In 1948, Spanish ophthalmologist Jose Ignacio Barraquer Moner was fed up with glasses.
He wanted a solution for blurry vision that fixed the eye itself, without relying on external aids.
But the surgery he eventually devised was not for the faint of heart.
Barraquer began by slicing off the front of a patient’s cornea and dunking it in liquid nitrogen.
Using a miniature lathe, he ground the frozen cornea into the precise shape necessary to focus the patient’s vision.
Then he thawed the disc, and sewed it back on.
Barraquer called this procedure keratomileusis, from the Greek words for “carving” and “cornea.”
And though it might sound grisly, his technique produced reliable results.
So how did Barraquer’s surgery work?
Keratomileusis corrects what are called refractive errors: imperfections in the way the eye focuses incoming light.
Ideally, the cornea and lens work together to focus light on the surface of the retina, but several kinds of refractive errors can impair this delicate system.
In people with myopia, or short-sightedness, a steep cornea focuses light just short of the retina.
Those with hyperopia, or far-sightedness, have the opposite problem: light is focused too far beyond the retina.
And in people with astigmatism, the cornea has two different curvatures which focus light at two distances and produce blurry vision.
Even those with perfect vision will eventually suffer from presbyopia, or “aging eyes.”
As the proteins in the lens age, they slowly increase its size.
By an adult’s mid-40’s, the lens is too large to easily change shape and shift focus.
Glasses and contact lenses bend light to compensate for these refractive errors.
But, as Barraquer’s procedure shows, we can also alter the shape of the cornea itself; moving the focal point backwards, forwards, or pulling a divided image together.
And thankfully, modern eye surgeons can sculpt the cornea with far less invasive tools.
In corrective laser eye surgery, surgeons rely on excimer lasers.
These tools are accurate enough to etch words into a human hair.
To safely accomplish these ultra-fine incisions, they use a technique called photoablation.
This allows the laser to essentially evaporate organic tissue without overheating surrounding eye tissue.
So how does laser eye surgery actually work?
The first step is to separate a thin layer from the front of the cornea.
This can be done with either a flat, wide blade, or a femto-second laser that produces millions of tiny plasma bubbles to create a plane beneath the corneal surface.
Surgeons then lift the flap to expose the inside of the cornea.
Guided by the refractive error and the shape of the cornea, the excimer laser robotically sculpts the exposed corneal bed into the correct shape.
This process usually takes less than 30 seconds for each eye.
Finally, the flap is closed, and its edges reseal themselves in just a few hours.
Because the lasering is done on the eyeball itself, it’s described as “in situ,” or “on site.”
Its complete name is “laser in-situ keratomileusis” – but you probably know it as LASIK.
Essentially, this technique carves a patient’s contact lens prescription onto their cornea.
Like any surgical procedure, LASIK comes with certain risks.
Some patients experience slightly blurred vision that can’t be corrected by glasses.
But the technique is currently about as likely to damage your eyes as wearing daily disposable contact lenses for one year.
Today, a technique called SMILE enables surgeons to sculpt the cornea through even smaller incisions – further reducing recovery time.
And lasers aren’t just correcting the three types of refractive errors – this technology can also restore aging eyes.
In a technique called Laser Blended Vision, surgeons adjust one eye to be slightly better at distance vision and the other to be better at close range vision.
The difference between the two eyes is small enough that most patients can merge their vision, allowing both eyes to work together at all distances.
Advances in laser technology continue to make vision correction surgery more effective and accessible.
One day soon, Barraquer’s vision of a world without glasses may finally come true.
My story starts in the northern Galapagos Islands, under 50 feet of water and a big school of sharks.
I'd been scuba diving with a group of friends for about a week, and it had been glorious: manta rays, whale sharks, penguins and, of course, hammerhead sharks.
Today's dive was particularly tricky.
The surge was terrible.
You had to have your camera rig tight in and your arm out, because the surge kept throwing you into the rocks while you're scanning up for that beautiful photograph.
It was going OK, until ...
not OK.
Something was terribly, terribly wrong.
I pulled my hand back, and I had long, black sea urchin spines all the way through my gloves, which meant all the way through my hand.
Now, this is bad.
I mean, obviously when you have something all the way through your hand, it's kind of bad anyway, but in this case, sea urchins have a venom on them that, if you've ever tangled with them, you know that a sea urchin spine in you gives you horrible, painful inflammation.
But that wasn't even topmost in my mind at this point.
This did not look real.
I could not believe that this was my hand.
Now, in a crisis, I tend to disassociate into, like, little scientists, and I start talking very analytically.
All analysis was gone, adrenaline brain kicked in, and I just yanked the spines out.
I don't remember doing it.
I just remember thinking, "I can't get my glove off with these in here."
I do remember taking the glove off and a big plume of black coming up in front of my face.
And biologist brain now shows up and starts freaking out.
"How could all that toxin have gotten into that wound already?"
Well, physicist brain then shows up and very calmly explains, "No, no, no, we're at 50 feet, red wavelengths are attenuated.
That's blood -- not black.
And sharks.
So what are you gonna do?"
Well, I cranked my cummerbund down really hard over my hand, and I simply swam away.
"Let's let that big old cloud of blood dissipate a bit before we have to surface through all of these sharks."
So when I did surface, my warm-blooded-mammal brain was in an absolute gibbering panic: "They don't feed when they're schooling.
They don't feed when they're schooling.
All the way up."
And they didn't.
So apparently, they have read the same books that I have.
(Laughter) Now, it turns out, when you've been stabbed with sea urchin spines, and you're two days away from any medical help, the thing that you've got to do is, unfortunately, cook your hand.
So you put it in water as hot as you can stand, and you keep adding boiling water until you think you will go absolutely insane.
Now, it worked -- the hand itself did not work so well for several weeks after that, but eventually, fine motor skills returned.
All except for one spot, that stayed stiff and painful for weeks after the other things had gotten better.
So it turned out, I'd broken off a tip of the urchin spine in the joint itself, and that's why it wasn't getting better.
So the orthopedist says, "You know, we should get this out.
Nothing too urgent, not an emergency."
So we scheduled a small surgery for a few weeks out on a Monday.
And on the Friday before, I broke my pelvis in a horseback riding accident.
(Laughter) Yeah.
So we kind of postponed that surgery.
My broken pelvis and I were now facing six weeks on the couch, and I would have gone absolutely insane if it hadn't been for my friends.
Spontaneous parties broke out at my house every night for weeks.
I was fed.
I was entertained.
It was great.
But that kind of enthusiasm is sort of hard to sustain over the long term, and eventually it petered down to just one friend, who would send me jokes during the day and come and keep me company in the evenings -- someone I got to know a whole lot better during this period of convalescence.
And when I was finally pronounced well enough to do weight-bearing activities, we loaded a telescope in the car and drove up into the mountains to look at the Hale–Bopp comet.
Yes, we are geeks.
And got caught in a landslide.
(Laughter) I know -- like, really?
No.
Just kidding.
(Laughter) No more disasters.
No.
Just the opposite, in fact.
That was 21 years ago, and for 19 of those years, I have been married to that marvelous introvert who never in a million years would have approached me under other circumstances.
We have a wonderful 14-year-old daughter, who did all my illustrations.
(Cheers and applause) Yeah.
So, pro tip: apparently, nothing makes you sexier than needing a walker on your first date.
So this isn't a story about piercings or sharks or boilings or breakings.
It's a love story.
It's a love story with a funny little epilogue.
Now I was weight-bearing again, I could reschedule that surgery, get the spine out.
But I didn't need it anymore.
Turns out, when you break a bone, your body scavenges calcium from all the bones in your body -- and from the little sea urchin spine that you happen to have lodged in the joint of your finger.
So yes, my pelvis is now part sea urchin.
(Laughter) So to biology brain, physicist brain, adrenaline brain, warm-blooded-mammal brain, I get to add "urchin brain," with all of the superpowers that that confers.
You don't need to worry, though: that I am not fully human is one of the things that my family loves the most about me.
(Laughter) Thank you very much.
(Applause)