字幕列表 影片播放
[♪ INTRO]
Modern medicine is pretty incredible.
But even in a world where open-heart surgery and brain-scanning headsets
sound almost mundane, some medical advances do truly seem
like science fiction.
So here are five recent developments that sound like they're
straight out of the future, but are already around today.
Robots and surgeons go way back—in fact, robots have been
in operating rooms since the late 1980s, helping out
with all types of routine procedures.
But in February 2020, surgeons in the Netherlands kicked things up a notch.
They used a very precise robotic arm with teeny tiny tools
on the end to operate on blood vessels just a few times
the size of a human hair.
It was the first human trial of robot-assisted supermicrosurgery,
which is surgery on vessels smaller than eight-tenths of a millimeter.
Surgeries at these scales are really tricky for humans,
because our hands do shake—maybe just a little bit,
but at these scales, every millimeter counts.
So only highly-trained surgeons are capable of doing these procedures.
One of these very precise surgeries, called
a lymphatico-venous anastomosis, or an LVA, is a treatment
for breast cancer patients whose lymph isn't draining properly.
Lymph is a fluid that transports white blood cells
and other nutrients around the body—and when it doesn't
drain properly, it can cause swelling and pain.
But with surgery, tiny lymph vessels can be connected
to blood vessels to give the lymph another way out.
This surgery is at the very limit of human capabilities,
but the team of surgeons and roboticists in the Netherland thought
they might just be able to make the procedure easier and safer.
They devised a robot called MUSA, which mimics a surgeon.
It has two arms that go over the patient, with tiny surgical tools
on the ends instead of hands.
To manipulate the robot, a surgeon looks at the patient
through a microscope and moves a set of controllers
as if they were operating directly on a person.
But it's the robot's tiny tools that are actually
performing the surgery.
The robot mimics the surgeon's movements exactly,
except it filters out tremors.
It also scales those movements down, since the surgeon is looking
at the patient through a microscope and making bigger motions.
Out of 20 surgeries, MUSA assisted in eight, and all of them
were a success.
Unlike a human, the robot didn't twitch or get tired,
and it could hold an awkward position forever if it had to.
This success is really exciting, because a robot like MUSA
could make this type of complex surgery possible
for more surgeons—which means more people could get
the treatment they need.
The reason a lot of people who are paralyzed can't move their limbs
is because the nerves that should be taking signals from the brain
to the rest of the body aren't working the way they should.
And for many people with this kind of nerve damage,
the condition is permanent.
But in a case study published in 2019 in the journal
The Lancet Neurology, a team of researchers in France found
a creative way for a man who was paralyzed below the neck
to control his limbs again.
Their idea was to bypass the nerves completely—by recording messages
straight from the brain and sending them to a machine
that could carry out its orders.
The solution combined incredible advances in both
brain scanning and robotics.
First, the team inserted two small implants into the patient's brain
to measure activity in the areas that control movement.
The implants were hooked up wirelessly to a computer system,
which decoded the brain signals and translated them
into instructions for a virtual avatar or a full-body exosuit.
But it was not as straightforward as it sounds.
See, scientists know which regions of the brain broadly
control movement, but for this contraption to work, the system
needed to match up an exact pattern of active brain cells
with a specific movement.
And that's not exactly easy. Like, what does [this] look like
on a brain scan, compared to, like, [this]?
The team started by having the patient think about a specific action
—like rotating his wrist or moving a wheelchair forward.
The computer—which was hooked up wirelessly to his brain—
would record the signals that thought created.
Then, over the course of two years, the computer created a model
of the patient's brain—basically like a dictionary that matched
brain patterns to movements.
In a way, he was both training the computer to understand
his brain signals, and training himself to think in a structured
and focused way that a computer would understand.
And in the end, the patient was able to use the system
to do all sorts of things!
He drove a wheelchair and made virtual hands do things like
turn over or touch a target.
He also gained the ability to start and stop an exoskeleton.
It was attached to a harness mounted on the ceiling, so while
he wasn't completely independent, he could essentially walk.
Now, this wasn't the first time scientists created
an interface between a brain and a computer, but the small surgery
it required was much less invasive than other methods.
And while it's still a long ways from widespread use, it's a big step
toward developing a way for paralyzed people to control robotic limbs
with nothing but their thoughts.
In March 2020, doctors in Oregon announced that they had used
the DNA-editing tool CRISPR-Cas9 in a living person
for the first time.
Their goal was to treat a rare genetic condition that causes blindness by…
just… fixing the faulty code in the DNA.
Which is actually possible because Cas9 is an enzyme
that can cut apart molecules, and it allows researchers
to snip a strand of DNA at a precise location
and replace faulty code with new instructions.
This technology itself isn't that new.
Scientists have been using it to edit genes in bacteria,
fruit flies, plants, and other organisms since 2013.
And in a different study, also published in February of 2020,
doctors actually edited the white blood cells of three people
with cancer—but they did the editing outside the patients' bodies.
That same month, though, the team in Oregon took gene-editing
a step further when they announced that they had used it directly
in the human body to edit the genes of living cells—
although when we filmed this video,
they didn't yet have their results.
This clinical trial involved a patient with a rare inherited
eye disease called Leber congenital amaurosis, which affects
the cells of the retina and causes blindness.
And this disease can be caused by a mistake in a gene called CEP290 -
that's what researchers wanted to fix.
In the trial, doctors used a needle to inject a few drops
of a solution containing the CRISPR-Cas9 system into the space
just behind the retina.
The idea was that CRISPR-Cas9 would find the cells of the retina
and snip away the mutation, leaving behind a functional gene.
If it works, it should be a permanent cure.
And the retina is a good place to test out gene editing in humans,
because it's isolated from the rest of the body—so changes made
on one eye won't affect any other part of the body.
After all, there are a lot of valid reasons to be concerned about
doing gene-editing in humans—but this is a pretty safe place to start.
And if the procedure does cure the patient's blindness,
it's not just good news for people with this rare disease;
it could open up the possibility for other gene therapy treatments as well.
These days, there's not much you can do if you scrape up a knee
or get any injury that breaks the skin.
It's just got to heal, and it takes as long as it takes.
But in 2018, researchers at the University of Wisconsin-Madison
reported that they had built a device that healed injuries
in rats four times faster than they heal on their own.
The device itself is really simple: It's basically
a little electric bracelet that delivers gentle electric pulses
to the site of an injury.
Now electricity naturally plays a role in helping wounds heal.
Scientists have known since the 1800s that anytime you get an injury,
your body naturally creates an electric field around it.
And in more recent studies, researchers have even watched cells
move around and restructure themselves in response
to an electric field.
You know. As they do.
They still don't know exactly how the cells are responding
to that electricity, but electricity seems to promote the growth
of new cells, which is what it takes to close a wound.
So this device was designed to speed up healing
by providing additional electricity to the injured region.
And in rats, the results were kind of incredible.
An injury that normally took almost two weeks to heal closed up
in three days.
Eventually, researchers hope to test something like this
on human skin.
And in the meantime, they've found evidence that this technology
may even have an extra perk—it might reverse baldness.
In a separate experiment, they applied a patch with
the same technology to mice with a genetic condition keeping them
from producing certain chemicals that make hair grow.
So the mice are naturally hairless, but after just nine days,
they'd grown hair under the electric patch.
Researchers believe the patch works by stimulating the cells in
the area so they release those chemicals that tell hair to grow.
Now, you may have noticed that your head is not mouse skin.
But if tests in humans go well, products with this technology
could eventually hit the market, but in the meantime—
in case you need me to say it—don't try this at home.
Everywhere around the world, there are more people
who need organs than there are donors.
Like, right now, there are over 100,000 people in the U.S.
waiting for kidneys.
And even in a record-setting year like 2019, fewer than
a quarter of those people will get them.
So lives depend on finding more kidneys.
And in 2015, doctors in the U.K. found a new way to put kidneys
from deceased donors back in business, using a technique
called ex-vivo normothermic perfusion.
This technique uses a jolt of nutrients to repair kidneys
from deceased donors and make them usable again—which is not easy.
Because, as soon as a person dies, their organs start to deteriorate.
Doctors can slow that deterioration by chilling an organ,
but even then, kidneys have to be transplanted within a day or two,
or they're often too far gone.
This new procedure helps by putting new life into kidneys
that have passed the usual point of no return.
First, the kidney gets removed from the deceased donor and kept cold,
just like usual.
Then it has to travel—sometimes down the hall,
other times to a different city.
Once it gets where it's going, it goes into a special machine
that's kind of like a spa… but for kidneys.
It pumps warm blood and nutrients through the organ until
it's working at peak efficiency.
Then it's good to go back to work in the world of the living.
What's cool about this procedure is it doesn't just wake
the kidney back up—it also gives the surgeons a chance
to make sure the kidney works on a machine,
before it goes into a human.
Kidneys that were borderline become healthy enough
to use after this little trip to the kidney spa.
And, so far, the early results are promising.
Initial studies show that the revived kidneys are at least
as safe as kidneys typically used for transplants.
Other trials are still in progress to make sure it's completely safe,
but if things go well, this could save a lot of lives.
For now, many of these advances are proofs of concept and still
far from being your everyday reality, but they show how quickly
science fiction can become science and help us to live
longer, healthier lives.
Thanks for watching this episode of SciShow!
And a special thanks to our patrons on Patreon who make it possible
for us to share all this amazing science with you.
If you'd like to join our amazing community of patrons,
you can find out more at patreon.com/SciShow.
[♪ OUTRO]