Speaker 1: Brought to you by the reinvented two thousand twelve Camray.
Speaker 1: It's ready. Are you get in touch with technology with
Speaker 1: tech Stuff from how stuff works dot com. Hello everyone,
Speaker 1: welcome to tech Stuff. My name is Chris Polette, and
Speaker 1: I am an editor at how stuff works dot com.
Speaker 1: And I see sitting across from me as he typically is.
Speaker 1: I think I can't tell. I don't war my glasses on,
Speaker 1: but I think it's senior writer Jonathan Strickland. She'll be
Speaker 1: the same except for bionic eyes. She lost the real
Speaker 1: ones in the robot Wars. Nice. Thank you. Yeah. Today
Speaker 1: we're going to talk about laser eye surgery. We've had
Speaker 1: some people ask us about laser eye surgery and what
Speaker 1: goes into it and exactly how are leasers used in
Speaker 1: the process. But I think that's a record for your
Speaker 1: use of that version of lasers. Yeah, and so we're
Speaker 1: going to, uh, we're gonna kind of break it down
Speaker 1: and talk about it goes into a laser eye surgery procedure.
Speaker 1: And we should also mention I should mention that I
Speaker 1: am very close to someone who has had laser eye surgery,
Speaker 1: not right now, not like physically. I was going to
Speaker 1: say my wife. My wife had laser eye surgery, um,
Speaker 1: and she has been very happily moving around without the
Speaker 1: you need for glasses for several years now. Um. And
Speaker 1: it was very impressive to me because my wife is
Speaker 1: not the sort of person who typically likes people, uh
Speaker 1: you know, mesballs exactly. Yeah. She's that's not high on
Speaker 1: our list of things to do today, but she did
Speaker 1: it anyway. And we're going to kind of talk about
Speaker 1: the process and what you have to do in order
Speaker 1: to get laser eye surgery and what's actually being done
Speaker 1: to you. Yeah, and I think probably the best place
Speaker 1: to start is speaking of eyeballs, with the eyeball itself, yeah,
Speaker 1: and why you might need laser eye surgery in the
Speaker 1: first place, right, Uh. To to to understand this discussion,
Speaker 1: you have to have at least a basic geography of
Speaker 1: the eyeball. So let's talk a little bit about the eye. So,
Speaker 1: so your your eye. The outer coating is this sort
Speaker 1: of tough outer coating called the sclera, and that's sort
Speaker 1: of what keeps the eyeball in its shape. It's it's
Speaker 1: kind of the the well, it's just it's the outer layer.
Speaker 1: And then part of this outer layer about I think
Speaker 1: one sixth of it is the cornea, which is the
Speaker 1: clear outer layer that goes over the part of your
Speaker 1: eye where light actually passes through to get to you know,
Speaker 1: your eyeball. So the cornea is, uh, it's kind of
Speaker 1: like a window in a way, or if you want
Speaker 1: to think of it like a a tablet device or something.
Speaker 1: It's the gorilla glass. It's on the outside that texts
Speaker 1: the the the innards, and then behind the cornea. Well,
Speaker 1: first of all, you've got the sort of a watery,
Speaker 1: clear liquid called the aqueous humor. Yeah, this goes back
Speaker 1: to the old humor's uh idea that dates back centuries
Speaker 1: where we used to think that our bodies we were
Speaker 1: like we're governed by a well, a small group of
Speaker 1: various liquids called humors. We've somewhat developed beyond that at
Speaker 1: this point, although I do think it's it's funny that
Speaker 1: even now we are referring to this particular liquid as
Speaker 1: a humor. Yes, so, so the aqueous humor, it's it's
Speaker 1: this clear, clear liquid that's behind the cornea. It's also
Speaker 1: in front of the iris, and there's a little bit
Speaker 1: behind the iris as well. So then that leads to
Speaker 1: the question, what then is the iris. Well, that's the
Speaker 1: that's the color part of your eye. So for example,
Speaker 1: my iris is blue because it lacks a certain amount
Speaker 1: of pigmentation, which makes it a blue color. My wife's
Speaker 1: eyes are brown. And uh, this is the part of
Speaker 1: the other acts as like an adjustable diaphragm around the pupil.
Speaker 1: So the pupil is that's the dark center of your iris.
Speaker 1: That's the little opening actually that allows light to pass through, right,
Speaker 1: And of course that's the part that the uh enlarges
Speaker 1: or get smaller depending on the amount of light in
Speaker 1: the room. Yeah, it's it's it's really an ingenious kind
Speaker 1: of approach. Really. It's it's the same sort of thing
Speaker 1: that we do with cameras when we have an aperture,
Speaker 1: you know, the aperture of a camera. And you may
Speaker 1: remember this if you listen to our our podcast about
Speaker 1: slow motion. We talked about the aperture quite a bit. Uh.
Speaker 1: That's what allows you to adjust how much light comes
Speaker 1: in through the camera's lens and hits the sensor. Uh,
Speaker 1: same sort of idea here. The iris is what will
Speaker 1: expand or contract around the pupil and thus control the
Speaker 1: amount of light that comes in. So if you walk
Speaker 1: into a dark room, then the it's going to the
Speaker 1: the iris is going to allow more light to pass through.
Speaker 1: It's going to allow more of the pupil to be
Speaker 1: exposed so that you get more light so that you
Speaker 1: can maneuver through because you're gonna be able to you
Speaker 1: need to be able to see if you're in a
Speaker 1: really bright environment. In order to protect the eye, that
Speaker 1: diaphragm is gonna close around the pupil to restrict the
Speaker 1: amount of light that comes in. Right, and of course
Speaker 1: UM there there's more than one UM analog as far
Speaker 1: as the eye and a camera shut. We were talking
Speaker 1: about cameras not too long ago where we we talked
Speaker 1: about the lens and how light passes through the lens
Speaker 1: to the film on the other side, or or an
Speaker 1: image censor in the case of a digital camera. Well,
Speaker 1: in the eye, you've got the retina, which is um
Speaker 1: if you will, on the on the back side of
Speaker 1: the eye, which is what records the image as as
Speaker 1: the light comes through the pupil. Right, You've got you've
Speaker 1: got the pupil, that's the aperture. You also have a lens,
Speaker 1: right behind the pupil. Right, So the lens, the lens
Speaker 1: is what is focusing that light, directing that light so
Speaker 1: that it it hits the focal point ideally, which is
Speaker 1: the retina. And the retina contains certain kinds of cells,
Speaker 1: rod cells and cone cells. These are light censoring light sensors. Essentially, Um,
Speaker 1: he sells sense the presence of light, and uh, through
Speaker 1: a chemical reaction, send that information to your brain and
Speaker 1: then your brain says, hey, I recognize that that's a puppy. Also,
Speaker 1: at interesting point, if you weren't familiar with this, uh,
Speaker 1: the image that you see when you're looking at something
Speaker 1: when it hits your retina, it's actually inverted, just as
Speaker 1: it is in a camera. But yes, that's the So this,
Speaker 1: this is the basic part of the eye. Now, what
Speaker 1: happens when something is just not quite right? For example, Uh, Chris,
Speaker 1: I don't know. Are you near sighted or far sighted?
Speaker 1: I am myopic. I am also myopic. That means we
Speaker 1: are both near sighted, and since we both have our
Speaker 1: our glasses off at the moment, we're both a little blurry.
Speaker 1: So myopia means that the focal point is hitting. Uh,
Speaker 1: it's it's hitting before it gets to your retina. So
Speaker 1: inside your eye there's a you know, the light is
Speaker 1: being directed by the lens to your retina. Uh, those
Speaker 1: the points of light are all converging, right, and that
Speaker 1: point of convergence is the focal point. Now, the focal
Speaker 1: point for those with myopia is in front of the retina.
Speaker 1: It's not hating the retina just right. So that means
Speaker 1: that when we start looking around things, things tend to
Speaker 1: be the further way things are, the blurrier, they tend
Speaker 1: to be. Yes. Um, Now, this can happen through various uh,
Speaker 1: just well, irregularities. There could be irregularities in the cornea
Speaker 1: that can cause this to happen, or in the lens itself,
Speaker 1: or it could be that the eyeball itself is elongated. Yes,
Speaker 1: so that the you know, if the eyeball was not elongated,
Speaker 1: the focal point would be right there on the retina
Speaker 1: where it's supposed to be in Everything will be fine,
Speaker 1: but the eyeball has been stretched. Nice sound effect, thank you,
Speaker 1: doesn't necessarily Jonathan Strict lines, it doesn't necessarily mean that
Speaker 1: someone's actually gone in there and stretch your eyeball. It
Speaker 1: just means that that's kind of the way it developed. Um,
Speaker 1: now far sighting this, which is a hyperopia hyperropia, thank you,
Speaker 1: I'm glad you're ready for that. One's ready? Yeah, hyperopia.
Speaker 1: You've got the focal point that's that's actually behind the retina,
Speaker 1: so when the lights hitting hitting the retina, it's not
Speaker 1: converged on that point like it should be. And uh, hyperopia,
Speaker 1: if you're hyper hyperopic, would that be correct? Hyperopic? Then
Speaker 1: that would mean that you know, you would the the
Speaker 1: closer something is, the more out of focus it is,
Speaker 1: the further away it is, the clearer it is. Also
Speaker 1: in addition to being myopic, I also have an astigmatism,
Speaker 1: I too have an a stigmatism. I think he's just
Speaker 1: just you know, doesn't want me to have one more
Speaker 1: than he does. I only have one. Do you have
Speaker 1: to know? I'm saying, are you and have an a stigmatism?
Speaker 1: Me too? Me too? It just it happen anyway. And
Speaker 1: and an a stigmatism, Um, you have a difference in
Speaker 1: the shape of your cornea or the lens. And basically
Speaker 1: what happens is it creates in effect two focal points
Speaker 1: within your eye. UM. And so basically that sort of
Speaker 1: confuses the way the light is traveling inside your eye,
Speaker 1: and that um, you can have, as we were both
Speaker 1: pointing out just a moment ago, you can have uh
Speaker 1: an a stigmatism on top of another eye condition. Yes,
Speaker 1: it's it's really an uneven curvature of the cornea or
Speaker 1: or lens, and yeah, it's it. It can cause problems.
Speaker 1: So the thing is that the humans are clever. Yeah,
Speaker 1: and we figured out a long time ago that if
Speaker 1: you use a lens of glass and it's curved just
Speaker 1: the right way, the curvature of the glass us can
Speaker 1: direct light so that it corrects for these problems. I
Speaker 1: can't imagine the amount of trial and error it took
Speaker 1: to be able to figure this out. But to correct
Speaker 1: your your vision, you have to, you know, take into
Speaker 1: account what the focal point is doing uh inside your eye.
Speaker 1: So with it's a little bit different between myopia and
Speaker 1: uh and hyperopia. But anyway, the curvature of the lens
Speaker 1: depends upon the condition, right, you know, if it's going
Speaker 1: to be a concave lens for one and a convex
Speaker 1: lens for the other, And honestly, I can't remember the
Speaker 1: one from the other. I guess I could stare at
Speaker 1: my glasses long enough and try and figure it out.
Speaker 1: But um, but the point being that that's what's going
Speaker 1: to direct the light the right way into your eye
Speaker 1: so that it corrects for whatever problem you already have.
Speaker 1: And then, of course, well what if we didn't want
Speaker 1: to wear glasses, what if we wanted something where it
Speaker 1: wasn't you know, this this pair of frames sitting on
Speaker 1: our face. Well that's when we started to come up, well,
Speaker 1: we could maybe make a lens that could sit directly
Speaker 1: on the eye and do the same sort of correction.
Speaker 1: It's going to require a more precise approach because it's
Speaker 1: going to be a much smaller lens that by definition,
Speaker 1: I mean you can't have an enormous lens shoved into
Speaker 1: your eye and expect any sort of comfort. So that's
Speaker 1: where the contact lens idea came from, where we started
Speaker 1: to kind of get you you apply these same kinds
Speaker 1: of thought to a thin lens that could fit directly
Speaker 1: on top of the eye. But then we thought, hey,
Speaker 1: wait a minute, we're really just talking about lenses here.
Speaker 1: Even even the cornea can act somewhat as a lens.
Speaker 1: The cornea on your eye itself directs light. So what
Speaker 1: if we were to reshape the cornia so that it
Speaker 1: corrected for whatever problems we had as you know, as
Speaker 1: far as vision problems are concerned. Uh, what if we
Speaker 1: just did that, then we wouldn't have to wear contact
Speaker 1: lenses or glasses or anything. And that's where the idea
Speaker 1: for corrective surgery comes from. And um, and at its
Speaker 1: very most basic level, what correct what this laser eye
Speaker 1: surgery is doing is it's altering the shape of the
Speaker 1: cornea so that directs light in a way that corrects
Speaker 1: for whatever vision problem you have. That's that's the basic
Speaker 1: you know, when you get down to it, that's what
Speaker 1: laser eye surgery is all about. So it's just it's
Speaker 1: that same principle behind grinding a lens so that you
Speaker 1: can see, you know, in a pair of eyeglasses, but
Speaker 1: now it's applied directly to our biology. It sadly does
Speaker 1: not mean you will actually end up with laser shooting
Speaker 1: out of your eyes, well at least not for most people. No,
Speaker 1: I would think that's a pretty rare side effect. So, yeah,
Speaker 1: where would you like to start with laser eye surgery? Well,
Speaker 1: I was going to talk about sort of the process
Speaker 1: you have to go through before you get laser eye
Speaker 1: surgery done, and then we'll get into what is actually
Speaker 1: going on in a laser eye surgery session. Yeah, because frankly,
Speaker 1: it's it's reminds me of a lot of life events.
Speaker 1: You know. The actual event itself doesn't really take all
Speaker 1: that long. Laser eye surgery only takes a few minutes.
Speaker 1: It can take less than half an hour total um.
Speaker 1: But there is quite a bit of preparation that needs
Speaker 1: that you need to go through beforehand to make sure
Speaker 1: that everything goes smoothly um and preferably not panicky, which
Speaker 1: is the reason that I haven't had it done. Yeah.
Speaker 1: So the first thing you have to do is you
Speaker 1: have to go through and we're talking about a reputable
Speaker 1: laser eye surgeon. This is a good time for us
Speaker 1: to point out there are a lot of different facilities
Speaker 1: out there that offer laser eye surgery services. Do your research. Yes,
Speaker 1: that's a great idea, because I know for a fact
Speaker 1: that there are there's a few in Atlanta that have
Speaker 1: a reputation for being less than honest, Like they'll the
Speaker 1: what the they do is they'll offer this amazing sounding deal.
Speaker 1: And of course we all know the phrase it sounds
Speaker 1: too good to be true. It was probably on the internet. Um,
Speaker 1: and the deal, the deal would be something like two
Speaker 1: d I, which is about a tenth of what some
Speaker 1: eye surgeries cost, you know, and you're thinking, wow, that's amazing,
Speaker 1: and then you know it's got an official sounding name
Speaker 1: and it's gonna be great. And then if you actually
Speaker 1: start doing some research, you'll see that there's often a
Speaker 1: lot of bait and switch involved where you'll go in
Speaker 1: and they'll do this initial I exam and then they'll say, oh, well,
Speaker 1: in your case, because you have this particular you know,
Speaker 1: condition or whatever, it's actually gonna be closer to undred
Speaker 1: per eye or and and just that alone is a
Speaker 1: you know, first of all, that's kind of a shady
Speaker 1: business practice. But beyond that, you don't want, you know,
Speaker 1: you don't know how far their ethics extend into say,
Speaker 1: not being a good doctor. So so in other words,
Speaker 1: do your research. Yeah, quack alert. So, assuming that the
Speaker 1: the facility has got a good reputation, uh, you go in,
Speaker 1: you would get a very thorough eye exam, probably more
Speaker 1: thorough in fact, I would are definitely more through than
Speaker 1: you would get going to just get a pair of
Speaker 1: glasses or contact lenses. I'm sure yes, because they have
Speaker 1: to be they have to be very careful. Um, if
Speaker 1: you're going to go for for lasic, for example, UM,
Speaker 1: your eyes have to fall within a certain set of
Speaker 1: parameters and they can treat myopia, hyperopia, and a stigmatism.
Speaker 1: But it has to be within a certain range. Now,
Speaker 1: of course that's measured in die opters. Um. That's that's
Speaker 1: kind of the degrees of prescription. So you know, if
Speaker 1: you hear someone say, oh, I've got minus three in
Speaker 1: this I and minus two point seven five in that,
Speaker 1: I the myopic. Yeah, their myopic. Yeah that a negative
Speaker 1: number means myopia, a positive number is hyperopia. And then um,
Speaker 1: a stigmatism can go either way. Yeah. Now, we we
Speaker 1: do have a great article on how lasic works on
Speaker 1: the website. Um and according to the research in there, UM,
Speaker 1: myopia treatable with lasic can be from negative zero point
Speaker 1: seven five to negative ten, which is that's a big,
Speaker 1: big range. And and I should also add that depending
Speaker 1: on which doctor you go to, they may tell you
Speaker 1: that if your eyesight falls within you know, a certain range,
Speaker 1: like saying, let's say the negative point seven five to
Speaker 1: say negative one point five. They might say, you know what,
Speaker 1: the the experience you're going to have, the the new
Speaker 1: vision you're going to have, is may not be so
Speaker 1: dramatic as to warrant laser eye surgery. Again, a reputable
Speaker 1: UH clinic is going to tell you if the the
Speaker 1: result is going to be truly noticeable or not. For
Speaker 1: some people, it may not be. I for at least
Speaker 1: years ago, when my wife could have done I was
Speaker 1: right there on the the border like like, you know,
Speaker 1: I could have gotten it done, but it may not
Speaker 1: have been that dramatic. And when you're talking about that
Speaker 1: kind of expense, really do you want to go in
Speaker 1: for that. My wife, however, she had gotten to the
Speaker 1: point of vision where they no longer use the eye chart.
Speaker 1: They would say how many fingers am I holding up?
Speaker 1: So she was an ideal candidate. Well you have to
Speaker 1: hold some up? Um? Yeah, whoa, you need some surgery.
Speaker 1: Hyperopia that they can treat with lacing ranges from plus
Speaker 1: zero point seven five to plus four and then they
Speaker 1: can treat a stigmatism for plus or minus zero point
Speaker 1: seven five to plus or minus four. Um. So that's
Speaker 1: a pretty a pretty decent range of vision that they
Speaker 1: can they can correct. Um. They also look at the
Speaker 1: cornea thickness. It has to be five microns or greater UM.
Speaker 1: That will explain why the cornea has to be at
Speaker 1: least that thick coming up. And that's going to be
Speaker 1: the the squiggly squirmy part where we're both like, okay,
Speaker 1: so here's what happens next. I'll be going out for water, Chris,
Speaker 1: Chris might Chris might go bye bye for about for
Speaker 1: about five minutes that thud. Yeah, But there are other
Speaker 1: types of laser eye surgery that you can pursue if
Speaker 1: your cornea is not of that thickness, if it's if
Speaker 1: it's thinner than that, there are other types of laser
Speaker 1: eye surgery you can look into, so to speak. Um.
Speaker 1: And then your pupil uh should be no more than
Speaker 1: six point five millimeters in diameter UM, although you know
Speaker 1: there are advances now that allow you to work with
Speaker 1: up to eight point five UM. Also, so if you've
Speaker 1: been Diesel from that that movie where he's got those
Speaker 1: huge corneas, the huge pupils, that just wouldn't work. Lady
Speaker 1: Gaga from that that one video, Yeah there you go. Yeah,
Speaker 1: those those folks, I'm sorry, or practically any Disney character,
Speaker 1: because I mean, have you seen Tangled. That girl's eyes
Speaker 1: are huge. Yeah, Sailor Moon's not gonna have it done either. Um.
Speaker 1: So yeah. And also if you're pregnant, have heart problems,
Speaker 1: severe heart problems anyway, Um, if you're taking drugs such
Speaker 1: as medicine for migraines or acne, um, you have a
Speaker 1: condition called kara to conas. I'm hoping I'm pronouncing it right.
Speaker 1: I didn't check the pronunciation, but that's a thinning of
Speaker 1: the cornea condition. And um, actually I might be Uh,
Speaker 1: I might not be eligible either because certain conditions like
Speaker 1: autoimmune diseases, one of which I have, UM, vascular disease,
Speaker 1: different kinds of eye diseases, and diabetes. All these things
Speaker 1: might prevent you from going through with a lasic procedure. Um.
Speaker 1: So these are things that the doctor is going to
Speaker 1: have to talk to you about. Um, and I would
Speaker 1: encourage history. Yeah. You need to be honest too, because
Speaker 1: you know, even though you may not want to wear glasses, uh,
Speaker 1: you know, this is serious business and you could end
Speaker 1: up with results that you are not happy with. It
Speaker 1: can be complications as well, I mean even yes, you know,
Speaker 1: it could be that everything goes well, but uh, you
Speaker 1: have some complications during the healing process, and if your
Speaker 1: medical history means that you can't have certain kinds of
Speaker 1: drugs to to help that healing process along, that could
Speaker 1: be an even bigger problem down the road. So yeah,
Speaker 1: it's very important. And then the actual exam, you're going
Speaker 1: to be looking through lots of different devices that are
Speaker 1: going to be measuring how your eyes are receiving light.
Speaker 1: And there's actually technically mapping out your eyes the inside
Speaker 1: of your eyes. Um. There's a thing called a corneal topographer. Yes,
Speaker 1: that's where they type on your eyes, right, that's a
Speaker 1: typograph back topographer. It actually maps the cornea, so it's
Speaker 1: it's looking at the actual shape and thickness of the cornea. Um,
Speaker 1: and it's too uh to really determine exactly how the
Speaker 1: light is behaving once it hits that part of your eye. Um.
Speaker 1: There's also the pupilometer, which is another device that's looking
Speaker 1: specifically at your pupil I mean there's not a big
Speaker 1: surprise there, right, you have a student in your eyeball. Yeah,
Speaker 1: and then the their software very powerful software, but working
Speaker 1: behind the scenes, that's mapping out your eye so that
Speaker 1: the surgeon is going to know exactly what sort of
Speaker 1: of adjustments they're going to need to make to your
Speaker 1: cornea in order for it to um to direct light
Speaker 1: the way you need it to be so that you
Speaker 1: don't have to wear glasses or contact lenses anymore. So
Speaker 1: it's it's pretty complex stuff. I mean, it's um pretty
Speaker 1: fascinating to see. And also a laser eye surgery procedure
Speaker 1: often requires two people, a surgeon and a patient, well
Speaker 1: beyond the patient to people to actually to do the procedure.
Speaker 1: The surgeon and then there's usually a an operator who's
Speaker 1: working on one of the laser machines. And so now
Speaker 1: we've now we've talked about the process where let's say
Speaker 1: that you've gone through you've had your eye exam, you've
Speaker 1: done your medical history, and they've determined your what is
Speaker 1: called an ideal candidate. Now that does not mean you
Speaker 1: are the perfect person to have had laser eye surgery.
Speaker 1: It just means that you fit those parameters that uh,
Speaker 1: you don't have anything outlying any of those parameters that
Speaker 1: would that would cause concern. It appears that it will
Speaker 1: work out. Yes, Uh, now is the time where you
Speaker 1: start to um to to actually go through the surgery itself.
Speaker 1: And I think I think we can walk through the
Speaker 1: laser process because that's still fairly common. I mean that's
Speaker 1: that's actually probably one of the most common forms of
Speaker 1: laser eye surgery out there. But we'll also talk about
Speaker 1: how the other kinds are a little different. So, um So, first,
Speaker 1: when you arrive to get your laser eye surgery done,
Speaker 1: one thing that's happens fairly frequently is that they offer
Speaker 1: you something to calm your nerves. Yes, because it turns
Speaker 1: out when a lot of people, when they're thinking they're
Speaker 1: going to be laying down on the table with someone
Speaker 1: shooting laser beams into their eyes, they get a little anxious.
Speaker 1: I can't imagine why. Actually, that's not the part that
Speaker 1: makes me anxious, but we'll get into that. Um So,
Speaker 1: you know it's the part immediately before the laser gets
Speaker 1: shut into your eye. That would be the part. Yeah,
Speaker 1: that's the part where it gets I'll score me so
Speaker 1: and yeah, I mean basically they're going to set up
Speaker 1: an appointment when you do your prep work. I don't
Speaker 1: think that they actually would take you back immediately and
Speaker 1: go all right, you look good, let's go. No, No,
Speaker 1: it's usually it's usually a day or two between. Speaking
Speaker 1: from my wife's experience, she went in and had the
Speaker 1: um the work that there up work done, and then
Speaker 1: it was a couple of days later after they had
Speaker 1: had a chance to really look at the data and
Speaker 1: they arranged for the time. And you also have to
Speaker 1: go there with someone else to drive you home. Yes,
Speaker 1: because you will not be able to use your eyeballs.
Speaker 1: Yeah for that. Yeah, because actually you're going to have
Speaker 1: some limited eyeball use ately afterwards. You can't put your
Speaker 1: weight on them. Yeah, exactly. Um, use some eye crutches,
Speaker 1: So I crunches. Um are those apple products? Um? No,
Speaker 1: it's not the lower case I E. I see. Um.
Speaker 1: So the next thing they're gonna do, once you're you're
Speaker 1: sure you want to go through this, of course, they
Speaker 1: also make you sign a waiver saying that you understand
Speaker 1: that there are things going on where they're gonna shoot
Speaker 1: lasers in your eyeballs and uh, there are risks involved
Speaker 1: with that, and part of this depends a lot on
Speaker 1: your cooperation, like still and and not running from the office. Screaming.
Speaker 1: Um again, I'm just imagining what would happen with me.
Speaker 1: They assuming your your nerves of steel are holding, are holding,
Speaker 1: they will go ahead and put some topical anesthetic in
Speaker 1: your eyes. Yes, so this is to numb your eyes
Speaker 1: because they will need to touch them and uh. And
Speaker 1: once you're once that started to take effect, you're lead
Speaker 1: into the operating room where you lay down on a table.
Speaker 1: It's usually a padded table and they position you so
Speaker 1: that you're going to be under the machine that goes
Speaker 1: ping and uh and and then they have to well,
Speaker 1: they have to secure your eyelids so that you're not
Speaker 1: going to be blinking. Yes, because you cannot blink, so
Speaker 1: they may be using usually a combination of things. There's
Speaker 1: usually some sort of tape that's safe to put on
Speaker 1: your your eyelids to keep your eyes open. There's also
Speaker 1: a device that will sit on top of the bottom
Speaker 1: part and top part of your eyelids to keep those
Speaker 1: them stationary. Um. This looks a lot like the device
Speaker 1: that was used in a famous documentary called a clockwork orange. Um. Yeah,
Speaker 1: it's a little freaky. If you're looking at someone who's
Speaker 1: getting this done. The eyelids speculum. Yeah. Yeah, it's to
Speaker 1: hold those eyelids in place, because of course, if you
Speaker 1: blink what the laser is going, it's gonna totally mess
Speaker 1: up the procedure. So they have to they have to
Speaker 1: stabilize and keep your eyelids from moving. Um and uh.
Speaker 1: They also put down a ring around your eye that
Speaker 1: that stops you from being able to move your eye around.
Speaker 1: You're you're looking directly up or directly straight straight ahead
Speaker 1: is the best way of putting it. Not up as
Speaker 1: in your eyes are turned up, but looking straightforward. It's
Speaker 1: just because you're laying on your back, it just happens
Speaker 1: to be up. And then as they the next step
Speaker 1: is the squigly part. Are you ready, Chris, Okay, So
Speaker 1: they pull out the microcra tome Yes, see they have to.
Speaker 1: They're gonna put some marks on your cornea to identify
Speaker 1: where it is, whether they're where they're going to use
Speaker 1: the microcarra tome um. Basically, when you're dealing with something
Speaker 1: as sensitive as vision, and you know, the professionals want
Speaker 1: to do a good job, they're going to want to
Speaker 1: be as accurate as possible, so they're going to mark
Speaker 1: your cornea to make sure that they use the microcarratone right,
Speaker 1: I don't even want to talk about it, Micart. What
Speaker 1: it was. It's a surgical instrument. Okay, It's a blade,
Speaker 1: a very thin blade, and this blade is used to
Speaker 1: cut a flap in your cornia, which is then pulled
Speaker 1: back so that the laser can shape the corn This
Speaker 1: is this is this is entertaining and painful to watch.
Speaker 1: This is the part that grosses me out. I'm sorry. Okay,
Speaker 1: So yeah, so there's actually this and this is lazing.
Speaker 1: There are other versions of laser ey surgery that do
Speaker 1: not use this, and some of them don't even use
Speaker 1: a microcarratone blade. They have a special laser that will
Speaker 1: cut this flap. But in lazing eye surgery, there is
Speaker 1: a flap that's cut and pulled back so that the
Speaker 1: laser can start to shape the cornea without that outer
Speaker 1: layer in place. And and so at this point, the
Speaker 1: the laser, which is um called an uh well it
Speaker 1: is an ex semer or x simer E x C
Speaker 1: I M E R. Actually did not look up the pronunciation.
Speaker 1: But this is the laser that does the actual shaping.
Speaker 1: It starts to vaporize parts of the cornea. And what's
Speaker 1: doing is it's shooting ultraviolet UH blasts and the lasers
Speaker 1: in the ultra violet lank range, which means you can't
Speaker 1: see it, right, it's outside the range of human sight UM.
Speaker 1: And what it's doing is is exciting uh the molecules
Speaker 1: in the cornea to the point where the molecular bonds
Speaker 1: break down. So it's actually that's what I talk about
Speaker 1: when vaporizing. It's not heating the eyeball up. Actually, a
Speaker 1: cool laser I expect you to break down. And when
Speaker 1: I mean cool laser, I don't mean that it's like
Speaker 1: super awesome, although it is. I mean it doesn't heat
Speaker 1: up the tissue. Now, remember earlier I mentioned that your
Speaker 1: cornea has to be five microns are greater when they
Speaker 1: start this procedure, and that's because when they're done using
Speaker 1: this laser, there has to be between two microns of
Speaker 1: thickness once they're done. Yeah, so there has to be
Speaker 1: enough for them to leave the proper amount once they're finished,
Speaker 1: otherwise you can't do this. So now, now using this
Speaker 1: laser to vaporize these molecular bonds and to reshape your cornea.
Speaker 1: That's essentially the same thing on on a grand concept
Speaker 1: level as grinding a glasses lens. So that's gonna been light.
Speaker 1: The way way it's the same thing is just we're
Speaker 1: using lasers and your actual eye to do it, which
Speaker 1: is pretty phenomenally awesome. It's also kind of scary. Um
Speaker 1: not at the end of it. After it might take
Speaker 1: I don't know, seventeen to twenty seconds to do this, Chris,
Speaker 1: because be okay, okay, yeah, per ie. Um. They then
Speaker 1: replace the flap back down on your eye and it heals.
Speaker 1: I mean, it sets down in place and is is
Speaker 1: healing as soon as it touches back down. That is
Speaker 1: one of the very cool things I think about that. Um.
Speaker 1: They the doctor will also probably put a little antibiotic
Speaker 1: on the flap just to make sure that there are
Speaker 1: no bacteria getting in there. Yeah, but but it maybe
Speaker 1: it starts to to heal, which is pretty phenomenal. Um.
Speaker 1: The the whole process only takes, like I said, about
Speaker 1: twenty seconds per eye. Uh and uh. Usually when you're
Speaker 1: down there, you'll hear people talk about how the doctor
Speaker 1: told him to look at, say like a blinking red light.
Speaker 1: That red light is not the laser. That's just a
Speaker 1: light that let's focus folk. Yeah, you're supposed to focus
Speaker 1: on that while this ultra violet laser is blast in
Speaker 1: your your cornea way. Um. And then once the flap
Speaker 1: comes down, you're usually you're given several different kinds of
Speaker 1: eye drops before you leave. Uh. There's a moisturizing eye drop,
Speaker 1: because after you get this process done, your eyes are
Speaker 1: gonna have a little bit of difficulty uh, generating the
Speaker 1: right kind of moisture to keep your eyes comfortable, so
Speaker 1: you're gonna have to actually endit. Eye drops in on
Speaker 1: a pretty regular basis. In fact, the first couple of days,
Speaker 1: it's it's like every hour you've got to add eye drops,
Speaker 1: and then as the time goes on, you have to
Speaker 1: use them less and less frequently. And my wife at
Speaker 1: this point rarely ever uses eye drops, but for the
Speaker 1: first year she was using them on on a fairly
Speaker 1: regular basis, although that that schedule changed over time, like
Speaker 1: after the first three months, it didn't need to be
Speaker 1: as frequent, um, and now it's it's rare when she
Speaker 1: needs them, but occasionally she does. Uh. And then you
Speaker 1: might also have antibotic eye drops that you might have
Speaker 1: to add every now and then. And some places apparently
Speaker 1: put give you a kind of gel that you put
Speaker 1: on the inside of your lower eyelids so that when
Speaker 1: you're asleep, it keeps your eye moisturized while you're sleeping.
Speaker 1: My wife, I don't remember her getting that, UM. I
Speaker 1: should have asked her before I left the house this morning,
Speaker 1: but I do not recall her getting that kind of stuff.
Speaker 1: I do remember the other kinds of eye drops though.
Speaker 1: And then they of course schedule, as you know, a
Speaker 1: lot of surgical procedures. UM. They also schedule regular appointments,
Speaker 1: even even as as soon as the next day, to
Speaker 1: make sure okay UM. And then gradually as time goes on, uh,
Speaker 1: you know, they check less frequently. You know, there'll be
Speaker 1: a year check up, but you know it's one day,
Speaker 1: and then they'll check the next week, the next month, UM,
Speaker 1: an increasing increasingly longer periods, just to make sure everything
Speaker 1: is healing the way it's supposed to, Just to make
Speaker 1: sure that there are um, that your eyes are doing
Speaker 1: what they're supposed to do when you're not suffering any
Speaker 1: ill effects from the surgery. Because in the case of
Speaker 1: I mean, there there are times when the flap can
Speaker 1: get a wrinkle in it. Yeah, I was wondering if
Speaker 1: we're going to get into that. Yeah, that can happens
Speaker 1: like that. That can cause a little bit of blurry
Speaker 1: vision and may require a second surgical procedure in order
Speaker 1: to get it straightened out, so so speak. Um. Also,
Speaker 1: you know there's a possibility that they may remove too
Speaker 1: little or too much of the corn. Yeah. Uh, yeah,
Speaker 1: they have to be That's why they have that's why
Speaker 1: they're doing that whole long pre ops sections so that
Speaker 1: they can determine that as precisely as possible to to
Speaker 1: reduce that risk as much as they can. And of course,
Speaker 1: again this also depends a lot on the patient. You
Speaker 1: have to be able to lay there and be still
Speaker 1: while your eye is being held open and lasers are
Speaker 1: being shot into it after someone's cut a flap in it.
Speaker 1: It's a little it's a bit of a challenge for
Speaker 1: some of us. Um. Let's talk really quickly about some
Speaker 1: of the other kinds of laser eye surgery besides lazing.
Speaker 1: The one of the the precursors to lazing, and it's
Speaker 1: still in use in a lot of places, is PRK
Speaker 1: laser ice surgery. Or photo refractive care TEC to me, Wow,
Speaker 1: I didn't know I was gonna be able to say that.
Speaker 1: In this one, they actually scrape away the outermost layer
Speaker 1: of the cornea with the laser and then reshape the
Speaker 1: tissue on the underlying surface of the cornea UM and
Speaker 1: then they have and then you have to allow the
Speaker 1: the protective layer that was scraped off to grow back,
Speaker 1: So there's actually a longer healing period with PRK than
Speaker 1: with lazing. They can use that process to h to
Speaker 1: work on near sidedness and a stigmatism at the same time, however,
Speaker 1: which is nice. Yep. And uh, then there's lazac with
Speaker 1: an e. The lasic we're talking about is with an eye,
Speaker 1: but LAZAC is a slightly more advanced version of PRK
Speaker 1: that uses um alcohol and solution to soften and then
Speaker 1: remove the epithelium, which is that protective layer, the almost
Speaker 1: layer of the cornea. Yeah, LASAC is laser epithelial curatatamliusis Yeah,
Speaker 1: I think I didn't mangle that terribly yep. And then
Speaker 1: there's epilasac, the modified version of that that uses a
Speaker 1: separator so that the because then in the traditional lazec
Speaker 1: you're actually removing the epithelium entirely, and epilasic you're creating
Speaker 1: a separator so that you preserve that epithelium and then
Speaker 1: replace it on the ice. So it's like you take
Speaker 1: the cover off, fiddle around a bit, and put the
Speaker 1: cover back on. It's probably a better eye surgeons out
Speaker 1: there just love me for saying that. Um. There's l
Speaker 1: t K or laser thermo keratoplasty. Uh. Now that it's
Speaker 1: used mainly for far sightedness and a stigmatism, and in
Speaker 1: this case they actually are using heat. They're using the
Speaker 1: heat of a laser beam to shrink and reshape the
Speaker 1: cornea rather than removing it, so they're actually reshaping it.
Speaker 1: They're pushing the stuff around as opposed to cutting it away. Um.
Speaker 1: And it's supposedly a much faster healing process than most
Speaker 1: other kinds of corrective surgery, and it's generally considered to
Speaker 1: be less invasive. So it's uh, that's an interesting approach.
Speaker 1: There's also there's a custom view lazic, conventional intra lazic,
Speaker 1: custom view intra lazic. These are all variations on the
Speaker 1: basic lasic approach. Basic LAZIC, and there are of course
Speaker 1: complications with some of these. We mentioned some before. I've
Speaker 1: I've known people to undergo LASIC and complain of some
Speaker 1: problems with night vision where they see halos. There's a
Speaker 1: lot of that where everyone looks like master chief no. Um.
Speaker 1: Basically when you look at a light source, it looks
Speaker 1: like it has shimmering circle around it. Yeah. Yeah, especially
Speaker 1: things for like if you're driving at night and you'll
Speaker 1: know no halos around headlights, things like that. Or you're
Speaker 1: sensitive to bright light. Yeah, yeah, you're light sensitivity. Especially
Speaker 1: for the first few days, it's probably gonna be a little, uh,
Speaker 1: a little rough. But for some people it just it
Speaker 1: stays that way. So like my wife, she wears sunglasses
Speaker 1: a lot more frequently than she used to. And uh
Speaker 1: for for some people too, I've heard that in some cases, uh,
Speaker 1: it is possible for your eyes basically to slowly regress
Speaker 1: to where they were before. Um. I don't know exactly
Speaker 1: why that is. You know, I have read report works
Speaker 1: that that it happens. Um. But and you know, some
Speaker 1: people who have and you know, enjoyed the benefits of
Speaker 1: the surgery for years. And then there are others who
Speaker 1: gradually returned to uh to the way they were before.
Speaker 1: I'm sure that it probably since since part of the
Speaker 1: cornea has been removed, I would imagine that it's probably
Speaker 1: not as uh drastic change so it was. But I've
Speaker 1: I've read that that that can happen. I would imagine
Speaker 1: if you have some sort of condition that continues to
Speaker 1: change the shape of your eyeball, that would be it
Speaker 1: would be a big problem because the focal point would
Speaker 1: constantly be changing then or gradually be changing. Yes, well,
Speaker 1: I think that wraps up this discussion about laser eye surgery,
Speaker 1: which I was it was interesting. I mean, it's an
Speaker 1: interesting concept. It's also I agree it's a little square mey.
Speaker 1: You know, they're I don't like the whole idea of
Speaker 1: people messing with my balls. Well, not a lot of
Speaker 1: people are fall into that category, and it's not just us, um,
Speaker 1: But for the most part, I have heard very positive
Speaker 1: things about these eye surgeries. And you know, if it's
Speaker 1: something that sounds sounds good to you, now you know
Speaker 1: a little bit more about how it works. Um. And
Speaker 1: here's the other thing that's kind of cool. Again, if
Speaker 1: you go to a reputable clinic, they're going to actually
Speaker 1: explain how this works to you in very simple terms,
Speaker 1: because they want to make sure that you know. Part
Speaker 1: of being an ideal candidate is being the kind of
Speaker 1: candidate is not going to freak out when you're on
Speaker 1: the table that rules me out, darn to al Right, guys, Well,
Speaker 1: if you have any uh anything you would like us
Speaker 1: to talk about, any topics you think it would be
Speaker 1: particularly interesting, you can let us know. Shoot us an
Speaker 1: email that addresses tech stuff at how stuff Works dot com,
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Speaker 1: are handled, there is tech stuff H s W and
Speaker 1: Chris and I will talk to you again really soon.
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