error, but I'm based in New York.

I get patients from all over the world. And jumping ahead into some details, I see a large generational difference. from patients who grew up and in a different country, grew up in the outdoors.

And that could be anywhere outdoors, could be South America outdoors, could be Asia outdoors. A lot of these older patients, their distance vision, the smallest, tiniest refractive error that you can find, many times I end up finding zero or perfect distance vision.

But then when we're going to younger generations who grew up mainly here in New York, I find all different ranges of refractive errors. So it's definitely population-based.

I would say nature versus nurture, a large part nurture, depending on what your childhood experience was like. I'm so glad you brought that up, that there are differences, there are genetic differences, but then there's also lifestyle differences.

And you mentioned how much time people spend outdoors, how much time do they spend up close where their lens has to focus so much and put in so much effort to focus up close.

First, let's talk a little bit about the three main types of refractive errors there are, and what does each of them mean? So I'll let you explain what those three are.

There's perfect, which we were going into in a way where there's no prescription, but there's three main refractive errors. And you've probably heard of them before, and now you're going to get a chance to really sit with it in detail.

So they are medically known as myopia, hyperopia, and astigmatism. The colloquial way of saying it, myopia is the same thing as nearsightedness. Hyperopia is the same thing as farsightedness, and astigmatism, that's astigmatism.

So let's go into myopia. Myopia is hot, it's on everyone's radar. What myopia basically means, and I have my trusty little model right here, is that the rays of light end up focusing in not the most ideal part of the eyeball.

They focus in front of the retina. And why do they focus in front of the retina?

Myopia and Hyperopia Explained

Because in myopia, In the majority of cases, of course, with anything scientific, there's nitty gritty details, but overall overarching myopia means that your eyeball is longer than average.

So if it's longer than average in a perfect eye, the light is falling right here perfectly in the back and center of your retina. But if your eyeballs longer, where's the light go?

Where do you think it's going to focus? It's going to focus in front and going back to the crystalline lens, as that shifts focus and changes, it never ends up, you see where my finger's going?

It never ends up on the retina. It stays in front, no matter how hard you squeeze, how hard you focus. So for myopia, typically you need a pair of glasses, contact something to get the light rays to focus on the back of the eye.

So basically, to shift the light image back onto the red. It's a specific type of lens. It has a certain shape that will refocus that image. Again, the optics play into this very much, and it allows people to see.

So fascinating, Dr. Ramandi. What's the next type of refractive error that you commonly see in your practice? So that was nearsightedness. The next type is hyperopia or farsightedness.

So what this means is that the eyeball is a little shorter than average. And where did the light rays fall in a hyperopic eye or farsighted eye? They fall back here.

So what that means is if you do crank up the focus, you can reach this part in the back of the eye to reach clarity and clear vision. And hyperopia, while it means farsightedness, what I find is that in large amounts, it can impact both things up close, the clarity of things up close and the things far away.

Hyperopia, if a patient has no prescription, usually they do have a little bit of hyperopia. And it's super common. And a lot of times, hidden hyperopia is revealed after the age of 40. So that would be hyperopia.

The light rays are focused all the way back here. Could you just explain a little bit more? What do you mean about hidden hyperopia? Because I've had so many patients come to me.

They've never worn glasses their whole life. They always say, oh, I saw perfectly. I saw 2020 or better than 2020. Sometimes patients can see 2015 on the chart.

But then they hit their 40s or maybe even earlier and all of a sudden they can't focus and they end up needing glasses. So is this what you mean by hidden hyperopia?

Is this kind of an example of why people may have this sudden need for glasses once they reach mid adulthood? Partially, definitely. So what ends up happening is with myopia, if you recall, the light rays are focused in front of the eye.

And no matter how hard you strain or how hard you try, those light rays, since they're in front, they're never gonna hit the retina. Now going back to hyperopia, you can have a power or a need, right?

And it's focused in the back of the eye. If you strain or focus hard enough, you can make those light rays reach the back of the eye. When we're younger than 40, when we're in our 20s and our 30s, that focusing is super easy to get it back here.

Our crystalline lens, the one that gets skinny and then really thick that changes shape, it's pliable. It's able to crank in that focusing without you noticing.

But what I often explain this to patients as, it's like holding a weight in your arms. You hold a weight in your arms. And in the beginning, it's okay.

Let's pretend that you wake up in the morning and you hold some five pound dumbbells in your hand. In the morning, you're okay. Afternoon, gonna get fatigued, by the end of the day, you're done.

And you can compare that to years, 30, 35, 40, 45. You can still crank some in, but as soon as that crystalline lens hardens, you're no longer able to clear that small prescription.

And technically, that hidden hyperopia, that hidden prescription was always present. But just like many things change once we're a little older, our eyesight changes a little too.

Yes. That would be one part of it. Yes. Thank you for explaining that. And I love that analogy of having to hold weight, like your muscles are just working all the time.

You may not realize it initially because it's a small amount of weight, but over time it can really build up and really fatigue you. So a lot of people will have fatigue, visual fatigue when they have this hidden hyperopia or latent hyperopia.

that they've been struggling with for most of their life. This has been such an amazing, fascinating discussion, Dr. Ramandi. I am so interested to learn about the third type of refractive error, which you mentioned earlier, astigmatism.

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Fortify, empowering your vision. So Dr. Ramadi, tell us about astigmatism. What is it and how does it impact our vision? I want to start off with saying that I see a stigmatism every day in practice.

A lot of people have a stigmatism and it depends to what degree you have it. But what even is this word confounds all the patients, some people who say they have it, some people who don't have it think they have it, all these things.

What does it mean? So we went over myopia where the light focuses in front of the retina. We went over hyperopia where the light focuses in the back of the retina.

Astigmatism means you have more than one focal point. You have two and you have two and they might be two that are separated in the front or two that are separated in the back.

And there's a whole circle of least confusion optics that goes into it. But the other way that I like explaining it very simply to patients is that along one axis of your eye you need extra power and that axis when you trace it back to optics let's say it's this line like a let's imagine a diagonal slash a slash right here you trace it back here and it'll show up as two different focal points So you're saying like a cross, that's what you're saying, like something like this.

So if you're going to focus, like if you're looking at a cross, you're focusing this at a certain place and you're focusing this at a different place.

Is that safe to say, Dr. Ramadi? Yes, correct. And when it's focused in different places, before we were just talking about a point of light, when they're focused in different places, things are distorted, those can appear wavy or crooked, or when patients notice it is when they're driving at night and all the light is bended.

So when we correct astigmatism, we end up collapsing this cross and making it into one point when you wear glasses. Got it. So it can be corrected with glasses.

Now, where does astigmatism come from? You said that, you mentioned earlier, there's so many components to refractive error. Where do you see most of your patients that the astigmatism is derived from?

I see most of it as corneal astigmatism. So that's probably where a lot of patients have heard that their eye is football shaped. Football shape is more so like a math term or a math graph.

If I were to map it out, Mathematically or graphically, it would come up as a football. But on the cornea, what it would look like actually, oh, I have a handy cornea right here.

Look at that. So do you see this perfect little dome? This would be an eye without astigmatism. An eye with astigmatism would have forward facing, it would look like a number, a large number eight or like a bow tie.

But if we look at it like this, remember I was talking about the perfect dome. If you think about this dome and no astigmatism, it'll focus to a point.

With astigmatism, this is not a dome. Instead, you have two hilltops. And when you have two hilltops, you're going to have two different points of focus.

So in majority of cases, corneal astigmatism. There are details, of course, but this is most patients. It's all in the cornea right here. It's not perfect.

It's a little, sometimes in some patients you have to focus, say that it is a little tiny bit deformed. So oftentimes I've heard of astigmatism being described as either a football or more of an elliptical shape, but it's not something that patients could just look into the mirror and see themselves, right?

It's not that you hear you have astigmatism and then you go looking to see if your eye is perfectly round. It's not something patients themselves can discern.

Astigmatism and How Itu2019s Corrected

Yes, correct. And that's why I shy away from that. I don't mention it as football shaped because it's not that it's more about where the points are sitting and the way that people understand it with glasses.

If you look at one angle, that angle has a different prescription as opposed to the rest of the surface of that lens for your glasses. And I loved how you gave the analogy of the figure eight and the two domes, like there's a little hilltop and then a trough and then another little hilltop.

Wow, that was so helpful. Dr. Ramadi, I've had so many patients when they hear the word astigmatism, they get so frightened. They think it's something really bad.

They think it's something that will… Your stigmata. Yes, exactly. It sounds so scary, but in reality, it's very common. And I can just tell you, for a long time, I believed that I was just myopic, meaning I had myopia and nearsightedness.

And for many years, my prescription was corrected just for myopia. And then once about, I think it was about eight, nine years ago, I went to my eye doctor and they said, oh, you have some astigmatism in your right eye.

And I said, no, that can't be. I don't have astigmatism. I have only myopia. And this is, you know, you have a little bit of astigmatism. And the truth was I had it all along and no one ever corrected it for me.

But when it was corrected for me, I realized that a lot of the glare and the halos I was seeing, particularly at night, that all went away. So I know people can be afraid of the term, but I just want to reassure people that it's very common and there are wonderful ways to correct for it, correct?

Absolutely. There's many ways to correct for it. And this also, if I can give like another side to this story to it, it highlights the importance of getting your eyes examined thoroughly and every year as well.

Because on the flip side, a lot of times astigmatism, even though it's to me, it's a refractive error, it's something that can be corrected with glasses or contact lenses.

It can be caused from a person over-exerting their eyes. There can be a sort of fake astigmatism, as you could say. There can be some astigmatism that shows up because remember how I said the cornea is not perfect and there's the two domes and that trough?

Sometimes that could be brought upon because of dry eye or other ocular surface diseases. So it's not really the astigmatism, but it's the tear film and the cornea that are suffering.

And once you fix that, you fix the astigmatism. So there's so many things that go into it. Get your eyes checked by an expert to know exactly where you're at.

Yeah. And as an eye doctor, what are some of the tools you use in your practice to help to identify or uncover whether someone has myopia or hyperopia or astigmatism or maybe a combination of all three?

One of my favorite tools is something that's been around for a long time, and those are dilating drops. You mentioned earlier, Dr. Banach, all the up close time we spend on screens, on books, all the demands that society makes of us today in all age ranges.

I often find that eyes are so tired and so overworked and over focused that I need to dilate my patients. What dilating does, it does two things for me.

Well, it opens up your pupils so that I can check the health inside of your eye and see what else is going on there. what it also does when it opens up your pupils it relaxes your focusing system which what we call the your accommodative system and when it relaxes that I'm able to see all the hidden prescriptions I'm able to see what's really going on with your eyes and I have uncovered so many different refractive errors and what a patient presents within all ages because of the near demand that computers and screens have on us.

In the past, I believe we would, when I graduated in 2015, we learned that mainly children are able to over-focus and over-compensate, so we've got to be really careful with them.

But I'm finding that all age ranges are very much affected and I have to be very careful with what I'm prescribing because that's a huge tool that allows me to see what's going on.

Yeah, I love the fact that you said your best, most useful tool is the dilation because it's not some fancy piece of equipment that we need, right? That's really not it.

It's about being thorough. It's about uncovering things that may explain why a patient may not be comfortable in their glasses prescription. or they're having a lot of glare and halos or starbursts in their vision, especially at night.

And just for our audience, what Dr. Raimondo is talking about are drops that we typically put in for dilation. And we call this whole process a cycloplegic refraction.

And cycloplegic basically means that the system is paralyzed. Typically, we used to use it only for kids, but now it's really important to get that done, even if you're an adult, because again, there could be refractive errors that are hidden that could be uncovered.

So thank you so much for sharing that really important piece of information. I wanted to ask you something, Dr. Ramandi. A lot of people believe rightly or wrongly that by wearing glasses, that if they become dependent on their glasses, that their vision will continue to worsen or significantly increase in their power.

So what's your response to that type of concern that patients may have? It really depends. There are so many different ways this could go. It depends on the patient's age.

If they're a child that's emerging in myopia and if they're showing signs of nearsightedness, I will say for sure in that case, myopia is something that snowballs out of control, that avalanches and glasses in a child underneath 18 years old who has myopia and there's many different criterias, it can make things worse and it can cause a quote unquote dependency.

In a more typical setting though, I know that I'm performing a very thorough exam. And apart from the dilation drops, I also review the patient's ocular surface.

Is there a dry eye that's contributing to the starburst or halos? Is there something else underneath? There might be a disease process happening that's causing this lack in clarity.

And when this happens, I tell a patient, okay, we got your best prescription here. If this is your first pair of glasses, and if it's a large prescription, usually I'll go into this, I'll say, don't be alarmed.

Testing, Dilation, and Prescription Choices

You might find that you're reaching for it more often than not. And that's when patients refer to it as becoming dependent. But in reality, I'm getting you to see how everyone else is seeing.

I'm making sure that we are optimizing your vision so you can see as clearly as you possibly can. Of course there are caveats and every single patient is so unique in what they're feeling or what they're seeing.

I have to know how they're, like we were going into, I'd have to know what their tear film is doing. I got to know what their cornea is doing. I need to know what the different layers of the retinal cells are doing.

Believe it or not, I check this in every, you and I, we check this in every single patient that comes into our door. and there's many things that go into it.

But if I were to have an overarching answer, I'd say when it's prescribed, don't be surprised that you're seeing clearer. The goal of glasses or contacts when they're indicated is to make you more efficient, to have you quickly look at things.

Vision is automatic. When you look at something, it should be automatic. And if it's not, allow us to uncover and see what is going on. Oh my goodness, there's so many points you made that I would love to talk more about.

We are nearing the end of our interview, but I did want to just mention one highlight. One thing that you said is as eye doctors, it is our responsibility to help our patients see to the best of their ability.

And if we know that by wearing a certain prescription, whether it's through glasses or contacts or through surgery in an IOL or refractive surgery, we can get our patients to 20, 20 vision or better.

If we know that we will do our best to try to. to enable that, to help our patients along so that they can reach their visual potential. That's really our goal.

And in doing so, yes, you may realize that, like you said, you're reaching for your glasses more because it's helping you see better. It's not that you're becoming dependent on the glasses.

It's that they are helping you function better and your brain is enjoying that clarity, right? And the brain wants to see well and take in the rest of the world.

So thank you for bringing up some of those points. And for other people, I wanted to also bring this up. Different people have different visual needs, right?

Some patients need to see 2020, some patients may not. So can you explain some situations, Dr. Ramadi, in which you may not give a patient the full prescription because maybe they don't really need it?

And I will say, though, I love to give my 100% to every single patient. And I have had a few where I have taken them off of glasses. So on that that other spectrum, right, pseudo myopia, fake myopia didn't touch into I had one patient who for one reason or another, every year was increased a little quarter before seeing me.

And I had to tell him, your eyes are actually plain old zero. And my duty as a doctor was to tell him, we have to take you off of glasses. But instead, we slowly decreased the prescription.

And after two years, we got him to zero. So I absolutely have situations where I take patients off of it. I know most patients wish they were the following, but one case where I do this is mono vision.

Some of us are very lucky where we're born with one eye to see far and one eye to see near. It's not all of us, but in those cases too, if they are functioning good and they have no complaints and they're seeing 2020 with both eyes far away and both eyes up close because one is for the other one, one is working for one, one's working the other way.

In that case, I don't give them glasses. Let me see what other situations, depending on what language the patient speaks or more specifically what language they read in.

Roman letters can be very small. The newspaper writing, the traditional English, Spanish, ABCD, right? It can be written in very tiny font. But other languages, if you see their font, there's no way they can print it that small.

And if a patient reads in that language, whether that's, so what comes to mind is Chinese characters or Arabic characters or even Russian characters, those characters when they're in newspapers, right, the Cyrillic, fonts, they're larger.

So that patient is not going to need to see your size eight New York Times font. So in those cases, I haven't prescribed the full prescription because it's not necessitating that large demand.

For example, if someone is a pilot or a police officer, they probably do need their 20-20 vision. But if someone has a different type of profession where they don't need to read very small font, they're not doing up close near work, and they're not looking way off in the distance, most of their world is intermediate distance, maybe they don't need to have that perfect 20-20 vision.

So that's another situation which is more of a career slash lifestyle needs situation in which I may not give the patient the full prescription. And they may not ask for it.

They may say, I'm okay, I can do everything I need to do. My vision's 2040. I'm very happy with that. And if they say something like that to me, then I'll say, okay, that's wonderful.

I'll see you next year and we'll reevaluate and see how you're doing. So it is really a discussion amongst the patient and the doctor about the patient's needs that's really important.

And sometimes patients are like, wait, what? And I'm like, no, I need to know. I'm asking your occupation because I need to know how you are using your eyes throughout the day so that I can help you out better.

Closing Thoughts and Contact Information

Exactly. Exactly. Dr. Armani, this has been such an enlightening conversation. You helped to clear up so many aspects of refractive errors that I'm sure many patients, many people out there have questions about.

So we thank you for your wonderful insights. If anyone wanted to reach out to you, perhaps use some of your resources, maybe follow you on social media or even become a patient, how could they find you Dr.

Ramlandi? They can find me 24 seven online. I'm on Instagram at New York iDoc. So that's New York spelled out N-E-W-Y-O-R-K E-Y-E-D-O-C. And that's the same handle on TikTok.

And if they want it to become a patient, head on over to my website, suricare.com, just like it's spelled S-U-R. E-Y-E-C-A-R-E dot com and click make an appointment and that's where I'll be happy to see you in my exam chair sometime soon.

Wonderful and we will share all of those links to Dr. Raimondi's resources and her website below underneath the interview. So thank you again Dr. Raimondi for spending this time with us we truly appreciate you and thank you all for tuning in and stay tuned for our next interview coming up very soon.

Thank you so much. Take care. Thank you for tuning into Doctor Talks. We hope today's episode has enlightened and inspired you on your path to optimal health.

Each day is a new opportunity to make choices that empower your wellbeing. For more insights and strategies, subscribe to our podcast and visit our website, www.doctortalks.com.

Stay connected, stay healthy, and join us next time on Doctor Talks. Real Talks from real doctors on the issues that matter to you most.

Damaris Raymondi, OD

Myopia to Astigmatism: The Real Reasons Your Vision Changes