Knock Knock Eye: Would You Risk Blindness for Blue Eyes?
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hi that's aka.ms slash knock knock hi hello welcome everybody to knock knock i with me your host dr glockenflecken this is your weekly update in the world of eyeballs all right we're we've got a great lineup today all right i'm going to start with um i should just label this opening segment like

What's new with UnitedHealthcare? Because since I last recorded an episode, I've learned some things. Some more terrible things have come out about this company. And so it just needs to be like a running segment. I swear to God, every week something new comes out about UnitedHealthcare. So we'll go over that. I'm going to talk a bit about infrared contact lenses.

night vision contacts what what is this all about uh and then we'll get to a deep dive into a part of the eye you guys really liked i did the deep dive into the cornea recently uh and and so i'm going to keep doing it different different eyeball uh parts of the eye and so we're going to do the iris today today is a deep dive into the iris i'm going to tell you all about the iris

the anatomy, the physiology, diseases that can go wrong with everything, the embryology of irises, of your irides, which is what we ophthalmologists like to call it because it makes us sound smarter.

I-R-I-D-E-S, irides, as well as how the iris relates to some of the oldest pseudoscience grifting there is out there. So jam-packed. And then at the end, if we have time, I'm going to get to some of your questions and provide some answers. All right, so first, oh boy.

This was huge. You know, the last time I recorded, I talked about how UnitedHealthcare, their stock was down by like, it's like 50%. I don't know. It seems to be more and more. They're struggling as a company. People are fed up with everything that they're doing. And then I read an article that came out of The Guardian.

Uh, we all know that, you know, nursing homes is like where if there's going to be shenanigans going on in, in, in healthcare, chances are it's going to, unfortunately you're going to find it in nursing homes because.

It's just an, and it's, it's a, there are places that are, that are overlooked, uh, you know, that, that aren't, that don't, um, draw a lot of attention. And so if, if an insurance company has an idea of how they can, um, cheat people out of money.

or just cause all kinds of problems. I feel like they're going to trial some of their new types of, what do I call them? They're going to be trialing their new types of fraud at a nursing home. So it turns out that's exactly what was happening. So basically what UnitedHealthcare has been doing

is going to like nursing home administrators, people that work in the nursing homes, nurse practitioners, PAs, uh, primarily and convincing them to, to try to get patients to, to sign a DNR. And let me be, let me be clear here. I, I don't, I don't blame the, the,

I don't blame the, uh, the healthcare professionals here because, because if you have someone who's very much more powerful than you putting enough pressure on you, like maybe they take a little bit of blame, but the vast majority of it goes on these, these insurance companies, because there are executives within UnitedHealthcare that were pressuring people to get

Patients in nursing homes to sign in D.R. D.N.R. Do not resuscitate orders in order to save the insurance company money like this is this is this might be the worst thing I have heard come out of United Health Care in in the last like month at least. I mean, this is awful. This is this is absolutely terrible. When I said.

on this podcast and on social media everywhere, that insurance companies, they want to extract as much money from your healthy body as possible until you're no longer healthy. Then they want you to die as quickly as possible. This is exactly what I'm talking about. I said that as hyperbole, but it's quickly becoming not hyperbole. They're actually doing this.

They're trying to make their customers, people that have their Medicare Advantage plans, they're trying to, these seniors, they're trying to get them to be DNR so they won't have to pay for any admissions. As you get older, you use a lot more health care services that UnitedHealthcare has to pay for or they should be paying for because you've been paying into UnitedHealthcare.

But now they're like, oh, no, we don't want that. So let's try to get these people just to not live anymore. Come on. This is outrageous. Like, I feel like the tide is turning because every week there's more whistleblowers. There's more investigative journalism.

Guardian, ProPublica, people are doing the work on uncovering these things that they're doing that for decades have been under the surface, hidden away from the public. You know what sucks even more though, is that they're still making more and more profit.

Like what kind of world, this is America where like, we're like the most capitalistic country ever. And how is it that a company like UnitedHealthcare can clearly have a roughly 0% approval rating?

Find one person outside of the people that work for UnitedHealthcare, even most of them probably don't like it either, outside of the executive, outside of the sweet seat. Find me one person that has a favorable view of UnitedHealthcare. I'm not talking about the bots that come into my comment section, clearly aren't real people. They're like, I love my health insurance. It does great for me. No, it doesn't. It doesn't.

If it does for you, congratulations. I don't believe you. But if it does, you know, that means you're like part of the 0.001% that actually has a functioning relationship with their health insurance company. Get out there and talk to like real people, the vast majority of people. How is it that this company can make more and more money, can profit greater heights of money, of profit,

yet have a 0% approval rating in a, in a company that in a, in a, in a country where, where you're a capitalistic country, how does that happen? All right. If people don't like you, if they don't like what you do, that should hurt business, but it's not, it's not. So it's, it's very frustrating to see happening and to see that they're trying to kill off people in nursing homes. And other than some bad press, uh,

What's going to happen? I think Congress is waking up a little bit more. I hope both sides, by the way, they're both interested that Arkansas did the PBM reform bill, the first of its kind, that was Republican-led. So we're talking both sides here. I think both sides are waking up and realizing that this is way out of control. Though no corporation should have this amount of power,

over people where they can just do shit like this and it's now out in the open. And now what's going to happen to them? If nothing happens, oh man, what do you do? Where do you go? Where do you go from here? You got to start passing laws, like real laws, real things that strip away power from this, from these corporations. But I won't hold my breath. We'll say that.

So anyway, that's the latest update. Go read that Guardian piece because it's shocking. I really appreciate all the people that are coming forward about this. A lot of this is whistleblower stuff. The only way we're going to get inside information into these corporations is if people who have been inside come forward and talk about it or through depositions from lawsuits. That's the only way we're going to get truthful information.

They're not going to offer up any of this stuff because they know it's damaging. They know what they're doing. They know it's bad. So anyway, that's the latest. Starting off angry. Thank goodness we're talking about something serene like the iris today. I love the irises. It's such a great part of the body. It really is. Before we get to that, though, one more thing. Recent news, healthcare news. I saw one of those

Popular science articles, you know, of that makes you think like the like something like an and like an eyeball transplants right around the corner, even though it's really not right. One of those like fantastical sounding things. This one is kind of believable, though. We have some researchers who are this is a new study in the journal Cell, which is a big one. It's a big journal.

that they're developing basically night vision goggles, but in contact lens form. So you just be able to, you know, how the vision looks like with night vision. Like that's infrared. You're seeing like there's a technology in those goggles that takes infrared light and somehow through magic and science and physics changes that infrared spectrum into an electromagnetic spectrum that the human eye can process.

Well, they're basically just taking that and trying to turn it into contact lenses.

And it's not there yet. Apparently, based on this article I'm reading, it's on its way. But the images you get through these contact lenses are really blurry or fuzzy. So you don't have the traditional night vision you would have with glasses. But it's on its way, which would be super cool. I think that would help a lot of people. Because a lot of diseases that have...

lots of night vision difficulty. But if you could just either put on a pair of glasses or put in some contacts that can maybe not get you seeing clearly, but at least give you some useful vision to navigate at night, that would make things a lot safer. Whether or not you can drive with them. I mean, that's another thing. But anyway, it's just kind of cool to see stuff like this. That actually is within the realm of possibility. So I'm excited to see where this one goes. Infrared contact.

contact lenses and able you to see at night. That would be really, really cool. All right, let's take a break. Hey, Kristen. Yeah.

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Okay, the moment you've all been waiting for. A deep dive into the iris. Plural of iris. You can say irises. That's fine. That's how a non-ophthalmologist would say it. Just irises. You're irises. We would say irides.

Irradiate in a very, in a deep kind of knowledgeable voice. The irides are pathologic. I don't know. That's a phrase I've never said before, but I could, I could, and it would make sense coming out of my mouth as an ophthalmologist. Anyway, the iris, this thin annular structure that's in most mammals and birds have them. Sometimes they're different shapes. Have you seen the iris of a goat? It's a square.

How does that happen? I don't know. Maybe I should talk to a veterinarian. Let's get one on. Someone wants to talk to me about square irises or why goat eyes look like that. Maybe I'll just try to do some research, try to figure it out on my own. But I'd love a comment, by the way. Comment on the YouTube channel at Glockenfleckens. All right. Go to the all these are posted on there on the YouTube channel. Leave a comment.

Let me know. I'd love to feature your thoughts on this podcast. Help teach the people about goat eyes, please. I'm a veterinarian out there. All right, so the iris is extremely important. Just big picture. There's a disease called aniridia without iris. You don't have an iris. It causes all kinds of problems. Now, there's other diseases.

developmental abnormalities that come with with not having an iris like glaucoma and cataract and foveal hypoplasia where you you don't have a developed fovea so it causes you to lose vision but also not having an iris it causes lots of problems because functionally here's what the iris does it helps to limit the amount of light that comes into the eye

which you need because when it's dark outside, your iris is going to dilate. We'll explain how this happens here in a little bit. But when there's lots of light, your iris is going to get real small pinpoint, all right? Because you want to limit the amount of light. You modulate the amount of light so it's not too much, so it's not damaging to your rods and cones, which are very delicate, delicate structures. But if you don't have a lot of light, if you're in the dark,

All right, you don't have your infrared night vision goggles, then your pupil is going to dilate that pupil to allow as much light as you can get into the eye to activate the rods and get some night vision going. All right, so structurally, the iris.

Two layers. You have the fibrovascular layer, the layer that contains all the muscles, and then behind that you have the pigmented layer. So you have the stroma, and then you have the pigment epithelial cells. The pigment epithelial cells are actually

in the back layer of the iris. So when you're looking at someone's iris, you're actually, and you're seeing the pigment, the color to their iris, you're seeing basically the amount of pigment is in the iris, but that's in the back part. You're actually seeing through the stroma, which is a very thin, thin structure. So within the stroma, you have two muscles. I've already alluded to them already. You have the sphincter muscle. You got a sphincter in your eye. You got sphincters elsewhere.

All sphincters, they do different things, but they're sphincters nonetheless. So it's something that my GI colleagues and I have in common. We both deal in sphincter medicine. Now, they probably deal a little bit more in sphincter medicine than I do. I don't have a lot of patients that have sphincter-related problems. It does happen, though. There's a variety of different reasons. But you have a sphincter muscle, which contracts the pupil.

It's kind of situated in a circle. It's right near the border of the iris. When you look at someone's pupil, where the iris begins, right around the pupil, that's the border. That's where, right in there, is where your sphincter muscle is. That's where it constricts, right at the border of the pupil. And then you have the dilator muscle, the dilator pupillae, or the sphincter pupillae.

The dilator pupillae, it pulls the iris radially. So it's a longer muscle and it just opens up the, I'm making a hand movement on YouTube. It opens up the iris radially to enlarge the pupil and it pulls it out. You get these folds in it. So let's talk about how pupil constriction and dilation actually works. What the innervation of these, because we have the muscles, how are they innervated? So your pupil dilator,

All right. What opens up the pupil that is, is regulated by your sympathetic nervous system. So when we put dilating drops in your eyes, we are putting in a drop that activates the sympathetic nervous system causes the pupil to open up. All right. We also conversely block your parasympathetic nervous system.

Because the parasympathetics is what causes the pupil to constrict. And so your pupil constrictor muscles is activated by parasympathetics, your pupil dilator by sympathetics. And so if we wanted to dilate the pupil, not only can we stimulate those sympathetics, stimulate that pupil dilator muscle, but we also block activation of the pupil constrictor muscle.

So that's why we give you two different drops when we dilate you. We give you phenylephrine or, yeah, basically phenylephrine. And we also give you tropicamide, which is a parasympathetic blocking medicine, anti-parasympathetic.

So the sympathetic nervous system, it starts in your hypothalamus. It goes all the way down your kind of your internal carotid, all the way down to the cervical ganglion, then back up into your eye. There's a disease that can affect your sympathetic nervous system, and that is called Horner syndrome. Anywhere along that pathway of those sympathetics,

If there's anything that disrupts that sympathetic pathway, then it'll cause you to have a Horner syndrome. And classically, can you guess what you would see if you had something that disrupted the parasympathetics? You would have a constricted pupil. You have what's called meiosis, M-I-O-S-I-S.

not to be confused with meiosis, which is, isn't that the replication of germ cells? I think that's, if I remember my basic biology, meiosis, I don't know exactly how you're supposed to say it, but anyway, that's a constricted pupil. That's what you would see with a Horner syndrome where you have damage along the parasympathetics. Oh, sorry, damage along the sympathetics. Conversely,

If you have damage to the parasympathetics, and there's also a pathway there going from the, you have this Edinger-Westphal nucleus. I'm not going to go into the details of the exact pathway, but the classic one that we're always so worried about is when you have damage to the parasympathetic pathway to the cranial nerve three pathway, which is what carries the nerves down.

that innervate the pupil constricting muscle would be an aneurysm, an intracranial aneurysm in the circle of Willis. All right, so that's something if we see a pupil that's dilated abnormally, the pupil is bigger, that's one thing that's on the differential. All right, there's lots of things we can think about, but we're not worried about that because right now we're just talking about the iris. That's what's important here.

So anyway, that's, that's your, if you just remember constricting is parasympathetics, dilating is sympathetics. All right. And when one of those, when you get damaged to one of those pathways, the opposite thing occurs.

Um, another thing that people constriction also helps to do. So that parasympathetic pathway, what people constriction also allows you to do is it changes your depth of field. It allows you to do what's called accommodate. So when you go from looking in the distance and you can look at this, like you can record yourself doing this, focus your eye or unfocus your eyes, I should say, looking far around the distance. Now, this really only works if you're, if you're

like farsighted or don't have much of a glasses prescription, but you can do it with while you're wearing your glasses as well or contacts. So look out in the distance as far as you can, and then very quickly change your focal point to something really close, like a foot from your nose. Put your finger right there. Look out in the distance at a tree and then quickly look at your finger. You know what you're going to notice is that your pupil constricts.

That constriction helps you to change the shape. You're basically using the ciliary muscles inside the eye that are just adjacent to your pupil that causes the lens in the eye to change shape and allows you to focus up close. And pupil constriction is a part of that pathway.

So the iris contracts the pupil when accommodation is initiated and that increases your depth of field, allows you to see up close. And that's something that we lose over the course of our life. Really in your like mid forties, that's when it begins and it just gets kind of worse and worse. And it's, it's a bane to everyone's existence. Nobody likes that. All right. So,

talked about anatomy, physiology, what does the iris do, and let's talk, before we get into eye color, let's talk about what happens, so I mentioned aniridia, a disease where you don't have an iris, or you really just have a little nub of an iris, but

But there's lots of things that can happen that can cause lots of diseases that can cause you to lose parts of your iris. Obviously, trauma can do it. All right. We have people that have had major trauma to the eye. They can lose part of their iris or they have enough inflammation in the eye that it causes the iris to kind of degenerate. The iris is a very delicate tissue. And so.

And if that happens, patients will get really severe light sensitivity, right? Because again, the iris, part of the purpose of it is to block the amount of light. Well, if you have damage to the iris,

then more light's going to get into the eye and cause lots of glare issues, light sensitivity. And so this can happen during surgery. Even during uncomplicated, like routine surgery, like cataract surgery, sometimes, you know, we mess around with the iris and we don't mean to, but it can happen. In fact, one of my

mentors, my biggest mentor and residency always said, no matter what, whatever you do, don't mess with the iris because that is a delicate structure that can really cause maybe not blindness for people, but certainly if you mess with it enough, it can cause lots of glare issues and just generally just people just unhappy with the quality of their vision because it's such an important part of the eye.

Okay. So, um, and other things that can cause you to, you know, trauma, obviously there, there are really certain rare diseases that, uh, like genetic diseases that can cause degeneration of the, of the iris. Um, there are certain diseases. There's one called pigment dispersion syndrome. This is one where, uh,

The lens that sits behind the iris starts to chafe away at the pigment cells in the back of the iris we talked about, right? You have the stroma in the front, pigment in the back. Well, the lens, which sits right behind it, if your anatomy is such that there's not enough space between the iris and the lens, and that can happen normally for people, then you can get chafing as the iris moves in and out with dilation and constriction.

that releases all this pigment. It just rubs off the pigment. And if you rub off enough of that pigment, then you're actually going to be able to see right through the iris. You just, it sloughs off and you have more transparency, what we call transillumination defects of the iris. And that can cause glare problems. That can make people pretty unhappy. Lots of different reasons why you could lose that pigment. But since we're talking about pigment,

Let's, let's just quickly discuss eye color. So eye color is, uh, it's kind of fascinating, really, uh, color. It really just depends on how much, um, how much pigment you have. So people with very little pigment, you're going to have more of a lighter color. You're going to have a, you're, that's when you're, you get your, your blues, your, uh, your greens. But if you have really dark eyes, you have a lot of pigment and this is all genetically determined. Um,

And there are some diseases that give you what's called heterochromia, where you have one pupil, one iris, that is darker or lighter than the other. And maybe the darker iris is the abnormal one. Maybe the lighter iris is the abnormal one.

So I mentioned Horner syndrome. Well, with congenital Horner syndrome, you can get one iris that's lighter colored than the other. That's a sign of a congenital Horner syndrome. At some point in development, there was damage to the sympathetic chain that caused there to be less pigment deposition in the iris on that side. And that's because pigment deposition in the iris is sympathetically mediated. So that's a sign of a congenital Horner's. You can have

You can be on certain medications. Here's a common one. So often we'll prescribe people a medication called latanoprost. It's a glaucoma medication.

Well, one of the side effects of this medication is that it can cause one pupil or whatever, whichever eye you're taking it in, if it's both eyes, and it would happen in both pupils, but you can actually get a darker color. It can cause your eyes to darken a little bit. So I always warn people about that, especially people who already have, who have lighter colored eyes. I just warn them, your eyes could get a little bit darker if you're on this medication, this latanoprost long-term.

And so that's a known side effect. But I think, you know, especially when you're looking into the microscope, eyes are just gorgeous. Like, I just, I love dark colored eyes, light colored eyes, which drives me, which is why it drives me crazy when people undergo dangerous procedures like eye color change surgery. All right. There's a couple of, in fact, let's take a quick break. We'll come back and I'll talk about the grifting that occurs with irises.

So, Will. Yeah. You're always teaching me things about Demodex mites, your little friends there. Let's switch things up a bit. Okay. How about I ask you a couple questions to see how much you really know? Go for it. Okay. Let's do it. What are the only two main species of Demodex mites found in humans? Oh.

Type 1 and type 2? Hmm, got you on that one. Demodex follicularum, which are found in the eyelash follicles, and demodex brevis, which are found in the meibomian glands. Impressive. All right, next question. Why do people with demodex blepharitis often feel itchy eyelids first thing in the morning? I know this because I use it to gross you out. Demodex mites avoid light and they come out mostly at night to mate.

and move between your eyelash follicles. So many people will wake up with that itchy, irritated feeling along their eyelids. So gross.

I'm surprised you even brought that up. I know. I know. I'm just trying to get used to these mites since demodex blepharitis is such a common disease and we keep talking about it. Well, that's a big step. And we know there's a prescription eye drop available to treat demodex blepharitis. To learn more about these mites and demodex blepharitis, visit miteslovelids.com for more information. Again, that's M-I-T-E-S-L-O-V-E.

E-L-I-D-S.com to learn more. This ad is brought to you by Tarsus Pharmaceuticals. All right, two grifting things. One is more dangerous than the other. The first is eye color change surgery. I have talked about this on this podcast probably a few times, but I'll just say it again. All right, there are people that do this. I think they're ophthalmologists. Not totally sure.

Probably are, especially if they're doing the U S but, um, what they will do is they'll make you pay a whole lot of money and they'll take it. They don't change your eye color. What they're doing is they're taking an artificial Iris that has a different color. They're putting it inside the eye and it just sits right on top of your natural Iris.

That's all it is. It's like you're putting on a mask, but instead of your entire face, it's just in front of your natural iris. So if you have dark brown eyes, you can put like an artificial iris that sits right on top of your normal iris that's a blue color.

But guess what? It doesn't look natural. It's never going to look natural because it's artificial. It don't look that good. Okay. Also, it's dangerous. You're undergoing this procedure that is not very well tested. It's not, I don't, I mean, it is FDA approved, but not for this purpose. And because you, you know, artificial, an artificial iris can be helpful for people like aniridia who don't have an iris, who,

Their quality of their life would be so much better if they had an iris, but not for artificially just a cosmetic eye color change surgery. Don't do it because your eyes are beautiful. Your eyes are amazing. Doesn't matter what color they are. All color irises look incredible. And so don't change it. Don't shell out all this money for something that could blind you because there are people that have gone blind from this. And shame on any physician who's doing this type of surgery to people.

just for cosmetic purposes. I don't like you. Please stop. The other thing, the other type of grifting that occurs with iris is in the world of homeopathy, alternative medicine, whatever you want to call it. It's called iridology. Iridology is a technique, they call it a technique, whose proponents, people who believe in this, they think that the patterns, color, and other

characteristics of the iris can be examined to determine information about a patient's systemic health. So because you have like a fold in your iris at eight o'clock, that means that you're going to have prostate cancer in 10 years, that kind of nonsense. People believe this stuff. They really do. It's like fortune telling. It's like, like palm reading. I would say it's not as nefarious because it's,

It's a novelty, but unfortunately, like people will believe some of this stuff. But I would say it's not quite as bad as someone putting an artificial iris in someone's eye.

Okay, folks, other things. Let's see. How about some random iris knowledge? You can get whenever you have inflammation in the eye. There's lots of reasons why that can happen. You can have a thing called uveitis. You can have infections in the eye. Basically, anytime there's inflammation in the eye, the iris does not like that. And what will happen is you'll get scarring.

And the iris itself will kind of, will form scar tissue down onto the lens, cause what's called synechia. So you can get scar tissue featuring the iris and angle closure glaucoma. There's a lot of diagnoses that involve the iris.

uh, that we've gone through in the course of this podcast. Uh, but I think I've, I've told you everything. Um, I think you need to know about the iris. I I'll have more to say about some of the other parts of the eye. Um, uh, we'll do, let's see, we, we gotta do the lens as a cataract surgeon. I gotta do the lens. We can do the anterior chamber angle. We could just talk about aqueous. Would that excite you all just sit here and talk about the aqueous for 35 minutes.

I could do it. I could do it. I don't know how exciting that episode will be. Obviously, you may have to devote two episodes to the retina because the retina is very complicated. But we could do it. So anyway, we've got lots of great deep dives into different parts of the eye coming up.

uh, speaking of the Irish, I do have a couple of, uh, comments that were really good a lot. Cause I want to try to do at least one, maybe have time for a couple of these comments here. So I asked on our YouTube channel that I'm loving. I said, I love it. All the comments and questions from you guys keep them coming. Are there any topics you want me to cover? And I got some good suggestions. So here's a good question at, um,

Les Homos Dupilly. Sorry, I don't know how to say your name. Hey, I have an eyeball question. I always wondered if there is a physiologic reason the retina has flipped receptors. Why aren't the receptors in the other direction? So let me tell you about it. So I think what you're talking about is the fact that there are layers to the retina and your licensing cells, your photoreceptors are actually at the back end of the retina.

So you have to look through like six or seven different layers. The light has to penetrate through six or seven different layers until it finally gets back to the photoreceptors. And I've thought about this before. I remember thinking about this in residency. Why would the photoreceptors not be closer to the light source? Why do you have to, why do you make the light go through six or seven different layers? They're very small layers, but they're layers nonetheless. Why do you make them to go through all of these layers

To get to the photoreceptors, which are the light-sensing cells in the retina, why not just have the photoreceptors be the first cell layer that the light hits on its way through the eye? Well, the reason for that is because the photoreceptors require a lot of ATP, a lot of energy, proteins. There's a lot of turnover there.

a lot of electrical impulses and action potentials happening, which requires lots of energy. And where do the photoreceptors get that energy? They get it from the choroid, which is a very vascular tissue right next to the photoreceptors on the outer part of the eye. So if you put the photoreceptors more interior, closer to the light coming into the eye, then you'd move it away from its light source.

That's why. That's why the photoreceptors are where they are. I hope that answered your question. At Laura Lee 394, I want to hear more about the optic nerve. Here's a real good one for you. Homonymous hemianopia.

Oh, that's a good one. Hemianopia, homonymous hemianopia, hemianopia. That's a bigger topic. I think I've addressed it before, but basically, real quick, the 30-second version is when you have a stroke or a lesion affecting parts of your cerebral cortex, then because of where the pathways are of the nerve fibers going from your eye to your brain,

then you can cut basically just cut out you can lose half of your vision so for your right eye it would be like the right part of your vision for your left eye would also be the right part of your vision but the end result is that you lose a complete half of your visual field that's what's called an homonymous heminopia and when we talk maybe we'll do a deep dive into the pathways of

the vision pathway kind of posterior to the eyeball. I don't, I don't get outside the eyeball very often you guys, but when I do, I stick to the vision pathway. So maybe we'll do a deep dive a little bit later in the next few weeks or months on the, um, the, uh, the, just the vision pathway. Once you get into the brain behind the eye, that's a great question though. Thank you, Lori.

One more. We'll see. At Elizabeth K2595 says, why does a vitrectomy cause a cataract, but the lasers for LASIK don't? That's a great question. So on a physiologic level, I'm not sure I really know why a vitrectomy causes a cataract. So I mentioned this. A vitrectomy is when you go inside the eye and you suck out all that vitreous humor.

That's what fills the back part of your eye. You have about five milliliters of vitreous humor back there. A vitrectomy involves removing all that. But most importantly, you're going inside the eye. When you introduce instruments into the eye and you use the type of energy, the old type of ultrasound energy that it requires to remove that jelly, remove that vitreous, what it also does is it

Somehow, physiologically, it causes opacity and progression of cataractogenesis in the human lens. So somehow that energy inside the eye that you're putting in there, trying to remove all that vitreous, it causes a cataract to progress. It kind of ramps up the aging process of the eye, all right?

As far as the physiology behind that, I'm not totally sure. I should probably know that. I've never actually really thought more deeply about why that happens, but it does. But the reason, to get your question though, the reason why LASIK doesn't do it is because with LASIK, you're actually not going inside the eye.

LASIK is done on the surface of the eye. You're cutting into the cornea, but you're not cutting all the way through the cornea. So the inside structures of the eye, like the cataract, like your lens, which is where the cataract is,

um, are preserved. They're pristine. They're not affected at all because you at, with the laser, you're not going, or at least you should not be going inside the eye with a laser, um, with, uh, with the LASIK laser. We do have other lasers that do go inside the eye, but generally for a surgery to progress a cataract, it needs to be operating inside the eye. And typically it's a vitrectomy that does that. Good question. All right.

I think we'll call it a day. That's it. Thank you, guys. I'm going to get to more of your questions later. I appreciate everybody. And obviously, you can also give me your thoughts on UnitedHealthcare. I love hearing the hate comments about UnitedHealthcare.

Tell me what you don't like. Also, are there any other insurance companies that are doing things that I should know about? Please let me know. I'd love to any big policy changes. I love highlighting those so that people can be more informed about their health insurance policy.

So happy to help. Obviously, any eyeball suggestions, any topic suggestions, I'll keep doing these deep dives on different parts of the eye. You can leave a comment again on our YouTube channel at Glockenfleckens. Thank you all for listening. I'm your host, Will Fennery, also known as Dr. Glockenflecken. Thanks to my executive producers, Aaron Corny, Rob Goldman, and Shanti Brick, editor and engineers, Jason Portiza. Our music is by Omer Benzvi. We'll see you next time, everyone.

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