Speaker 1: Get in touch with technology with tech Stuff from how
Speaker 1: stuff works dot com. Hey there, and welcome to tech Stuff.
Speaker 1: I'm your host, Jonathan Strickling. I'm an executive producer with
Speaker 1: How Stuff Works in love all things tech, and when
Speaker 1: my producer is not being super snarky at me, I
Speaker 1: like to go back and reflect on the past. So
Speaker 1: I very rarely get to do it because Tar's got
Speaker 1: some attitude on her. Let me tell you, but today
Speaker 1: it's time for another classic episode of tech Stuff, which
Speaker 1: means it's Friday. Today. We're gonna look at an episode
Speaker 1: that originally published on October twenty four, two thousand eleven.
Speaker 1: Chris Pallette and I talked about laser eye surgery. I
Speaker 1: found it fascinating. Chris turned about eighteen shades of green
Speaker 1: while we recorded this. It's been a long time since
Speaker 1: I've seen Mr Pillette, but I remember how green he
Speaker 1: turned when we talked about the process. I have had
Speaker 1: laser eye surgery done, and now I'm essentially a super human.
Speaker 1: I can see through walls and shoot lasers with my eyes. Maybe,
Speaker 1: I guess we'll find out. Let's listen in on this
Speaker 1: classic episode today. We're going to talk about laser eye surgery.
Speaker 1: We've had some people ask us about laser eye surgery
Speaker 1: and what goes into it and exactly how are lasers
Speaker 1: used in the process. But I think that's a record
Speaker 1: for your use of that version of lasers. Yeah, And
Speaker 1: so we're going to, uh, we're gonna kind of break
Speaker 1: it down and talk about what goes into a laser
Speaker 1: eye surgery procedure. And we should also mention I should
Speaker 1: mention that I am very close to someone who has
Speaker 1: had laser eye surgery, not right now, not like physically.
Speaker 1: I was going to my wife. My wife had laser
Speaker 1: eye surgery, um, and she has been very happily moving
Speaker 1: around without the need for glasses for several years now, um.
Speaker 1: And it was very impressive to me because my wife
Speaker 1: is not the the person who typically likes people, uh,
Speaker 1: you know, messing with eyeballs exactly. Yeah, She's it's not
Speaker 1: high on our list of things to do today, but
Speaker 1: she did it anyway. And we're going to kind of
Speaker 1: talk about the process and what you have to do
Speaker 1: in order to get laser eye surgery and what's actually
Speaker 1: being done to you. Yeah. And I think probably the
Speaker 1: best place to start is speaking of eyeballs with the
Speaker 1: eyeball itself. Yeah, and why you might need laser eye
Speaker 1: surgery in the first place. Right, Uh, to to to
Speaker 1: understand this discussion, you have to have at least a
Speaker 1: basic geography of the eyeball. So let's talk a little
Speaker 1: bit about the eye. So, so your your eye. The
Speaker 1: outer coating is this sort of tough outer coating called
Speaker 1: the sclera, and that's sort of what keeps the eyeball
Speaker 1: in its shape. It's it's kind of the the well,
Speaker 1: it's just it's the outer layer. And then part of
Speaker 1: this outer layer, about I think one sixth of it
Speaker 1: is the cornea, which is the clear outer layer that
Speaker 1: goes or the part of your eye where light actually
Speaker 1: passes through to get to you know, your eyeball. Right,
Speaker 1: So the cornea is, uh, it's kind of like a
Speaker 1: window in a way, or if you want to think
Speaker 1: of it like a a tablet device or something. It's
Speaker 1: the gorilla glass. It's on the outside that protects the
Speaker 1: the the innards. And then behind the cornea, well, first
Speaker 1: of all, you've got this sort of a watery clear
Speaker 1: liquid called the aqueous humor. Yeah, this goes back to
Speaker 1: the old humors. UH idea that dates back centuries where
Speaker 1: we used to think that our bodies we were like
Speaker 1: we're governed by a well, a small group of various
Speaker 1: liquids called humors. We've somewhat developed beyond that at this point,
Speaker 1: although I do think it's it's funny that even now
Speaker 1: we are referring to this particular liquid as a humor. Yes,
Speaker 1: so so the queens humor. It's it's this clear, clear
Speaker 1: liquid that's behind the cornea. It's also in front of
Speaker 1: the iris, and there's a little bit behind the iris
Speaker 1: as well. So then that leads to the question, what
Speaker 1: then is the iris. Well, that's the that's the color
Speaker 1: part of your eye. So for example, my iris is
Speaker 1: blue because it lacks a certain amount of pigmentation which
Speaker 1: makes it a blue color. My wife's eyes are brown.
Speaker 1: And uh, this is the part of the other acts
Speaker 1: is like an adjustable diaphragm around the pupil. So the
Speaker 1: pupil is the 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 gets 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 us into 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 gonna allow more of the pupil to be exposed
Speaker 1: so that you get more light so that you can
Speaker 1: maneuver through because you know you're gonna be able to
Speaker 1: you need to be able to see if you're in
Speaker 1: a really bright environment. In order to protect the eye,
Speaker 1: the diaphragm is gonna close around the pupil to restrict
Speaker 1: the 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. Sure, 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 sensor 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
Speaker 1: lens right behind the pupil, 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,
Speaker 1: UM he sells sense the presence of light and UH
Speaker 1: through a chemical reactions send that information to your brain
Speaker 1: and then your brain says, hey, I recognize that that's
Speaker 1: a puppy. Also, at the interesting point, if you weren't
Speaker 1: familiar with us, UH, the image that you see when
Speaker 1: you're looking at something. When it hits your retina, it's
Speaker 1: actually inverted, just as it is in a camera. But yes,
Speaker 1: that's the So this, this is the basic part of
Speaker 1: the eye. Now, what happens when something is just not
Speaker 1: quite right? For example, Uh, Chris, I don't know, are
Speaker 1: you near sighted or far sighted? I am myopic. I
Speaker 1: am also myopic. That means we are both near sighted,
Speaker 1: and since we both have our our glasses off at
Speaker 1: the moment, we're both a little blurry. So myopia means
Speaker 1: that the focal point is hitting. Uh, it's it's hitting
Speaker 1: before it gets to your retina. So inside your eye
Speaker 1: there's a you know, the light is being directed by
Speaker 1: the lens to your retina. Uh, those the points of
Speaker 1: light are all converging, right, and that point of convergence
Speaker 1: is the focal point. Now, the focal point for those
Speaker 1: with myopia is in front of the retina. It's not
Speaker 1: hitting the retina just right. So that means that when
Speaker 1: we start looking around things, things tend to be the
Speaker 1: further way things are, the blurrier they tend to be. Yes. Um, Now,
Speaker 1: this can happen through various uh, just well irregularities. There
Speaker 1: could be irregularities in the cornea that can cause this
Speaker 1: to happen, or in the lens itself, or it could
Speaker 1: be that the eyeball itself is elongated. Yes, so that
Speaker 1: the you know, if the eyeball was not elongated, the
Speaker 1: focal point would be right there on the retina where
Speaker 1: it's supposed to be and everything will be fine, but
Speaker 1: the eyeball has been stretched. Nice sound effect. Thank you
Speaker 1: doesn't necessarily doesn't necessarily mean that someone's actually gone in
Speaker 1: there and stretch your eyeball. It just means that that's
Speaker 1: kind of the way it developed. Um now far sighting
Speaker 1: this which is a hyperopia hyperopia, thank you, I'm glad
Speaker 1: you're ready for that one. Ready, Yeah, hyperopia. You've got
Speaker 1: the focal point that's that's actually behind the retina, so
Speaker 1: when the lights hitting hitting the retina, it's not converged
Speaker 1: on that point like it should be. And U 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: the 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 well know I'm saying, are you and have an astigmatism?
Speaker 1: Me too? Me too? Just it happens to 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. Yeah. Um, And so basically that sort
Speaker 1: of confuses the way the light is travel 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: a stigmatism on top of another eye condition. Yes. Yeah,
Speaker 1: it's really an uneven curvature of the cornea or or lens.
Speaker 1: And yeah, it's it. It can cause problems. So the
Speaker 1: thing is that the humans are clever and um, 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 can direct
Speaker 1: light so that it corrects for these problems. I can't
Speaker 1: imagine the amount of trial and error it took to
Speaker 1: be able to figure this out. But to correct your
Speaker 1: your vision you have to, you know, take into account
Speaker 1: 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: and hyperopia. But anyway, the curvature of the lens depends
Speaker 1: upon the condition, right, you know, if it's gonna be
Speaker 1: a concave lens for one and a convex lens for
Speaker 1: the other, And honestly, I can't remember the one from
Speaker 1: the other. I guess I could stare at my glasses
Speaker 1: long enough and try and figure it out. But um,
Speaker 1: but the point being that that's what's going to direct
Speaker 1: the light the right way into your eye so that
Speaker 1: it corrects for whatever problem you already have. Chris and
Speaker 1: I have more to say about laser eye surgery, but
Speaker 1: first let's take a quick break to thank our sponsor.
Speaker 1: What if we didn't want to wear glasses, what if
Speaker 1: we wanted something where it wasn't you know this this
Speaker 1: pair of frames sitting on our face. Well that's when
Speaker 1: we started to come up, well, we could maybe make
Speaker 1: a lens that could sit directly on the eye and
Speaker 1: do the same sort of correction. It's gonna require a
Speaker 1: more precise approach because it's going to be a much
Speaker 1: smaller lens that by definition, I mean, you can't have
Speaker 1: an enormous lens shoved into your eye and expect any
Speaker 1: sort of comfort. So, um, well that's where the contact
Speaker 1: lens idea came from, where we started to kind of
Speaker 1: get you you apply these same kinds of thought to
Speaker 1: a thin lens that could fit directly on top of
Speaker 1: the eye. But then we thought, hey, wait a minute,
Speaker 1: we're really just talking about lenses here. Even even the
Speaker 1: cornea can act somewhat as a lens. The cornea on
Speaker 1: your eye itself directs light. So what if we were
Speaker 1: to reshape the cornia so that it corrected for whatever
Speaker 1: problems we had as you know, as far as vision
Speaker 1: problems are concerned. Uh, what if we just did that,
Speaker 1: then we wouldn't have to wear contact lenses or glasses
Speaker 1: or anything. And that's where the idea for corrective surgery
Speaker 1: comes from. And um, and at its very most basic level,
Speaker 1: what correct to what this laser eye surgery is doing
Speaker 1: is it's altering the shape of the cornea so that
Speaker 1: directs light in a way that corrects for whatever vision
Speaker 1: problem you have. That's that's the basic you know, when
Speaker 1: you get down to it, that's what laser eye surgery
Speaker 1: is all about. So it's just it's that same principle
Speaker 1: behind grinding the lens so that you can see, you know,
Speaker 1: in a pair of eyeglasses, but now it's applied directly
Speaker 1: to our biology. It sadly does not mean you will
Speaker 1: actually end up with laser shooting out of your eyes,
Speaker 1: well at least not for most people. No, I would
Speaker 1: think that's a pretty rare side effect. So, yeah, where
Speaker 1: 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 a laser eye surgery session. Yeah,
Speaker 1: because frankly, it's it's reminds me of a lot of
Speaker 1: life events. You know. The actual event itself doesn't really
Speaker 1: take all that long. Laser eye surgery only takes a
Speaker 1: few minutes. Yeah, it can take less than half an
Speaker 1: hour total um. But there is quite a bit of
Speaker 1: preparation that needs that you need to go through beforehand.
Speaker 1: To make sure that everything goes smoothly, um and preferably
Speaker 1: not panicky, which is the reason that I haven't had
Speaker 1: it done. Yeah, So the first thing you have to
Speaker 1: do is you have to go through and we're talking
Speaker 1: about a reputable laser eye surgeon. This is a good
Speaker 1: time for us to point out there are a lot
Speaker 1: of different facilities out there that offer laser eye surgery services.
Speaker 1: Do your research. Yes, that's a great idea, because I
Speaker 1: know for a fact that there are there's a few
Speaker 1: in Atlanta that have a reputation for being less than honesty,
Speaker 1: Like they'll the what the they do is they'll offer
Speaker 1: this amazing sounding deal and of course we all know
Speaker 1: the phrase it sounds too good to be true. It
Speaker 1: was probably on the internet. Um, and the deal the
Speaker 1: deal would be something like two D and I, which
Speaker 1: is about a tenth of what some eye surgeries cost,
Speaker 1: you know, and you're thinking, Wow, that's amazing, And then
Speaker 1: you know it's got an official sounding name and that's
Speaker 1: gonna be great. And then if you actually start doing
Speaker 1: some research, you'll see that there's often a lot of
Speaker 1: bait and switch involved where you'll go in and they'll
Speaker 1: 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 hundred
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 quick alert. So assuming that the the
Speaker 1: 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 thorough 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 parameters,
Speaker 1: and they can treat myopia, hyperopia and a stigmatism, but
Speaker 1: it has to be within a certain range. Now, of
Speaker 1: course that's measured in diopters um. That's that's kind of
Speaker 1: the degrees of prescription. So you know, if you hear
Speaker 1: someone say, oh, I've got minus three in this I
Speaker 1: and minus two point seven five in that I the myopic. Yeah,
Speaker 1: their myopic. Yeah that a negative number means myopia, a
Speaker 1: positive number is hyperopia. And then um, a stigmatism can
Speaker 1: go either way. Yeah. Now, we we do have a
Speaker 1: great article on how lasic works on the website. UM
Speaker 1: and according to the research in there, UM, myopia treatable
Speaker 1: with lasic can be from negative zero point seven five
Speaker 1: to negative ten, which is that's a big, big range.
Speaker 1: And and I should also add that depending on which
Speaker 1: doctor you go to, they may tell you that if
Speaker 1: your eyesight falls within you know, a certain range, like saying,
Speaker 1: let's say the negative point seven five to say negative
Speaker 1: one point five, they might say, you know what, the
Speaker 1: the experience you're going to have, the the new vision
Speaker 1: you're going to have, may not be so dramatic as
Speaker 1: to warrant laser eye surgery. Again, a reputable UH clinic
Speaker 1: is going to tell you if the the result is
Speaker 1: going to be truly noticeable or not. For some people
Speaker 1: it may not be. I for at least years ago,
Speaker 1: when my wife could have done I was right there
Speaker 1: on the the border like like you know, I could
Speaker 1: have gone it done, but it may not have been
Speaker 1: that dramatic. And when you're talking about that kind of expense,
Speaker 1: really do you want to go in for that. My wife, however,
Speaker 1: she had gotten to the point of vision where they
Speaker 1: no longer use the eye chart. They would say how
Speaker 1: many fingers am I holding up? So she was an
Speaker 1: ideal candidate. Well, you have to hold some up. Um,
Speaker 1: Like whoa, you need some surgery. Hyperopia that they can
Speaker 1: treat with lace ranges from plus zero point seven five
Speaker 1: to plus four and then they can treat a stigmatism
Speaker 1: for plus or minus zero point seven five to plus
Speaker 1: or minus four um. So that's a pretty a pretty
Speaker 1: decent range of vision that they can they can correct. Um.
Speaker 1: They also look at the cornea thickness. It has to
Speaker 1: be five microns or greater um. That's we'll explain why
Speaker 1: the cornea has to be at least that thick coming up.
Speaker 1: And that's going to be the the squiggly squirmy part
Speaker 1: where we're both like, okay, so here's what happens next.
Speaker 1: I'll be going out for some water, Chris, Chris might
Speaker 1: might go bye bye for about for about five minutes.
Speaker 1: Was that thud? Yeah? But there are other types of
Speaker 1: laser eye surgery that you can pursue if your cornea
Speaker 1: is not of that thickness, if it's if it's thinner
Speaker 1: than that, there are other types of laser eye surgery
Speaker 1: you can look into, so to speak, right, Um. And
Speaker 1: then your pupil uh should be no more than six
Speaker 1: point five millimeters in diameter. Um, although you know there
Speaker 1: are advances now that allow you to work with up
Speaker 1: to eight point five um. Also, so if you' have
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 is not gonna have it
Speaker 1: done either. Um. So yeah. And also if you're pregnant,
Speaker 1: have heart problems, severe heart problems anyway, Um, if you're
Speaker 1: taking drugs such as medicine for migraines or acne, um,
Speaker 1: you have a condition called kara to countess, I'm hoping
Speaker 1: I'm pronouncing it right. I didn't check the pronunciation, but
Speaker 1: it's a thinning of the cornea condition. And UM, actually
Speaker 1: I might be Uh, I might not be eligible either
Speaker 1: because certain conditions like autoimmune diseases one of which I have, UM,
Speaker 1: vascular disease, different kinds of eye diseases, and diabetes, all
Speaker 1: these things might prevent you from going through with a
Speaker 1: lasic procedure. UM. So these are things that the doctor
Speaker 1: is going to have to talk to you about. UM,
Speaker 1: and I would encourage history. Yeah, you need to be
Speaker 1: honest too, because you know, even though you may not
Speaker 1: want to wear glasses. Uh, you know, this is serious
Speaker 1: business and you could end up with results that you
Speaker 1: are not happy with. It can be complications as well.
Speaker 1: I mean even yes, you know, it could be that
Speaker 1: everything goes well, but uh, you have some complications during
Speaker 1: the healing process. And if your medical history means that
Speaker 1: you can't have certain kinds of drugs to to help
Speaker 1: that healing process along, that could be an even bigger
Speaker 1: problem down the road. So yeah, it's very important. And
Speaker 1: then the actual exam, you're going to be looking through
Speaker 1: lots of different devices that are going to be measuring
Speaker 1: how your eyes are receiving light. And there's actually technically
Speaker 1: mapping out your eyes, the inside of your eyes. Um,
Speaker 1: there's a thing called a corneal topographer. Yes, that's where
Speaker 1: they type on your eyes, right, that's a typographer topographer.
Speaker 1: It actually maps the cornea, so it's it's looking at
Speaker 1: the actual shape and thickness of the cornea. Um, and
Speaker 1: it's to uh to really determine exactly how the light
Speaker 1: 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 eye,
Speaker 1: all yeah, and then the their software, very powerful software,
Speaker 1: but working behind the scenes that's mapping out your eye
Speaker 1: so that the surgeon is going to know exactly what
Speaker 1: sort of of adjustments they're going to need to make
Speaker 1: to your cornea in order for it to um to
Speaker 1: direct light the way you need it to be so
Speaker 1: that you don't have to wear glasses or contact lenses anymore.
Speaker 1: So it's it's pretty complex stuff. I mean, it's um,
Speaker 1: pretty fascinating to see. And also a laser eye surgery
Speaker 1: procedure often requires two people A surgeon and at well
Speaker 1: beyond the patient to people to actually to do the
Speaker 1: procedure the surgeon, and then there's usually a an operator
Speaker 1: who's working on one of the laser machines. I hate
Speaker 1: to interrupt while we're strolling down memory lane, but it's
Speaker 1: time for us to take another quick break to think
Speaker 1: our sponsor. Now we've talked about the process where let's
Speaker 1: say that you've gone through you've had your eye exam,
Speaker 1: you've done your medical history, and they've determined your what
Speaker 1: is called an ideal candidate. Now, that does not mean
Speaker 1: you are the perfect person to have had laser eye surgery.
Speaker 1: It just means that you fit those parameters that um
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,
Speaker 1: first when you arrive to get your laser eye surgery done,
Speaker 1: one thing that 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 at UM. So
Speaker 1: you know, it's the part immediately before the laser gets
Speaker 1: shut to your eye. That would be the part. Yeah,
Speaker 1: that's the part where it gets I'll score me. Yeah,
Speaker 1: so and yeah. I mean basically, they're going to set
Speaker 1: up an appointment when you do your your pre op work.
Speaker 1: I don't think that they actually would take you back
Speaker 1: immediately and 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 the pre up work done, and
Speaker 1: then it was a couple of days later after they
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, exactly, You're you're going to have
Speaker 1: some limited eyeball use immediately afterwards. You can't put your
Speaker 1: weight on them exactly. Um, use some eye crutches. So
Speaker 1: I crutches? Um are those apple products? Um? No, it's
Speaker 1: not the lower case I E I see. Um. So
Speaker 1: the next thing they're gonna do, once you're you're sure
Speaker 1: you want to go through this, of course, they also
Speaker 1: make you sign a waiver saying that you understand that
Speaker 1: there are things going on where they're gonna shoot lasers
Speaker 1: in your eyeballs and uh, there are risks involved with that,
Speaker 1: and part of this depends a lot on your cooperation,
Speaker 1: like and and not running from the office screaming. Um again,
Speaker 1: I'm just imagining what would happened with me. They assuming
Speaker 1: your your nerves of steel are holding, are holding, they
Speaker 1: will go ahead and put some topical anesthetic in your eyes. Yes,
Speaker 1: so this is to numb your eyes because they will
Speaker 1: need to touch them and uh. And once you're once
Speaker 1: that started to take effect, you're lead into the upberating
Speaker 1: room where you laid down on a table. It's usually
Speaker 1: a padded table, and they position you so that you're
Speaker 1: going to be under the machine that goes ping and
Speaker 1: uh and and then they have to h while they
Speaker 1: have to secure your eyelids so that you're not going
Speaker 1: to be blinking, yes, because you cannot blink, so they
Speaker 1: may be using usually a combination of things. There's usually
Speaker 1: some sort of tape that's safe to put on your
Speaker 1: your eyelids to keep your eyes open. There's also a
Speaker 1: device that will sit on top of the bottom part
Speaker 1: and top part of your eyelids to keep those them stationary. Um.
Speaker 1: This looks a lot like the device that was used
Speaker 1: 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 when the laser is going, it's gonna totally mess
Speaker 1: up the procedure. So they have to they have to
Speaker 1: uh stabilize and and keep your eyelids from moving. Um.
Speaker 1: And they also put down a ring around your eye
Speaker 1: that that stops you from being able to move your
Speaker 1: eye around. You're you're looking directly up. Are directly straight
Speaker 1: straight ahead is the best way of putting it. Not
Speaker 1: up as in your eyes are turned up, but looking straightforward.
Speaker 1: It's just because you're laying on your back. It just
Speaker 1: happens to be up. And then as they the next
Speaker 1: step is the squiggly part. Are you ready? Okay, So
Speaker 1: they pull out the microcarra tome Yes, see they have to.
Speaker 1: They're gonna put some marks on your cornea to identify
Speaker 1: where it is green, where they're where they're going to
Speaker 1: use the microcarra tome um. Basically, when you're dealing with
Speaker 1: something as sensitive as vision, and you know, the professionals
Speaker 1: want to do a good job, they're going to want
Speaker 1: to be as accurate as possible, so they're going to
Speaker 1: mark your cornea to make sure that they use the
Speaker 1: microcarratone right, I don't even want to talk about it. Microcart.
Speaker 1: It's a surgical instrument, okay. It's a blade, a very
Speaker 1: thin blade, and this blade is used to cut a
Speaker 1: flap in your cornia, which is then pulled back so
Speaker 1: that the laser gets shaped corny. This is this is
Speaker 1: this is entertaining and painful to watch. This is the
Speaker 1: part the grosses me out. I'm sorry. Okay, So yeah,
Speaker 1: so there's actually this and this is lazing. There are
Speaker 1: other versions of laser eye surgery that do not use this,
Speaker 1: and some of them don't even use a microcarratone blade.
Speaker 1: They have a special laser that will cut this flap.
Speaker 1: But an end lazing eye surgery, there is a flap
Speaker 1: that's cut and pulled back so that the laser can
Speaker 1: start to shape the cornia without that outer layer in place.
Speaker 1: And UM. And so at this point, the laser, which
Speaker 1: is um called an well it's an ex semer or
Speaker 1: x simer E x c I M E R I
Speaker 1: actually did not look up the pronunciation. But this is
Speaker 1: the laser that does the actual shaping. It starts to
Speaker 1: vaporize parts of the cornea. And what's doing is it's
Speaker 1: shooting ultraviolet UH blasts and the lasers in the ultraviolet
Speaker 1: lank range, which means you can't see it right, it's
Speaker 1: outside the range of human sight. UM. And what it's
Speaker 1: doing is it's exciting UH the molecules in the cornea
Speaker 1: to the point where the molecular bonds breakdown. So it's
Speaker 1: actually that's what I talk about when vaporizing. It's not
Speaker 1: heating the eyeball up, especially a cool laser. I expect
Speaker 1: you to break down. And when I mean cool laser,
Speaker 1: I don't mean that it's like super awesome, although it is.
Speaker 1: I mean it doesn't heat up the tissue. Now, remember
Speaker 1: earlier I mentioned that your cornea has to be five
Speaker 1: microns are greater when they start this procedure, and that's
Speaker 1: because when they're done using this laser, there has to
Speaker 1: be between two three microns of thickness once they're done. Yeah,
Speaker 1: so there has to be enough for them to leave
Speaker 1: the proper amount once they're finished, otherwise you can't do this.
Speaker 1: So now, now using this laser to vaporize these molecular
Speaker 1: bonds and to reshape your cornea, that's essentially the same
Speaker 1: thing on on a grand concept level as grinding a
Speaker 1: glasses lens. So that's gonna been light the way way.
Speaker 1: It's the same things, just we're using lasers and your
Speaker 1: actual eye to do it, which is pretty phenomenally awesome.
Speaker 1: It's also kind of scary um not at the end
Speaker 1: of it. After it might take I don't know seventeen
Speaker 1: to twenty seconds to do this. Chris's be okay, okay, yeah,
Speaker 1: per i. Um. They then replace the flap back down
Speaker 1: on your eye and it heals. I mean, it sets
Speaker 1: down in place and is is healing as soon as
Speaker 1: it touches back down. That is one of the very
Speaker 1: cool things I think about that. Um. They the doctor
Speaker 1: will also probably put a little antibiotic on the flap
Speaker 1: just to make sure that there are no bacteria getting
Speaker 1: in there. Yeah, but but it maybe it starts to heal,
Speaker 1: which is pretty phenomenal. Um. The the whole process only takes,
Speaker 1: like I said, about twenty seconds per eye. Uh. And uh,
Speaker 1: usually when you're down there, you'll hear people talk about
Speaker 1: how the doctor told him to look at, say like
Speaker 1: a blinking red light. That red light is not the laser.
Speaker 1: That's just a light that let's Yeah, you're supposed to
Speaker 1: focus on that while this ultra violet laser is blasting
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 before you leave. Uh, there's a moisturizing
Speaker 1: eye drop because after you get this process done, your
Speaker 1: eyes are gonna have a little bit of difficulty, uh,
Speaker 1: generating the right kind of moisture to keep your eyes comfortable,
Speaker 1: so you're gonna have to actually add eye drops in
Speaker 1: on a pre regular basis. In fact, the first couple
Speaker 1: of days, it's it's like every hour you've got to
Speaker 1: add eye drops, and then as the time goes on,
Speaker 1: you have to use them less and less frequently. And
Speaker 1: my wife at this point rarely ever uses eye drops.
Speaker 1: But for the first year she was using them on
Speaker 1: on a fairly regular basis, although that that schedule changed
Speaker 1: over time, like after the first three months, it didn't
Speaker 1: need to be as frequent. Um. And now it's it's
Speaker 1: rare when she needs them, but occasionally she does. Uh.
Speaker 1: And then you might also have antibotic eye drops that
Speaker 1: you might have to add every now and then. And
Speaker 1: some places apparently put give you a kind of gel
Speaker 1: that you put on the inside of your lower eyelids
Speaker 1: so that when you're asleep, it keeps your eye moisturized
Speaker 1: while you're sleeping. My wife, I don't remember her getting that. UM.
Speaker 1: I should have asked her before I left the house
Speaker 1: this morning, but I do not recall her getting that
Speaker 1: kind of stuff. I do remember the other kinds of
Speaker 1: eye drops though. And then they of course schedule, as
Speaker 1: you know, a lot of surgical procedures. UM. They also
Speaker 1: schedule regular appointments, even even as as soon as the
Speaker 1: next day, to make sure okay, UM. And then gradually
Speaker 1: as time goes on, uh, you know, they check less frequently.
Speaker 1: You know, there'll be a year check up, but you
Speaker 1: know it's one day, and then they'll check the next
Speaker 1: week and the next month, UM an increasing increasingly longer periods,
Speaker 1: just to make sure everything is healing the way it's
Speaker 1: supposed to. Just to make sure that there are um,
Speaker 1: that your eyes are doing what they're supposed to do,
Speaker 1: when you're not suffering any ill effects from the surgery.
Speaker 1: Because in the case of I mean there there are
Speaker 1: times when the flap can get a wrinkle in it. Yeah,
Speaker 1: I was wondering if we're going to get into that. Yeah,
Speaker 1: that can have things like that that can cause a
Speaker 1: little bit of blurry vision and may require a second
Speaker 1: surgical procedure in order to get it straightened out, so
Speaker 1: you speak. UM. Also, you know, there's a possibility that
Speaker 1: they may remove too little or too much of the
Speaker 1: cornea UM. So they have to be. Yeah, they have
Speaker 1: to be. That's why they that's why they're doing that
Speaker 1: whole long pre ops sections, so that they can determine
Speaker 1: that as precisely as possible to to reduce that risk
Speaker 1: as much as they can. And of course, again this
Speaker 1: also depends a lot on the patient. You have to
Speaker 1: be able to lay there and be still while your
Speaker 1: eye is being held open and lasers are being shot
Speaker 1: into it after someone's kind of flapping it. It's a
Speaker 1: little it's a bit of a challenge for some of us.
Speaker 1: Um let's talk really quickly about some of the other
Speaker 1: kinds of laser ice surgery besides lazing. The one of
Speaker 1: the the precursors to lazing, and it's still in use
Speaker 1: in a lot of places is PRK laser ice surgery
Speaker 1: or photo refractive care TECTO me. Oh, I didn't know
Speaker 1: I was gonna be able to say that. In this one,
Speaker 1: they actually scrape away the outermost layer of the cornea
Speaker 1: with the laser and then reshape the tissue on the
Speaker 1: underlying surface of the cornea um and then they have
Speaker 1: and then you have to allow the the protective layer
Speaker 1: that was scraped off to grow back, so there's actually
Speaker 1: a longer healing period with PRK than with laze. They
Speaker 1: can use that process to uh to work on near
Speaker 1: sidedness and a stigmatism at the same time, however, which
Speaker 1: is nice. Yep. And uh. Then there's lazac with an E.
Speaker 1: The lasic we're talking about is with an eye, but
Speaker 1: lazac is a slightly more advanced version of PRK that
Speaker 1: uses um alcohol and solution to soften and then remove
Speaker 1: the epithelium, which is that protective layer, that almost layer
Speaker 1: of the cornium. Yeah, lasac is a laser epithelial caratatamliusis 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 laze
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 bet the eye surgeons
Speaker 1: out there just love me for saying that um there's
Speaker 1: l t K or laser thermo keratoplasty. Uh No. 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 lazic approach basic lazing, 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. Basically,
Speaker 1: when you look at a light source, it looks like
Speaker 1: it has shimmering circle around it. Yeah. Yeah, especially things
Speaker 1: for like if you're driving at night and you'll know
Speaker 1: no halos around headlights things like that, or you're sensitive
Speaker 1: to bright light. Yeah, yeah, you're light sensitivity. Especially for
Speaker 1: 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 reports that
Speaker 1: that it happens. Um. But and you know, some people
Speaker 1: who have and you know, enjoyed the benefits of the
Speaker 1: surgery for years, and then there are others who gradually
Speaker 1: returned to uh, to the way they were before. I'm
Speaker 1: sure that it probably since since part of the corney
Speaker 1: has been removed, I would imagine that it's probably not
Speaker 1: as uh drastic a 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 that
Speaker 1: would be a big problem because the focal point would
Speaker 1: constantly be changing then or gradually be changing. Well, guys,
Speaker 1: that's it. That's another classic episode of tech Stuff in
Speaker 1: the books. I really love looking back on these After
Speaker 1: recording more than a thousand episodes of this show, it's
Speaker 1: sometimes a journey of discovery for me to go back
Speaker 1: and look at these old episodes. And also it's just
Speaker 1: fun to think back on working with Chris Poulette. He
Speaker 1: was a great co host and editor. So Chris, if
Speaker 1: you're out there listening to this, we miss you, buddy.
Speaker 1: If you, guys, suggestions for future episodes of tech Stuff,
Speaker 1: whether it's a technology, a company, a person in tech,
Speaker 1: maybe there's someone you would like me to interview on
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