(classical music)
- Hi, I'm Jonathan and welcome to Brain Stuff.
Now when was the last time you got
to use an eyelid speculum?
You know those small metal prongs that push
your eyelid open, Clockwork Orange style?
Well, viddy well, me droogies, I hope
the answer is never.
But, if you have been subject to one
of these uncomfortable devices, it's probably
because you had corrective surgery to your vision.
Like I did.
Four days ago.
Well, see our corneas are like windows
that allow light to pass through to our retinas,
where it's converted to electrical signals
in our brain.
So, if you have eyesight problems, it's usually
because your eye can't focus on an image
onto your retina.
For centuries, we've relied on external lenses.
Like, glasses or contacts for correction,
but with modern technologies, surgeons
can actually alter the shape of the eye
itself, using lasers to change its focal point.
So the most popular technique is called Lasik,
which stands for
To qualify for Lasik, you'll need to meet
a certain range of vision, corneal thickness,
and pupil size.
Once you've passed that pre-op assessment,
you come back for the actual Lasik process,
conducted by both the surgeon and the
technician operating the laser machine itself.
They'll put a topical anesthetic in your eyes
to numb any discomfort, or at least most of it.
But that's good, because the next step
is they pry open your eyes with special tape,
and then they use that good ol' eyelid speculum.
Then, they'll calibrate the laser and mark
your cornea for alignment.
Using a suction ring and an extremely precise
surgical blade called a microkeratome,
the surgeon cuts a flap in your cornea
and folds it back.
They may also use a laser to do this.
You'll be asked to look at a red light,
which isn't actually the laser, but it helps
to center your eye.
Now it's laser time!
So, a laser mixing reactive gases like
chlorine and fluorine with inert gases like
argon, krypton, and xenon, produces a tightly
focused beam of ultraviolet light that
vaporizes a microscopic portion of the cornea.
It's as pleasant as it sounds.
Now this is actually a cool laser that doesn't
heat the surrounding air or the surface of your
eye, instead it breaks down the molecular
bonds of organic materials.
Now the beam itself is microscopic
and less than a nanometer wide.
The surgeon reshapes the cornea by controlling
the size, position, and number of laser pulses applied.
Surprisingly, this only takes a few seconds.
In my case, I was in and out of that room
in five minutes.
But, when it's all finished, your corneal
flap is replaced and a small antibiotic is added.
The cornea heals and re-bonds immediately,
naturally sealing itself again.
Taking into account the time for both eyes,
the entire procedure is done in only
15 to 30 minutes, from the time you walk
in the door to the time they kick you out.
After the operation, they'll give you something
to cover up your eyes.
For example, I'll be right back.
These.
Pretty boss, right?
So essentially, it prevents you from touching
your eyes or getting anything in your eyes,
but lets you see enough to get around.
So you'll wear them for the rest of the day
and then you end up sleeping in a mask
so that you don't rub your eyes in your sleep.
Now, you're probably asking,
but Jonathan, couldn't there be any
side effects, I mean, when a doctor is shooting
a laser in your eye?
Well, of course there could.
Now, most commonly, eyes can be under corrected
or over corrected, or you might get a small
wrinkle when the flap is replaced,
and that could cause a blur.
But for the most part, these are easily fixed
with a second procedure.
And I'd be lying if I said there wasn't
at least a chance of partial or complete blindness.
But it is minuscule compared to the success rate.
This is especially true if you're seeing
a reputable doctor, like I did.
I saw a leader in the field, but keep
in mind there are so many unscrupulous
practitioners out there, that the FDA
had to issue a stern warning about dodgy
sales pitches underplaying the risks of Lasik.
But 25 years after it was invented by
Gholam Peyman, Lasik is safer than ever before.
There are other types of eye surgery too,
including radial keratotomy, automated lemellar
keratoplasty, and photo-refractive keratotomy.
All of them, however, involve slicing
up your cornea to some degree.
Now I've got a question for you.
Have you had Lasik or any of these other surgeries?
And, how'd it work out for you?
Let us know in the comments below
and make sure you share this video
with everybody you know or they will
come and gouge out my eyes.
And if you enjoyed it, like it and subscribe
to our channel.
We'll see you again soon.
(electronic music)