WEBVTT
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Hello, my name is Parl Kator MD.
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I'm an ophthalmologist in Atlanta, Georgia, specializing in cataract and glaucoma surgeries.
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After practicing medicine for over a decade, I have learned that the more a patient knows about their disease, the better they do.
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Patient education is a passion of mine.
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But like most doctors, I have a lot of patients and not a lot of time to see them.
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So I created this podcast where I could spend the time I don't have during the day to give you insights into the eyeball and ocular disease.
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Let's empower you as a patient or a patient support system.
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Together, let's demystify the eye.
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Punny Halloween costumes are the bee's knee.
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One of the best Halloween costumes I have ever seen was one of these types of costumes.
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One of my residents had a tiny orange parking cone on her head, secured with a little rubber band strap.
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She was dressed in all black and was holding a carrot.
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No one at our work party, not a single person got it.
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She pointed to her carrot, then her hat, and said, Carrot a conus.
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Keratonus.
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A terrible disease.
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A brilliant costume.
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Statistics.
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Keratoconus comes from two Greek words, keras meaning cornea, and conus meaning cone.
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Together, these words perfectly describe this disease, which is a cone-shaped cornea.
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So is keratoconus worth talking about?
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How many people even have this disease worldwide?
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Well, over 23 million people.
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So yes, keratoconus is certainly worth talking and learning about.
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The statistic that always gets me is the age at diagnosis.
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This disease affects young people with an average age of diagnosis when a person is in their teens or early 20s, 16 to 25 years old to be exact.
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This is the time when our young people are just getting ready to embark on their life journeys, and this diagnosis changes the course of those lives.
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We do not believe keratoconus prefers men or prefers women, but there has been a particularly high prevalence in black females.
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This makes sense when you consider Africa as one of the highest populations of keratoconus.
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An updated review of keratoconus was published in 2022 and it showed Africa, India, and the Middle East as hotspots for this disease.
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Europe and North America had low prevalence rates, with Denmark having one of the lowest.
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Keratoconus is bilateral, which means it affects both eyes.
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It is often asymmetric, with one eye being affected more than the other.
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We know family history is a strong risk factor.
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Depending on the study you look at, if you have a first degree relative with keratoconus, you have a six to twenty five greater chance of having the disease yourself.
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25 times.
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That is huge.
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Pathophysiology.
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We had a professor there who specialized in neuroophthalmology.
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This is the connection between the optic nerve in the very back of the eye to the brain.
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We would ask her what she thought about cornea specialists.
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They specialize in the clear front portion of the eye.
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She was famous for retorting, how would I know?
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I'm not a window dresser.
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It was funny at the time, but mostly because the cornea is the window to the eye.
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It is the crystal clear dome at the very front portion of the eye that light hits first upon entering the eye.
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It is one of the two powerhouse refractors of the eye.
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This means it is one of the two structures that takes those parallel beams of light and makes them converge into one fine point on the retina in the back of the eye, allowing us to have the sharp vision we so desire.
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As the window of the eye, it is a hugely important structure, and doctors who specialize in it are not to be dismissed.
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When this structure goes awry, it can be in the form of cloudiness, such as with a corneal scar, or fuchendothelial dystrophy, another podcast episode in this season.
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If it remains crystal clear but loses its shape, diseases like keratoconus emerge.
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So what shape is a cornea supposed to be?
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It's supposed to be a sphere.
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Think of the epicot center.
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A beautiful, perfect sphere will make it so you don't need any glasses growing up.
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If the sphere is a little too steep, you are nearsighted.
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And if the sphere is a little too flat, you are far-sighted.
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If the sphere looks more like a football cut in half than a basketball cut in half, you have astigmatism.
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These are called refractive errors, and they can be fixed pretty easily.
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Listen to my podcast on refractive errors for more information about this.
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But what if this beautiful Epcot basketball disco ball sphere begins to bulge outwards?
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Imagine, if you will, a bunch of workers on the inside of a round cornea, putting their hands up to it and pushing with all their might.
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If the cornea bulges forward, it looks more like a cone than a sphere.
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When the cornea bulges, it gets thinner and steeper.
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Once light hits this cone, it gets bent into all sorts of wonky angles that have no chance of converging together into a fine point on the retina in the back of the eye.
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Light gets scattered everywhere.
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And this is kerataconus.
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One final important detail about the cornea is its layers.
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My sister is from Florida, and as I've noticed with most Floridians, she has become completely intolerant to the cold.
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I'm talking to the point she packs her ski outfit when visiting me in Atlanta if the weather is under 50 degrees.
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We recently went for a hike in Austin during a winter freeze.
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The temperature was 38 degrees, but with a wind factor, it felt like 27 degrees.
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I got to witness my sister preparing for said hike with one of the most fascinating displays of layering I have ever seen.
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I meanwhile had on sweatpants, a long-sleeve shirt, and a jacket.
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Forty-five minutes after she began dressing, we left the hotel room only for her to exclaim, Wow, it's colder than I expected.
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Better add another layer and run back in.
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The cornea's layers do what my sister was trying to do, protect herself from the elements.
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The cornea has six layers, and we will be focusing today on the middle layer or stroma of the cornea.
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This layer makes up the majority of the cornea.
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It accounts for about 80 to 85% of its thickness.
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It has parallel lines of collagen, peppered with keratocytes.
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Those are really beautiful star-shaped cells that maintain and support the stroma.
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The parallel lines in the cornea are important to remember for this podcast.
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To picture them, think about going to your neighborhood construction store and seeing those giant bundles of stacked plywood.
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Like plywood, the stroma of the cornea gives it its strength.
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But unlike plywood, the stroma of the cornea is crystal clear.
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No one knows exactly what causes keraticon.
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Does that sound frustrating to you, especially if you have it or know someone who does?
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Trust me, it's frustrating for your doctor too.
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We doctors admire the human body for the mysteries it contains, but we also hate a mystery we cannot solve.
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We do think there is a genetic component.
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Why?
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Because one in ten people with keratoconus has a parent with it, and that's just too high of a ratio to be due to chance.
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Additionally, scientists are now discovering a number of genes thought to contribute to the development of this disease and are still discovering more.
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But we also know that environmental factors play a role.
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What can people do or be exposed to that could create this?
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Well, we know of several.
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The first is eye rubbing.
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Oh my god, you're thinking, I rub my eyes like every morning when I wake up.
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Could I be creating keratoconus for myself?
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No, no, I'm not talking about general, your eye is itchy, so you rub it, or you just woke up and want to get the crust out of your eyes eye rubbing.
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I'm talking aggressive and persistent eye rubbing.
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We see this type of eye rubbing in some patients with mental incapacities.
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When the eye is rubbed aggressively and excessively over time, it can cause repeated trauma to the cornea, which can increase the chances of developing keratoconus.
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Another environmental exposure, chronic allergies.
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I live in Atlanta, so I know a lot about allergies.
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Like a lot.
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Severe allergic reactions lead to inflammation on the surface of the eye, and this chronic inflammation can potentially weaken and damage the cornea.
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What is really fascinating is the tears of patients with keratoconus have been examined to see if they can give us clues as to what is going on with this disease.
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These tears have been found to have lots of inflammatory mediators in them, making us believe there is an underlying inflammatory component.
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What a great idea to check the tears.
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After all, tears make a lot of contact with the cornea.
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So what would make a cornea inflamed?
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Those allergies and eye rubbing we discussed, also sun exposure and ill-fitting contact lenses.
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Yet another reason us contact lens wearers need an annual eye exam and one contact lens holiday day a week.
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Symptoms.
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Young patients are so active, so busy with life, and so invincible in their approach to life.
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Getting diagnosed with a disease like keratoconus means slowing down, lots of doctors' appointments, and a profound realization of our body's vulnerability.
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Something my patients who are 75 years old have already come to understand, but something that can be quite demoralizing for my 25-year-old patients.
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Unfortunately, keratoconus usually begins when we are teenagers or in our early 20s.
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It is progressive, meaning it keeps getting worse until we reach our 30s, when it finally tends to stabilize.
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I have had patients, though, who are still progressing into their 50s.
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Someone with keratoconus will have progressively blurry vision, but more than that, they will have progressively distorted vision.
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This is due to the significant astigmatism they develop, that we will discuss in the next session.
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Keratoconus also unfortunately develops in both eyes, but it is usually asymmetric, so one eye will be affected much more than the other.
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Let's say you have keratoconus in one eye, but are only being watched for it in the second eye.
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How soon will the second eye show signs of the disease?
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Well, one very interesting study showed that 50% of the time, the other eye will develop the disease within 16 years.
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Diagnosis.
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For us ophthalmologists, keratoconous diagnosis involves looking for lots of signs named after the doctors who discovered and coined them.
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For example, when the cone-shaped cornea becomes really prominent, you can see it without using a microscope.
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You have a keratoconus patient look down.
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The cone will cause their lower lid to bulge forward in a V shape.
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We call this Munson's sign.
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Another interesting sign is when we doctors flash light on the temple side of the cornea.
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This light hits the protruding cornea, which acts like a lens that focuses the light onto the nose side of the cornea.
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This light appears on the nasal side of the cornea as a bright and sharply focused beam of light.
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This is called Razuti sign and means the keratoconus is moderate to severe.
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Other signs require us to use the slit lamp, that's our fancy upright microscope, because they are biomicroscopic.
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One such sign is called a Fleischer's ring.
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This is a circle of iron that gets deposited into the epithelium, that's the outermost layer of the cornea, surrounding the base or bottom of the cone.
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The circle can be partial or complete.
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It is golden brown, greenish, or reddish in color, and would be pretty if it didn't indicate the presence of a serious disease.
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We can also see votes striae in the cornea.
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These are very fine little lines at the back of the cornea behind the stroma and happen because of compression of a layer of tissue behind the corneal stroma.
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If we are sticking with a pregnancy analogy, these would look like teeny tiny stretch marks behind the cone.
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Everybody's prescription in glasses can fluctuate, but patients with keratoconus will develop progressive myopia or nearsightedness.
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They also develop astigmatism, meaning the cornea becomes lumpy bumpy instead of round and smooth.
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We can also diagnose patients with keratoconus without even looking at them.
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My attending did this when I was a medical student rotating through ophthalmology, and I thought he was an absolute wizard.
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How did he do it?
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He looked at the patient's pachymetry.
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This is a test where we measure the thickness of the central cornea.
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We are all born with a certain corneal thickness, and though measurements of this might fluctuate a bit from test to test, there should not be any major change in this value.
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In keratoconus, we do see a progressive change because the cornea is thinning, so the pachymetry numbers start to decrease.
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My attending then looked at the patient's corneal topography.
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What is that?
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If you have a corneal disease, it's something you should definitely understand how to read along with your doctor.
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When my daughter was two years old, we used to go to the children's museum, and her favorite exhibit was the sandbox.
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It had a projector above it that colored the sand based on how elevated it was.
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So when she took her little baby fingers and flattened all the sand out, it was blue and green.
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When she started to make little mounds or hills with the sand, the color on top would become warmer.
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Think oranges and reds when she made a mountain.
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When she made enough mountains, and much to her delight, little dinosaurs would be projected onto the sandbox to play.
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This is a topographer, an easy way for land developers to see where hills and valleys are at a glance based on their colors, or for eye doctors to understand the landscape of a patient's cornea, or for my sweet baby girl to marvel at her ability to affect her environment.
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Color coding allows us to see patterns very quickly we would otherwise miss if we were evaluating numbers.
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It allows us to see the forest for the trees.
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With corneal topography, the flatter the cornea is, the cooler the color.
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The steeper the cornea, the warmer the color.
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Patients with keratoconus, therefore, have very warm colors, and these show up at the bottom of the topographer as the cornea bulges out and down.
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So the top of a topographer might be green or yellow, but the bottom will be a bright orange or a deep red.
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That is the gold standard sign we clinicians look for.
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Treatment.
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Like most diseases, treatment depends on the stage of keratoconus you are in.
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And remember, this disease is progressive.
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Let me give you an example of a real life patient of mine who is so close to my heart.
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You see, she was the same age as I was when I first met her.
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In fact, our birthdays are only one day apart.
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When we first met, she was 35 years old.
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As I reviewed her medical records, I saw she was diagnosed with keratoconus when she was 18 years old.
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Actually, on her 18th birthday.
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Yikes! While I was grinning ear to ear drinking a cyperia with my mom and sister in Brazil to celebrate, she was receiving a life-changing diagnosis.
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At 19, her keratoconus could be corrected with glasses.
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It was mild and the astigmatism was not that bad because her cone was not that bad.
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Her parents gifted her adorable glasses on her birthdays from then on.
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When she went out, she wore soft contact lenses and the vision was just as good as with her glasses.
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She wore these on her first day of grad school, her first international trip, her first really great date.
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By the time she got to her grad school graduation, however, she herself had graduated to rigid gas permeable or hard contact lenses.
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You see, her vision got blurry, even when she was wearing glasses or contacts.
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Her cone was so steep the astigmatism it created became uneven.
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Most of the steepening was at the bottom of her cornea.
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Irregular astigmatism like this oftentimes cannot be corrected with glasses or soft contacts.
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However, rigid contacts can tackle irregular astigmatism.
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Soft contact lenses conform to the shape of your eye.
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Rigid contacts make your eye conform to their shape.
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You put the perfectly shaped contact on top of a lumpy, bumpy cornea.
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There is a layer of tear film that gets trapped between your own cornea and the smooth dome of the contact.
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This essentially makes your cornea behave like the round, well-shaped contact lens.
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And just like that, new cornea.
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Her vision could not be corrected to 2020, but it was what we all in the field call 20 good enough to live her life.
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When I went to a bunch of concerts and plays and happily sat in the nosebleed section to save some precious cash, she only went to one play or concert a year, but splurged on seats in the third row so she could actually see what was going on.
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Unfortunately, at 23 years old, my sweet patient could not comfortably wear the rigid gas permeable contact lenses.
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You see, these are smaller in diameter than the cornea.
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They glide around the front of the cornea as the patient blinks.
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With my patient's steepening cone, the hard contact lens simply would not stay put on her eye.
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She saw our contact lens specialist and was placed in scleral contact lenses.
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How are these different?
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Well, they are much, much larger.
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These contacts vault completely over the cornea, no matter how irregular it is, and land on the white portion of the eye next to the cornea.
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These contacts never actually touch the cornea itself.
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How does one get such a bulky contact lens onto the eye?
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Carefully! In all seriousness, this takes some practice.
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You have to pull your eyelids pretty far apart to put the contact lens on the eye.
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And before you place it on, you have to fill the contact lens with preservative-free saline.
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This is a critical step.
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The saline is what acts as the buffer between the lumpy bumpy cornea and the contact lens.
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It is what fills in the gaps to create a smooth surface.
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This is what get this is what gets rid of distortions, blurry vision, and glare.
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There's a second and equally important function of that saline.
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To understand this, imagine your cornea is your lawn.
00:21:28.640 --> 00:21:33.680
Imagine the scleral contact lens is a giant tarp you place over your lawn.
00:21:33.839 --> 00:21:36.960
Then you set your sprinklers to run like they normally do.
00:21:37.200 --> 00:21:40.160
One month later, your lawn is dead.
00:21:40.400 --> 00:21:45.200
It never received the water from the sprinkler system because the tarp was covering it.
00:21:45.359 --> 00:21:52.799
If your cornea is covered by a contact lens every day, tears your eye produces cannot reach your cornea to hydrate it.
00:21:53.039 --> 00:21:57.200
The saline you place in the contact lens will do just this for you.
00:21:57.839 --> 00:21:59.119
Back to my patient.
00:21:59.279 --> 00:22:03.599
When she Was in her mid-20s, her vision continued to decline.
00:22:03.839 --> 00:22:11.599
I was in medical school starting to really understand the progressive nature of some diseases, and she was living it.
00:22:11.839 --> 00:22:14.240
She was no longer 20 happy.
00:22:14.480 --> 00:22:16.720
She was about 2100.
00:22:16.960 --> 00:22:22.400
This is not legal to drive and a real problem for a young independent adult.
00:22:23.759 --> 00:22:28.319
She made the very scary decision to get eye surgery for her condition.
00:22:28.480 --> 00:22:35.759
She had a procedure called ICRS or intracorneal ring segments.
00:22:36.000 --> 00:22:46.079
In the surgery, tiny arc-shaped plastic pieces are inserted into the corneal stroma near the periphery, so outside the visual axis.
00:22:46.240 --> 00:22:49.519
These pieces help flatten the protruding cornea.
00:22:49.680 --> 00:22:54.000
While generally a safe surgery, she had every right to be scared.
00:22:54.160 --> 00:22:56.559
Every surgery can have complications.
00:22:56.799 --> 00:23:03.839
For ICRS, the plastic pieces can migrate and even extrude out of the cornea.
00:23:04.000 --> 00:23:06.720
They can create scarring or infection.
00:23:06.960 --> 00:23:16.319
Fortunately, none of these complications occurred for my patient, but she did have glare in dim lighting conditions and decided to give up nighttime driving.
00:23:16.640 --> 00:23:21.359
Fast forward eight years later, she was now 35 and seeing me.
00:23:21.599 --> 00:23:29.200
The ICRS surgery had helped slow down the progression of her disease, but it did not stop the progression.
00:23:29.440 --> 00:23:34.079
And one day she developed the dreaded corneal hydrops.
00:23:34.400 --> 00:23:40.799
This is where the back layer of the cornea called the decimase membrane gets so stressed it ruptures.
00:23:41.039 --> 00:23:46.400
The decimase is the corneal layer responsible for keeping fluid out of the cornea.
00:23:46.720 --> 00:23:50.960
Its rupturing is akin to a dam breaking.
00:23:51.119 --> 00:23:57.119
Fluid rushed into her cornea, creating pain, swelling, and a sudden decrease in vision.
00:23:57.279 --> 00:24:04.640
The swelling eventually went away, but it left a scar, smack dab in the middle of her visual axis.
00:24:04.960 --> 00:24:11.279
And this no amount of contact lenses or plastic arc rings was able to fix.
00:24:11.599 --> 00:24:14.400
She needed a corneal transplant.
00:24:14.640 --> 00:24:17.839
No, we cannot transplant an entire eyeball.
00:24:18.079 --> 00:24:23.039
Minority report is just a movie and not reflective of real life.
00:24:23.279 --> 00:24:26.880
We can, however, transplant certain parts of the eyeball.
00:24:27.039 --> 00:24:30.640
The cornea is one of the most commonly transplanted parts.
00:24:30.880 --> 00:24:40.319
A corneal transplant is subject to all the risks any other organ transplant is subject to: infection, rejection, failure.
00:24:40.640 --> 00:24:48.799
But unlike a heart, a cadaveric cornea is widely available, thanks to all the amazing organ donors out there.
00:24:49.039 --> 00:24:55.440
They do not need to be blood-typed or immunologically matched, so it is not difficult to find the tissue.
00:24:55.680 --> 00:24:59.759
We call corneal transplantation penetrating keratoplasty.
00:25:00.160 --> 00:25:09.519
It has a great chance of success when performed for keratoconus, a 98% success rate over five years grade.
00:25:09.839 --> 00:25:16.160
But it is a big surgery and requires long-term steroids, which can cause other complications down the road.
00:25:16.319 --> 00:25:22.799
For my 35-year-old who needed to see to chase after her two toddlers, it was a no-brainer decision.
00:25:22.960 --> 00:25:25.920
But one I hated she had to make.
00:25:28.319 --> 00:25:30.799
Corneal crosslinking.
00:25:32.799 --> 00:25:40.160
In comes corneal crosslinking, one of the greatest recent technological advancements in our field.
00:25:40.400 --> 00:25:41.039
Why?
00:25:41.279 --> 00:25:47.839
Because it can keep people like my patient from needing a corneal transplant or any surgery for that matter.
00:25:48.079 --> 00:25:54.319
Corneal crosslinking can keep keratoconus from progressing in a really meaningful way.
00:25:54.720 --> 00:25:56.720
And it is not hard to do.
00:25:56.960 --> 00:25:59.759
It's actually an in-office procedure.
00:26:00.000 --> 00:26:02.720
You don't need to go to the operating room.
00:26:02.960 --> 00:26:06.319
Crosslinking cannot reverse the corneal bulge.
00:26:06.400 --> 00:26:14.079
It is only preventative, so it is important to get this done on patients early if their keratoconus is showing signs of progression.
00:26:14.319 --> 00:26:15.279
How early?
00:26:15.519 --> 00:26:18.559
It can be done on someone over 14 years of age.
00:26:18.799 --> 00:26:26.000
Even though it is a preventative procedure, one-third of patients do notice an improvement in their vision.
00:26:26.240 --> 00:26:27.519
How does it work?
00:26:27.759 --> 00:26:30.640
A patient gets riboflavin drops.
00:26:30.799 --> 00:26:33.519
These are vitamin B2 drops.
00:26:33.759 --> 00:26:42.000
Then specially designed UV light is applied to the cornea, and this hardens those stromal fibers, the plywood planks.
00:26:42.480 --> 00:26:44.640
This keeps them from bulging.
00:26:44.960 --> 00:26:50.480
The treatment takes about one hour to do and it can keep a patient from needing a corneal transplant.
00:26:50.720 --> 00:26:51.759
How much so?
00:26:52.000 --> 00:27:00.480
Studies show anywhere from a 25 to 50% reduction in the chances you might need a corneal transplant.
00:27:00.720 --> 00:27:03.119
That, folks, is significant.
00:27:03.359 --> 00:27:08.240
It stops disease progression in about 90% of patients.
00:27:09.119 --> 00:27:10.559
And listen to this.
00:27:10.880 --> 00:27:18.720
Patients who have had crosslinking spend roughly 28 years less in the advanced stages of the disease.
00:27:18.880 --> 00:27:22.559
That is 28 years of better vision.
00:27:22.880 --> 00:27:26.799
You know something is safe and effective if two things happen.
00:27:27.039 --> 00:27:33.839
One, the FDA approves it, and yes, corneal crosslinking is an FDA-approved procedure.
00:27:34.079 --> 00:27:36.720
And two, if insurance covers it.
00:27:36.960 --> 00:27:44.079
Medicare usually covers the procedure, and about 95% of commercial insurances provide coverage for this.
00:27:44.319 --> 00:27:48.000
You just need to document progression over the last two years.
00:27:48.240 --> 00:27:56.960
Even though it is covered by insurance, patients still spend out of pocket about$2,500 to$4,000 per eye.
00:27:57.200 --> 00:28:00.319
This has to do with deductibles and coinsurances.
00:28:00.559 --> 00:28:01.759
Sound like a lot?
00:28:01.920 --> 00:28:03.119
It is a lot.
00:28:03.440 --> 00:28:10.559
But it pales in comparison to the amount spent by a keratoconus patient who gets a corneal transplant.
00:28:10.799 --> 00:28:16.720
That, folks, is around$38,000 in their lifetime.
00:28:17.039 --> 00:28:25.519
If you or someone you know gets diagnosed with keratoconus, make sure they start talking with their doctor early about crosslinking.
00:28:25.680 --> 00:28:29.759
Remember, with prevention, the earlier the better.
00:28:32.319 --> 00:28:33.440
Conclusion.
00:28:35.599 --> 00:28:42.319
I hope you can appreciate that the cornea of the eye is much more than simply window dressing.
00:28:42.480 --> 00:28:47.119
It is, in fact, probably the most important window you will ever know.
00:28:47.359 --> 00:28:53.759
When this beautiful structure loses its integrity, the result can be devastating vision loss.
00:28:54.000 --> 00:29:00.480
And this suffering is all the more frustrating when we as doctors have to watch our patients get worse over time.
00:29:00.720 --> 00:29:10.160
But the great news with keratoconus is we can now do something prophylactically to stabilize this disease with corneal crosslinking.
00:29:10.400 --> 00:29:23.920
What a medical game changer! This could be the difference between a 30-year-old spending their anniversary traveling through Europe instead of convalescing after a corneal transplant surgery.
00:29:24.240 --> 00:29:28.240
I have loved spending another episode with you, dear listener.
00:29:28.400 --> 00:29:32.319
Until next time, see well and be well.
00:29:58.799 --> 00:30:00.240
Why a blueberry?
00:30:00.720 --> 00:30:05.599
Because blue is my favorite color, and blueberries are really yummy.
00:30:06.000 --> 00:30:07.359
Well, that's a good reason.
00:30:07.519 --> 00:30:12.240
If you had to say an eyeball is like a vegetable, what vegetable would it be like?
00:30:12.640 --> 00:30:14.160
A green bean.
00:30:14.640 --> 00:30:16.319
Why a green bean?
00:30:16.880 --> 00:30:23.519
Because my favorite vegetable is a green bean, and they're my second favorite color.
00:30:24.160 --> 00:30:24.480
Okay.
00:30:25.119 --> 00:30:27.519
Very good reasons to give your answer.
00:30:27.680 --> 00:30:28.799
Thank you, my love.
00:00:00.959 --> 00:00:04.240
Hello, my name is Parl Kator MD.
00:00:04.320 --> 00:00:09.839
I'm an ophthalmologist in Atlanta, Georgia, specializing in cataract and glaucoma surgeries.
00:00:10.080 --> 00:00:18.160
After practicing medicine for over a decade, I have learned that the more a patient knows about their disease, the better they do.
00:00:18.399 --> 00:00:21.359
Patient education is a passion of mine.
00:00:21.519 --> 00:00:26.800
But like most doctors, I have a lot of patients and not a lot of time to see them.
00:00:27.039 --> 00:00:36.079
So I created this podcast where I could spend the time I don't have during the day to give you insights into the eyeball and ocular disease.
00:00:36.320 --> 00:00:40.240
Let's empower you as a patient or a patient support system.
00:00:40.479 --> 00:00:44.320
Together, let's demystify the eye.
00:01:10.560 --> 00:01:14.079
Punny Halloween costumes are the bee's knee.
00:01:14.480 --> 00:01:20.640
One of the best Halloween costumes I have ever seen was one of these types of costumes.
00:01:20.799 --> 00:01:27.439
One of my residents had a tiny orange parking cone on her head, secured with a little rubber band strap.
00:01:27.599 --> 00:01:30.799
She was dressed in all black and was holding a carrot.
00:01:31.040 --> 00:01:34.719
No one at our work party, not a single person got it.
00:01:34.959 --> 00:01:40.159
She pointed to her carrot, then her hat, and said, Carrot a conus.
00:01:40.879 --> 00:01:42.239
Keratonus.
00:01:42.560 --> 00:01:44.319
A terrible disease.
00:01:44.799 --> 00:01:46.719
A brilliant costume.
00:01:52.319 --> 00:01:53.519
Statistics.
00:01:54.239 --> 00:02:01.680
Keratoconus comes from two Greek words, keras meaning cornea, and conus meaning cone.
00:02:01.920 --> 00:02:08.159
Together, these words perfectly describe this disease, which is a cone-shaped cornea.
00:02:08.400 --> 00:02:10.879
So is keratoconus worth talking about?
00:02:11.199 --> 00:02:14.319
How many people even have this disease worldwide?
00:02:14.560 --> 00:02:18.400
Well, over 23 million people.
00:02:18.960 --> 00:02:24.000
So yes, keratoconus is certainly worth talking and learning about.
00:02:24.240 --> 00:02:28.400
The statistic that always gets me is the age at diagnosis.
00:02:28.719 --> 00:02:39.840
This disease affects young people with an average age of diagnosis when a person is in their teens or early 20s, 16 to 25 years old to be exact.
00:02:40.080 --> 00:02:50.080
This is the time when our young people are just getting ready to embark on their life journeys, and this diagnosis changes the course of those lives.
00:02:50.479 --> 00:02:59.520
We do not believe keratoconus prefers men or prefers women, but there has been a particularly high prevalence in black females.
00:03:00.000 --> 00:03:05.680
This makes sense when you consider Africa as one of the highest populations of keratoconus.
00:03:05.840 --> 00:03:15.280
An updated review of keratoconus was published in 2022 and it showed Africa, India, and the Middle East as hotspots for this disease.
00:03:15.599 --> 00:03:21.199
Europe and North America had low prevalence rates, with Denmark having one of the lowest.
00:03:21.520 --> 00:03:26.400
Keratoconus is bilateral, which means it affects both eyes.
00:03:26.639 --> 00:03:31.360
It is often asymmetric, with one eye being affected more than the other.
00:03:31.599 --> 00:03:35.199
We know family history is a strong risk factor.
00:03:35.439 --> 00:03:46.159
Depending on the study you look at, if you have a first degree relative with keratoconus, you have a six to twenty five greater chance of having the disease yourself.
00:03:46.400 --> 00:03:47.919
25 times.
00:03:48.400 --> 00:03:49.919
That is huge.
00:03:52.800 --> 00:03:54.879
Pathophysiology.
00:04:00.319 --> 00:04:04.240
We had a professor there who specialized in neuroophthalmology.
00:04:04.479 --> 00:04:09.039
This is the connection between the optic nerve in the very back of the eye to the brain.
00:04:09.280 --> 00:04:12.639
We would ask her what she thought about cornea specialists.
00:04:12.800 --> 00:04:16.079
They specialize in the clear front portion of the eye.
00:04:16.319 --> 00:04:20.399
She was famous for retorting, how would I know?
00:04:20.560 --> 00:04:22.480
I'm not a window dresser.
00:04:22.800 --> 00:04:28.000
It was funny at the time, but mostly because the cornea is the window to the eye.
00:04:28.160 --> 00:04:34.720
It is the crystal clear dome at the very front portion of the eye that light hits first upon entering the eye.
00:04:34.959 --> 00:04:39.279
It is one of the two powerhouse refractors of the eye.
00:04:39.519 --> 00:04:52.959
This means it is one of the two structures that takes those parallel beams of light and makes them converge into one fine point on the retina in the back of the eye, allowing us to have the sharp vision we so desire.
00:04:53.360 --> 00:05:01.439
As the window of the eye, it is a hugely important structure, and doctors who specialize in it are not to be dismissed.
00:05:01.680 --> 00:05:12.399
When this structure goes awry, it can be in the form of cloudiness, such as with a corneal scar, or fuchendothelial dystrophy, another podcast episode in this season.
00:05:12.639 --> 00:05:18.560
If it remains crystal clear but loses its shape, diseases like keratoconus emerge.
00:05:18.800 --> 00:05:21.279
So what shape is a cornea supposed to be?
00:05:21.519 --> 00:05:23.759
It's supposed to be a sphere.
00:05:24.079 --> 00:05:26.000
Think of the epicot center.
00:05:26.240 --> 00:05:31.120
A beautiful, perfect sphere will make it so you don't need any glasses growing up.
00:05:31.360 --> 00:05:35.120
If the sphere is a little too steep, you are nearsighted.
00:05:35.199 --> 00:05:39.279
And if the sphere is a little too flat, you are far-sighted.
00:05:39.519 --> 00:05:46.319
If the sphere looks more like a football cut in half than a basketball cut in half, you have astigmatism.
00:05:46.560 --> 00:05:50.399
These are called refractive errors, and they can be fixed pretty easily.
00:05:50.560 --> 00:05:54.959
Listen to my podcast on refractive errors for more information about this.
00:05:55.279 --> 00:06:01.920
But what if this beautiful Epcot basketball disco ball sphere begins to bulge outwards?
00:06:02.160 --> 00:06:10.399
Imagine, if you will, a bunch of workers on the inside of a round cornea, putting their hands up to it and pushing with all their might.
00:06:10.639 --> 00:06:15.279
If the cornea bulges forward, it looks more like a cone than a sphere.
00:06:15.439 --> 00:06:19.199
When the cornea bulges, it gets thinner and steeper.
00:06:19.360 --> 00:06:31.439
Once light hits this cone, it gets bent into all sorts of wonky angles that have no chance of converging together into a fine point on the retina in the back of the eye.
00:06:31.680 --> 00:06:34.000
Light gets scattered everywhere.
00:06:34.240 --> 00:06:36.480
And this is kerataconus.
00:06:36.720 --> 00:06:40.639
One final important detail about the cornea is its layers.
00:06:40.959 --> 00:06:49.040
My sister is from Florida, and as I've noticed with most Floridians, she has become completely intolerant to the cold.
00:06:49.199 --> 00:06:56.079
I'm talking to the point she packs her ski outfit when visiting me in Atlanta if the weather is under 50 degrees.
00:06:56.319 --> 00:06:59.920
We recently went for a hike in Austin during a winter freeze.
00:07:00.079 --> 00:07:06.079
The temperature was 38 degrees, but with a wind factor, it felt like 27 degrees.
00:07:06.319 --> 00:07:14.000
I got to witness my sister preparing for said hike with one of the most fascinating displays of layering I have ever seen.
00:07:14.240 --> 00:07:18.639
I meanwhile had on sweatpants, a long-sleeve shirt, and a jacket.
00:07:18.879 --> 00:07:26.480
Forty-five minutes after she began dressing, we left the hotel room only for her to exclaim, Wow, it's colder than I expected.
00:07:26.720 --> 00:07:29.519
Better add another layer and run back in.
00:07:29.839 --> 00:07:35.839
The cornea's layers do what my sister was trying to do, protect herself from the elements.
00:07:36.000 --> 00:07:42.959
The cornea has six layers, and we will be focusing today on the middle layer or stroma of the cornea.
00:07:43.199 --> 00:07:45.839
This layer makes up the majority of the cornea.
00:07:46.000 --> 00:07:50.000
It accounts for about 80 to 85% of its thickness.
00:07:50.160 --> 00:07:54.879
It has parallel lines of collagen, peppered with keratocytes.
00:07:55.120 --> 00:08:00.399
Those are really beautiful star-shaped cells that maintain and support the stroma.
00:08:00.720 --> 00:08:05.199
The parallel lines in the cornea are important to remember for this podcast.
00:08:05.439 --> 00:08:12.959
To picture them, think about going to your neighborhood construction store and seeing those giant bundles of stacked plywood.
00:08:13.120 --> 00:08:17.120
Like plywood, the stroma of the cornea gives it its strength.
00:08:17.279 --> 00:08:22.079
But unlike plywood, the stroma of the cornea is crystal clear.
00:08:26.879 --> 00:08:30.000
No one knows exactly what causes keraticon.
00:08:30.480 --> 00:08:35.200
Does that sound frustrating to you, especially if you have it or know someone who does?
00:08:35.440 --> 00:08:38.480
Trust me, it's frustrating for your doctor too.
00:08:38.720 --> 00:08:46.559
We doctors admire the human body for the mysteries it contains, but we also hate a mystery we cannot solve.
00:08:46.879 --> 00:08:49.440
We do think there is a genetic component.
00:08:49.679 --> 00:08:50.080
Why?
00:08:50.240 --> 00:08:58.320
Because one in ten people with keratoconus has a parent with it, and that's just too high of a ratio to be due to chance.
00:08:58.559 --> 00:09:07.519
Additionally, scientists are now discovering a number of genes thought to contribute to the development of this disease and are still discovering more.
00:09:07.840 --> 00:09:11.440
But we also know that environmental factors play a role.
00:09:11.679 --> 00:09:15.919
What can people do or be exposed to that could create this?
00:09:16.159 --> 00:09:18.320
Well, we know of several.
00:09:18.559 --> 00:09:20.399
The first is eye rubbing.
00:09:20.720 --> 00:09:26.080
Oh my god, you're thinking, I rub my eyes like every morning when I wake up.
00:09:26.320 --> 00:09:29.519
Could I be creating keratoconus for myself?
00:09:30.000 --> 00:09:39.759
No, no, I'm not talking about general, your eye is itchy, so you rub it, or you just woke up and want to get the crust out of your eyes eye rubbing.
00:09:39.919 --> 00:09:44.559
I'm talking aggressive and persistent eye rubbing.
00:09:44.720 --> 00:09:49.200
We see this type of eye rubbing in some patients with mental incapacities.
00:09:49.360 --> 00:10:00.000
When the eye is rubbed aggressively and excessively over time, it can cause repeated trauma to the cornea, which can increase the chances of developing keratoconus.
00:10:00.240 --> 00:10:03.919
Another environmental exposure, chronic allergies.
00:10:04.240 --> 00:10:08.000
I live in Atlanta, so I know a lot about allergies.
00:10:08.240 --> 00:10:09.200
Like a lot.
00:10:09.440 --> 00:10:18.720
Severe allergic reactions lead to inflammation on the surface of the eye, and this chronic inflammation can potentially weaken and damage the cornea.
00:10:18.960 --> 00:10:28.240
What is really fascinating is the tears of patients with keratoconus have been examined to see if they can give us clues as to what is going on with this disease.
00:10:28.480 --> 00:10:37.039
These tears have been found to have lots of inflammatory mediators in them, making us believe there is an underlying inflammatory component.
00:10:37.279 --> 00:10:39.679
What a great idea to check the tears.
00:10:39.919 --> 00:10:43.200
After all, tears make a lot of contact with the cornea.
00:10:43.440 --> 00:10:45.840
So what would make a cornea inflamed?
00:10:46.080 --> 00:10:52.799
Those allergies and eye rubbing we discussed, also sun exposure and ill-fitting contact lenses.
00:10:53.039 --> 00:11:01.360
Yet another reason us contact lens wearers need an annual eye exam and one contact lens holiday day a week.
00:11:04.080 --> 00:11:05.039
Symptoms.
00:11:17.919 --> 00:11:24.559
Young patients are so active, so busy with life, and so invincible in their approach to life.
00:11:24.799 --> 00:11:34.720
Getting diagnosed with a disease like keratoconus means slowing down, lots of doctors' appointments, and a profound realization of our body's vulnerability.
00:11:34.960 --> 00:11:44.720
Something my patients who are 75 years old have already come to understand, but something that can be quite demoralizing for my 25-year-old patients.
00:11:45.039 --> 00:11:51.279
Unfortunately, keratoconus usually begins when we are teenagers or in our early 20s.
00:11:51.519 --> 00:11:58.559
It is progressive, meaning it keeps getting worse until we reach our 30s, when it finally tends to stabilize.
00:11:58.799 --> 00:12:03.519
I have had patients, though, who are still progressing into their 50s.
00:12:03.759 --> 00:12:11.279
Someone with keratoconus will have progressively blurry vision, but more than that, they will have progressively distorted vision.
00:12:11.519 --> 00:12:17.519
This is due to the significant astigmatism they develop, that we will discuss in the next session.
00:12:17.840 --> 00:12:27.039
Keratoconus also unfortunately develops in both eyes, but it is usually asymmetric, so one eye will be affected much more than the other.
00:12:27.279 --> 00:12:32.240
Let's say you have keratoconus in one eye, but are only being watched for it in the second eye.
00:12:32.480 --> 00:12:35.600
How soon will the second eye show signs of the disease?
00:12:35.840 --> 00:12:44.799
Well, one very interesting study showed that 50% of the time, the other eye will develop the disease within 16 years.
00:12:47.279 --> 00:12:48.720
Diagnosis.
00:12:50.480 --> 00:12:59.279
For us ophthalmologists, keratoconous diagnosis involves looking for lots of signs named after the doctors who discovered and coined them.
00:12:59.519 --> 00:13:06.240
For example, when the cone-shaped cornea becomes really prominent, you can see it without using a microscope.
00:13:06.399 --> 00:13:08.879
You have a keratoconus patient look down.
00:13:09.039 --> 00:13:13.039
The cone will cause their lower lid to bulge forward in a V shape.
00:13:13.279 --> 00:13:15.759
We call this Munson's sign.
00:13:16.320 --> 00:13:21.519
Another interesting sign is when we doctors flash light on the temple side of the cornea.
00:13:21.759 --> 00:13:29.039
This light hits the protruding cornea, which acts like a lens that focuses the light onto the nose side of the cornea.
00:13:29.360 --> 00:13:35.919
This light appears on the nasal side of the cornea as a bright and sharply focused beam of light.
00:13:36.080 --> 00:13:41.360
This is called Razuti sign and means the keratoconus is moderate to severe.
00:13:41.600 --> 00:13:49.840
Other signs require us to use the slit lamp, that's our fancy upright microscope, because they are biomicroscopic.
00:13:50.000 --> 00:13:52.799
One such sign is called a Fleischer's ring.
00:13:52.960 --> 00:14:01.759
This is a circle of iron that gets deposited into the epithelium, that's the outermost layer of the cornea, surrounding the base or bottom of the cone.
00:14:01.919 --> 00:14:04.320
The circle can be partial or complete.
00:14:04.480 --> 00:14:12.720
It is golden brown, greenish, or reddish in color, and would be pretty if it didn't indicate the presence of a serious disease.
00:14:13.039 --> 00:14:16.799
We can also see votes striae in the cornea.
00:14:16.960 --> 00:14:26.799
These are very fine little lines at the back of the cornea behind the stroma and happen because of compression of a layer of tissue behind the corneal stroma.
00:14:27.039 --> 00:14:33.519
If we are sticking with a pregnancy analogy, these would look like teeny tiny stretch marks behind the cone.
00:14:33.759 --> 00:14:41.679
Everybody's prescription in glasses can fluctuate, but patients with keratoconus will develop progressive myopia or nearsightedness.
00:14:41.840 --> 00:14:48.320
They also develop astigmatism, meaning the cornea becomes lumpy bumpy instead of round and smooth.
00:14:48.639 --> 00:14:53.360
We can also diagnose patients with keratoconus without even looking at them.
00:14:53.600 --> 00:15:01.519
My attending did this when I was a medical student rotating through ophthalmology, and I thought he was an absolute wizard.
00:15:01.679 --> 00:15:02.799
How did he do it?
00:15:03.039 --> 00:15:05.440
He looked at the patient's pachymetry.
00:15:05.679 --> 00:15:09.519
This is a test where we measure the thickness of the central cornea.
00:15:09.759 --> 00:15:19.759
We are all born with a certain corneal thickness, and though measurements of this might fluctuate a bit from test to test, there should not be any major change in this value.
00:15:20.000 --> 00:15:28.240
In keratoconus, we do see a progressive change because the cornea is thinning, so the pachymetry numbers start to decrease.
00:15:28.480 --> 00:15:31.840
My attending then looked at the patient's corneal topography.
00:15:32.080 --> 00:15:33.039
What is that?
00:15:33.279 --> 00:15:40.080
If you have a corneal disease, it's something you should definitely understand how to read along with your doctor.
00:15:40.639 --> 00:15:47.919
When my daughter was two years old, we used to go to the children's museum, and her favorite exhibit was the sandbox.
00:15:48.080 --> 00:15:53.120
It had a projector above it that colored the sand based on how elevated it was.
00:15:53.360 --> 00:15:59.360
So when she took her little baby fingers and flattened all the sand out, it was blue and green.
00:15:59.600 --> 00:16:05.919
When she started to make little mounds or hills with the sand, the color on top would become warmer.
00:16:06.240 --> 00:16:09.360
Think oranges and reds when she made a mountain.
00:16:09.519 --> 00:16:17.279
When she made enough mountains, and much to her delight, little dinosaurs would be projected onto the sandbox to play.
00:16:17.600 --> 00:16:35.279
This is a topographer, an easy way for land developers to see where hills and valleys are at a glance based on their colors, or for eye doctors to understand the landscape of a patient's cornea, or for my sweet baby girl to marvel at her ability to affect her environment.
00:16:35.600 --> 00:16:41.919
Color coding allows us to see patterns very quickly we would otherwise miss if we were evaluating numbers.
00:16:42.159 --> 00:16:45.039
It allows us to see the forest for the trees.
00:16:45.279 --> 00:16:49.519
With corneal topography, the flatter the cornea is, the cooler the color.
00:16:49.679 --> 00:16:52.240
The steeper the cornea, the warmer the color.
00:16:52.399 --> 00:17:02.000
Patients with keratoconus, therefore, have very warm colors, and these show up at the bottom of the topographer as the cornea bulges out and down.
00:17:02.320 --> 00:17:09.440
So the top of a topographer might be green or yellow, but the bottom will be a bright orange or a deep red.
00:17:09.599 --> 00:17:13.119
That is the gold standard sign we clinicians look for.
00:17:15.440 --> 00:17:16.400
Treatment.
00:17:18.559 --> 00:17:23.599
Like most diseases, treatment depends on the stage of keratoconus you are in.
00:17:23.839 --> 00:17:26.720
And remember, this disease is progressive.
00:17:26.880 --> 00:17:32.480
Let me give you an example of a real life patient of mine who is so close to my heart.
00:17:32.720 --> 00:17:36.880
You see, she was the same age as I was when I first met her.
00:17:37.039 --> 00:17:40.799
In fact, our birthdays are only one day apart.
00:17:41.039 --> 00:17:43.759
When we first met, she was 35 years old.
00:17:43.920 --> 00:17:50.400
As I reviewed her medical records, I saw she was diagnosed with keratoconus when she was 18 years old.
00:17:50.720 --> 00:17:53.599
Actually, on her 18th birthday.
00:17:53.839 --> 00:18:04.319
Yikes! While I was grinning ear to ear drinking a cyperia with my mom and sister in Brazil to celebrate, she was receiving a life-changing diagnosis.
00:18:04.559 --> 00:18:08.240
At 19, her keratoconus could be corrected with glasses.
00:18:08.400 --> 00:18:13.200
It was mild and the astigmatism was not that bad because her cone was not that bad.
00:18:13.359 --> 00:18:17.759
Her parents gifted her adorable glasses on her birthdays from then on.
00:18:17.920 --> 00:18:23.519
When she went out, she wore soft contact lenses and the vision was just as good as with her glasses.
00:18:23.759 --> 00:18:31.200
She wore these on her first day of grad school, her first international trip, her first really great date.
00:18:31.440 --> 00:18:41.039
By the time she got to her grad school graduation, however, she herself had graduated to rigid gas permeable or hard contact lenses.
00:18:41.359 --> 00:18:46.720
You see, her vision got blurry, even when she was wearing glasses or contacts.
00:18:46.960 --> 00:18:51.440
Her cone was so steep the astigmatism it created became uneven.
00:18:51.680 --> 00:18:55.039
Most of the steepening was at the bottom of her cornea.
00:18:55.200 --> 00:19:01.759
Irregular astigmatism like this oftentimes cannot be corrected with glasses or soft contacts.
00:19:01.920 --> 00:19:06.079
However, rigid contacts can tackle irregular astigmatism.
00:19:06.400 --> 00:19:10.000
Soft contact lenses conform to the shape of your eye.
00:19:10.240 --> 00:19:14.079
Rigid contacts make your eye conform to their shape.
00:19:14.319 --> 00:19:18.720
You put the perfectly shaped contact on top of a lumpy, bumpy cornea.
00:19:18.880 --> 00:19:25.359
There is a layer of tear film that gets trapped between your own cornea and the smooth dome of the contact.
00:19:25.680 --> 00:19:30.400
This essentially makes your cornea behave like the round, well-shaped contact lens.
00:19:30.480 --> 00:19:33.200
And just like that, new cornea.
00:19:33.519 --> 00:19:42.400
Her vision could not be corrected to 2020, but it was what we all in the field call 20 good enough to live her life.
00:19:42.640 --> 00:19:57.920
When I went to a bunch of concerts and plays and happily sat in the nosebleed section to save some precious cash, she only went to one play or concert a year, but splurged on seats in the third row so she could actually see what was going on.
00:19:58.319 --> 00:20:05.599
Unfortunately, at 23 years old, my sweet patient could not comfortably wear the rigid gas permeable contact lenses.
00:20:05.839 --> 00:20:09.200
You see, these are smaller in diameter than the cornea.
00:20:09.279 --> 00:20:12.640
They glide around the front of the cornea as the patient blinks.
00:20:12.799 --> 00:20:18.799
With my patient's steepening cone, the hard contact lens simply would not stay put on her eye.
00:20:19.039 --> 00:20:24.079
She saw our contact lens specialist and was placed in scleral contact lenses.
00:20:24.240 --> 00:20:25.839
How are these different?
00:20:26.079 --> 00:20:29.039
Well, they are much, much larger.
00:20:29.279 --> 00:20:38.400
These contacts vault completely over the cornea, no matter how irregular it is, and land on the white portion of the eye next to the cornea.
00:20:38.559 --> 00:20:42.000
These contacts never actually touch the cornea itself.
00:20:42.160 --> 00:20:45.839
How does one get such a bulky contact lens onto the eye?
00:20:46.160 --> 00:20:51.039
Carefully! In all seriousness, this takes some practice.
00:20:51.200 --> 00:20:55.839
You have to pull your eyelids pretty far apart to put the contact lens on the eye.
00:20:56.000 --> 00:21:01.039
And before you place it on, you have to fill the contact lens with preservative-free saline.
00:21:01.279 --> 00:21:02.799
This is a critical step.
00:21:02.960 --> 00:21:08.400
The saline is what acts as the buffer between the lumpy bumpy cornea and the contact lens.
00:21:08.559 --> 00:21:13.279
It is what fills in the gaps to create a smooth surface.
00:21:13.519 --> 00:21:20.400
This is what get this is what gets rid of distortions, blurry vision, and glare.
00:21:20.640 --> 00:21:24.640
There's a second and equally important function of that saline.
00:21:24.799 --> 00:21:28.400
To understand this, imagine your cornea is your lawn.
00:21:28.640 --> 00:21:33.680
Imagine the scleral contact lens is a giant tarp you place over your lawn.
00:21:33.839 --> 00:21:36.960
Then you set your sprinklers to run like they normally do.
00:21:37.200 --> 00:21:40.160
One month later, your lawn is dead.
00:21:40.400 --> 00:21:45.200
It never received the water from the sprinkler system because the tarp was covering it.
00:21:45.359 --> 00:21:52.799
If your cornea is covered by a contact lens every day, tears your eye produces cannot reach your cornea to hydrate it.
00:21:53.039 --> 00:21:57.200
The saline you place in the contact lens will do just this for you.
00:21:57.839 --> 00:21:59.119
Back to my patient.
00:21:59.279 --> 00:22:03.599
When she Was in her mid-20s, her vision continued to decline.
00:22:03.839 --> 00:22:11.599
I was in medical school starting to really understand the progressive nature of some diseases, and she was living it.
00:22:11.839 --> 00:22:14.240
She was no longer 20 happy.
00:22:14.480 --> 00:22:16.720
She was about 2100.
00:22:16.960 --> 00:22:22.400
This is not legal to drive and a real problem for a young independent adult.
00:22:23.759 --> 00:22:28.319
She made the very scary decision to get eye surgery for her condition.
00:22:28.480 --> 00:22:35.759
She had a procedure called ICRS or intracorneal ring segments.
00:22:36.000 --> 00:22:46.079
In the surgery, tiny arc-shaped plastic pieces are inserted into the corneal stroma near the periphery, so outside the visual axis.
00:22:46.240 --> 00:22:49.519
These pieces help flatten the protruding cornea.
00:22:49.680 --> 00:22:54.000
While generally a safe surgery, she had every right to be scared.
00:22:54.160 --> 00:22:56.559
Every surgery can have complications.
00:22:56.799 --> 00:23:03.839
For ICRS, the plastic pieces can migrate and even extrude out of the cornea.
00:23:04.000 --> 00:23:06.720
They can create scarring or infection.
00:23:06.960 --> 00:23:16.319
Fortunately, none of these complications occurred for my patient, but she did have glare in dim lighting conditions and decided to give up nighttime driving.
00:23:16.640 --> 00:23:21.359
Fast forward eight years later, she was now 35 and seeing me.
00:23:21.599 --> 00:23:29.200
The ICRS surgery had helped slow down the progression of her disease, but it did not stop the progression.
00:23:29.440 --> 00:23:34.079
And one day she developed the dreaded corneal hydrops.
00:23:34.400 --> 00:23:40.799
This is where the back layer of the cornea called the decimase membrane gets so stressed it ruptures.
00:23:41.039 --> 00:23:46.400
The decimase is the corneal layer responsible for keeping fluid out of the cornea.
00:23:46.720 --> 00:23:50.960
Its rupturing is akin to a dam breaking.
00:23:51.119 --> 00:23:57.119
Fluid rushed into her cornea, creating pain, swelling, and a sudden decrease in vision.
00:23:57.279 --> 00:24:04.640
The swelling eventually went away, but it left a scar, smack dab in the middle of her visual axis.
00:24:04.960 --> 00:24:11.279
And this no amount of contact lenses or plastic arc rings was able to fix.
00:24:11.599 --> 00:24:14.400
She needed a corneal transplant.
00:24:14.640 --> 00:24:17.839
No, we cannot transplant an entire eyeball.
00:24:18.079 --> 00:24:23.039
Minority report is just a movie and not reflective of real life.
00:24:23.279 --> 00:24:26.880
We can, however, transplant certain parts of the eyeball.
00:24:27.039 --> 00:24:30.640
The cornea is one of the most commonly transplanted parts.
00:24:30.880 --> 00:24:40.319
A corneal transplant is subject to all the risks any other organ transplant is subject to: infection, rejection, failure.
00:24:40.640 --> 00:24:48.799
But unlike a heart, a cadaveric cornea is widely available, thanks to all the amazing organ donors out there.
00:24:49.039 --> 00:24:55.440
They do not need to be blood-typed or immunologically matched, so it is not difficult to find the tissue.
00:24:55.680 --> 00:24:59.759
We call corneal transplantation penetrating keratoplasty.
00:25:00.160 --> 00:25:09.519
It has a great chance of success when performed for keratoconus, a 98% success rate over five years grade.
00:25:09.839 --> 00:25:16.160
But it is a big surgery and requires long-term steroids, which can cause other complications down the road.
00:25:16.319 --> 00:25:22.799
For my 35-year-old who needed to see to chase after her two toddlers, it was a no-brainer decision.
00:25:22.960 --> 00:25:25.920
But one I hated she had to make.
00:25:28.319 --> 00:25:30.799
Corneal crosslinking.
00:25:32.799 --> 00:25:40.160
In comes corneal crosslinking, one of the greatest recent technological advancements in our field.
00:25:40.400 --> 00:25:41.039
Why?
00:25:41.279 --> 00:25:47.839
Because it can keep people like my patient from needing a corneal transplant or any surgery for that matter.
00:25:48.079 --> 00:25:54.319
Corneal crosslinking can keep keratoconus from progressing in a really meaningful way.
00:25:54.720 --> 00:25:56.720
And it is not hard to do.
00:25:56.960 --> 00:25:59.759
It's actually an in-office procedure.
00:26:00.000 --> 00:26:02.720
You don't need to go to the operating room.
00:26:02.960 --> 00:26:06.319
Crosslinking cannot reverse the corneal bulge.
00:26:06.400 --> 00:26:14.079
It is only preventative, so it is important to get this done on patients early if their keratoconus is showing signs of progression.
00:26:14.319 --> 00:26:15.279
How early?
00:26:15.519 --> 00:26:18.559
It can be done on someone over 14 years of age.
00:26:18.799 --> 00:26:26.000
Even though it is a preventative procedure, one-third of patients do notice an improvement in their vision.
00:26:26.240 --> 00:26:27.519
How does it work?
00:26:27.759 --> 00:26:30.640
A patient gets riboflavin drops.
00:26:30.799 --> 00:26:33.519
These are vitamin B2 drops.
00:26:33.759 --> 00:26:42.000
Then specially designed UV light is applied to the cornea, and this hardens those stromal fibers, the plywood planks.
00:26:42.480 --> 00:26:44.640
This keeps them from bulging.
00:26:44.960 --> 00:26:50.480
The treatment takes about one hour to do and it can keep a patient from needing a corneal transplant.
00:26:50.720 --> 00:26:51.759
How much so?
00:26:52.000 --> 00:27:00.480
Studies show anywhere from a 25 to 50% reduction in the chances you might need a corneal transplant.
00:27:00.720 --> 00:27:03.119
That, folks, is significant.
00:27:03.359 --> 00:27:08.240
It stops disease progression in about 90% of patients.
00:27:09.119 --> 00:27:10.559
And listen to this.
00:27:10.880 --> 00:27:18.720
Patients who have had crosslinking spend roughly 28 years less in the advanced stages of the disease.
00:27:18.880 --> 00:27:22.559
That is 28 years of better vision.
00:27:22.880 --> 00:27:26.799
You know something is safe and effective if two things happen.
00:27:27.039 --> 00:27:33.839
One, the FDA approves it, and yes, corneal crosslinking is an FDA-approved procedure.
00:27:34.079 --> 00:27:36.720
And two, if insurance covers it.
00:27:36.960 --> 00:27:44.079
Medicare usually covers the procedure, and about 95% of commercial insurances provide coverage for this.
00:27:44.319 --> 00:27:48.000
You just need to document progression over the last two years.
00:27:48.240 --> 00:27:56.960
Even though it is covered by insurance, patients still spend out of pocket about$2,500 to$4,000 per eye.
00:27:57.200 --> 00:28:00.319
This has to do with deductibles and coinsurances.
00:28:00.559 --> 00:28:01.759
Sound like a lot?
00:28:01.920 --> 00:28:03.119
It is a lot.
00:28:03.440 --> 00:28:10.559
But it pales in comparison to the amount spent by a keratoconus patient who gets a corneal transplant.
00:28:10.799 --> 00:28:16.720
That, folks, is around$38,000 in their lifetime.
00:28:17.039 --> 00:28:25.519
If you or someone you know gets diagnosed with keratoconus, make sure they start talking with their doctor early about crosslinking.
00:28:25.680 --> 00:28:29.759
Remember, with prevention, the earlier the better.
00:28:32.319 --> 00:28:33.440
Conclusion.
00:28:35.599 --> 00:28:42.319
I hope you can appreciate that the cornea of the eye is much more than simply window dressing.
00:28:42.480 --> 00:28:47.119
It is, in fact, probably the most important window you will ever know.
00:28:47.359 --> 00:28:53.759
When this beautiful structure loses its integrity, the result can be devastating vision loss.
00:28:54.000 --> 00:29:00.480
And this suffering is all the more frustrating when we as doctors have to watch our patients get worse over time.
00:29:00.720 --> 00:29:10.160
But the great news with keratoconus is we can now do something prophylactically to stabilize this disease with corneal crosslinking.
00:29:10.400 --> 00:29:23.920
What a medical game changer! This could be the difference between a 30-year-old spending their anniversary traveling through Europe instead of convalescing after a corneal transplant surgery.
00:29:24.240 --> 00:29:28.240
I have loved spending another episode with you, dear listener.
00:29:28.400 --> 00:29:32.319
Until next time, see well and be well.
00:29:58.799 --> 00:30:00.240
Why a blueberry?
00:30:00.720 --> 00:30:05.599
Because blue is my favorite color, and blueberries are really yummy.
00:30:06.000 --> 00:30:07.359
Well, that's a good reason.
00:30:07.519 --> 00:30:12.240
If you had to say an eyeball is like a vegetable, what vegetable would it be like?
00:30:12.640 --> 00:30:14.160
A green bean.
00:30:14.640 --> 00:30:16.319
Why a green bean?
00:30:16.880 --> 00:30:23.519
Because my favorite vegetable is a green bean, and they're my second favorite color.
00:30:24.160 --> 00:30:24.480
Okay.
00:30:25.119 --> 00:30:27.519
Very good reasons to give your answer.
00:30:27.680 --> 00:30:28.799
Thank you, my love.
