How do MRIs work?

Published Jul 9, 2019, 8:00 AM

What is an MRI and how does it work?

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Hey Daniel, have you ever broken a bone? I?

Have, but it's kind of embarrassing.

What happened?

Well, the first and last time I ever went snowboarding, the first time down the mountain broke my wrist.

Really the first time? What happened? You didn't see that tree coming.

No, honestly, I was trying to avoid snowboarding over my girlfriend at the time, so it was a bit chivalrous.

You took a hit for the for the team.

That's exactly right.

And then what happened? Did they take an X ray of you? Or how did they How did they know it was broken?

Yeah, well it hurt a lot, and then they took an X ray and you can actually see inside right, You could see that little bone was snapped off. I in the wrong spot.

Isn't that amazing? How signs can see inside of you? Him Moorhee. I'm a cartoonist and the creator of PhD comics.

Hi, I'm Daniel. I'm a particle physicist by day and a sleeper by night.

How does the word You just close your eyes and it happens.

You should try it sometime. It really does help.

Because you never remember the moment you fall asleep, right.

It's sort of mysterious. Yeah. I remember actually trying to teach my kids how to fall asleep, and then I realized I don't really know how. You just sort of do it.

You just do a podcast where we sleep.

I know we should do a whole podcast episode about that like, why do we sleep, what happens do when we sleep? Why do we need to sleep? What would happen if you didn't sleep?

So welcome to our podcast Daniel and Jorge Explain the Universe, a production of iHeartRadio.

In which we try to take your sleeping mind and wake it up to the amazing mysteries of the universe. We zoom all around and find interesting stuff and explain it to you.

Yeah, we try to permeate your dreams with thoughts of the universe and the amazing, incredible things that are happening all around you.

That's right. We are spurring the great awakening in physics by making sure everybody out there who listens to this podcast really knows what's going on. Because the universe is a crazy, amazing place and we want to share it with you.

Part of what we like to do is to explain how even everyday things around you that you may use on a regular basis work.

That's right, because there's incredible physics and the heart of the star and in the birth of the universe and in particle collisions. But there's also really amazing physics happening all around us in technology that we take for granted, in technology that we use that our lives sometimes depend on, but we don't really understand.

Yeah, it's technology that saves lives and can sort of tell you and help people.

Right, that's right. And it seems sort of like futuristic and awesome. You know, it's incredible that you can see inside somebody without cutting them open.

So today on the podcast and we'll be talking about mries. How do they work, Why do they work? Do they work?

Why do physicists want to see inside you? Anyway?

Who gave in permission to look inside of you? I think it's a real question.

What are you hiding that you don't want physicists to look inside you? I mean, if you're innocent, you'd have nothing to hide, right.

Yeah, MRIs these are it stands for magnetic resonance imaging, right.

That's right. And if you've ever been to the doctor and you have an injury or a broken bone or something funding going on inside you, or are you're just curious, like what's going on inside of me? Let's get myself checked out? Then you know you have several options for looking inside you. You can do an X ray, you can do a cat scan, or you can do an MRI.

You can do a lobotomy, you can.

They can just slice you like a Deli ham and check you out. But the nice thing about some of these is that they don't need to open you up. Right, it's non invasive, and you know that there are risks every time you do surgery, and so it's a great advantage to get to figure out what's going on before they go in and cut anything.

So MRIs are These are the kind that you sort of go, you lie down in a little platform and then they roll you into this kind of giant donut looking thing.

Right.

Yeah, it's like a big physics machine. Right. It's big, it's round, it glows, it makes really loud clunking noises. It takes a while, and I've bet everybody who lies in an MRI is wondering, like what is this thing doing? Like is it zapping my brain? How does this thing actually work?

Yeah, and it's because it doesn't really touch you, right, You just lie on this little platform and somehow it takes pictures inside of your body.

Yeah, exactly. It can show you what's going on. And that's pretty powerful if you're wondering if you have cancer or if you have a tumor, or if there's you know, if your body's filled with bananas or something. MRIs can answer that question, right.

And what's amazing about MRIs, I think, is that they don't just take sort of like a picture, you know, like a like an impression, like a like a whole body picture. They really just kind of capture a slice of your body, and so you can get a really detailed model or reconstruction of your your entire all the tissues in your body.

Right. Yeah, it's really pretty incredible. We have MRI done of our daughter once, and you can sort of turn the knob and see how like all the bits of the brain and the ear and stuff are all connected. It's amazing. It's like taking somebody and slicing them like a Deli ham without actually slicing them.

Thank goodness for physics.

Have you ever seen that Bodyworks exhibit where they actually take corpses and slice them super thin?

I have, Yeah, a few times. It's pretty shocking.

It's pretty shocking, but that's basically what an MRI does also, right, It gives you all these little slices. It lets you look back and forth and see how things are connected and what's going on inside you. It's an incredible machine the body.

Yeah. I guess what I mean is, you know, like when you I think a lot of people are familiar with the X rays. You know, like if you go to the dentist or you broke a bones, they'll take an X ray of you. But an X rays is really just like they shoot you with rays. They go through your body and then they capture them on the other side, right, and so you're getting everything. You're getting like everything inside of your body's mushed into one image.

That's right. Yeah, it's like integrated along the line of the X ray. Yeah, you're learning about the whole body that way. Yeah. X rays can't do slices.

Yeah, and so the image is very like fuzzy, and it's hard to tell what's bone and what's an organ. But with an MRI, you really get like a detailed, step by step slice of the entire volume of your body.

Yeah. And the benefit is you don't get cancer causing radiation.

You get other kinds of cancer possibly.

So, I mean, you do get other kinds of radiation. But you know, X rays are dangerous. They are ionizing radiation and they deposit energy and they can break up your DNA, and there's reasons why you should be careful when you make the decisions about having an X ray. You know X rays are great, but you know you wouldn't want an X ray every five minutes. You wouldn't want an X rays on tiny babies, an anti X rayer. I'm a judicious X rayer.

I see that you should start any movement there.

With Jenny McCarthy say no to X rays every other time.

No.

X rayser are wonderful, but you shouldn't just do them without thinking about it, because there really is a health cost. But with MRIs it's different. You don't have that ionizing radiation and so you're not increasing your cancer risk. Even though it does sound crazy and feel weird to lie inside this tube for an hour.

Have you ever taken an MRI of yourself like I've had my MRI taken. Have you ever done it on yourself?

I have had an MRI done once of my leg because I tore a muscle.

I had the MRI of my brain and my head done and they gave me the data.

Whoa and what question were they looking to answer there? How does this guy survive with no sleep? Is it just a bunch of monkeys and bananas inside there?

Where did all those amazing funny ideas and creative genius come from? That's what they wanted to know, surely for posterity, But no, it's weird. It's weird first of all because you kind of you get a sense of what your head looks like without hair. I mean, no fans do ball people out there, but it's kind of shocking if you always had hair to suddenly see kind of like the outline of what your head looks like. It's kind of that's bizarre thing number one. But then it's really weird to see all the you know, your eyes balls, and the passages of your nose and your tongue and think that like that's also you see all the fillings in your teeth, which is you know, a little embarrassing.

Yeah. For me, it really highlights how much our bodies really are a machine. You know. I like to think of myself as a person and the mechanics of what supports that. I like to sort of abstract that away and think of myself with my identity, my personality, my thoughts. But when you look inside yourself, you see you're this basically this meat machine, right, and this organic robot, and it all has to work and pump and move and squish all the time, and it's incredible that it actually works. Ever, not to mention like mostly working for like seventy years at a time.

No, I think that's the name of a heavy metal band meat machine machine. But anyway, so we were wondering how many people out there know how a MRI machine works. You know, a lot of people get them for various reasons and they can help save lives. But we were wondering if people out there knew how there's amazing technology works.

Yeah, so I walked around camp as they usually do, and I ask people if they knew what is an MRI and how does it work?

Would you know how to respond if somebody asked you how an MRI works. Here's what people had to say.

It has to do with strong magnetic fields.

Okay, so how does that let you take a picture of the inside of your body?

I'm not really sure. I'm probably there. The magnetic field will go through a certain part of your body and depending on I guess how dense or how that the properties of that body part, it shows up defferently with an image. It's a machine which scans you for abnormalities within the body.

Do you know how it works? How does it see inside you?

My guess would be radiation of some sort putting.

I think you drink something.

They're able to see it.

Like if something's wrong with you, you know, you would get an MRI to pretty much figure out.

It's more kind of like of an extra skin. I think it's X ray or something.

Sure an MRI is used, or yeah, it's and your brain?

Right? How does it work? How does it scan your brain?

I would assume like similar to what they use like for X rays. So like maybe like some sort of laser. I don't know, laser, I don't know, no MRI.

Actually, I think it scuns your brain or your organs and like gives you the destination of where is the tumor or whatever it is.

I don't know, I have no idea. So what did you think of those answers? Impressed or not?

Well, it's interesting most people sort of knew what it was, so they know that it's kind of a scan of your body for medical reasons, and they kind of related it to X rays.

Yeah, that's right, everybody seemed to have an understanding of what it's for, why you might do it, but almost nobody actually knew how it worked. And you're right. People thought about it the same way they sort of think about like X rays or lasers or something. Everybody thought it was shooting something into you.

Yeah, but they're not too far off, right, Like it does involve electromagnetic radiation, right, and pulses and things that go through you.

Yeah, And of course it has to. If you want to see inside something, then you have to probe it somehow, right. You have to somehow gather information about what's beyond the skin or through the wall or whatever it is you're trying to look past. And the only way really to do that is to send some kind of radiation in. But remember, radiation is a broad term. We had a whole episode about that. Radiation can just mean sound, you know, like when you get an ultrasound done, you're sending sonic radiation into your body and you're seeing how it bounces around and comes back. And that's basically that The idea behind all medical imaging is shoot some radiation in there, see how it bounces around. Because you know, if it's this kind of goop. It's going to bounce around differently than if it's that kind of goop, you know, fat versus bone versus brain, and then you can reconstruct the picture.

Yeah, so it's very different than X rays. But let's maybe for those of us who aren't not all familiar with medical imaging, maybe step us through. First of all, let's start with X rays. How do X rays work?

Right? So, X rays are also electromagnetic radiation. Remember X rays are just light right at a very very high frequency, and so they shoot them into your body. And X rays are very powerful. They can penetrate like most light, like photons that come from the sun that you can see, don't go through your body. That's why your body is not transparent, right, You're opaque. But X rays are much more powerful. They can go all the way through your body. But it turns out that X rays are absorbed differently by different kinds of stuff in your body. So, for example, bone is really good at absorbing X rays. So shoot a bunch of X rays through somebody and then try to capture them those X rays on the other side. Where you'll see is that where there was bone, for example, very few the X rays pass through, whereas where it's mostly like gas from your lungs, then a lot of the X rays do pass through, So what you'll see is like the shadow of the bones. It's like doing shadow puppets. Right, You hold up a light bulb and your hand and you can make a shadow on the wall so you can see where your hand was, right. X rays are like that, except that your body is mostly transparent X rays except for some of the stuff inside, like bones.

So you're really sort of getting the difference in transparency between the different kinds of things inside of.

You, that's right, And different kinds of light find different things transparent. Like visible light can pass through air, no problem, right, but it can't pass through a rock or your hand. X rays are a different kind of light, so they have a different set of stuff that they can go through or not. So, yeah, you're right, you're seeing the difference in transparency between bone and fat or tumors and gas and all the kind of stuff that makes up your body.

Yeah, and you sort of get the shadow of them, the impression of them on the other side on the on like a sensor or a film.

Yeah, exactly. And you know it used to be filmed. They used to like take a picture and have to develop it. These days they use a digital camera, which is why it's so fast. And the thing X rays are good at is telling like bone from other tissue. X rays not that good at telling the difference between like water or fat or that kind of stuff. It all comes out about the same and X rays. And the other thing, as you mentioned, is that the X rays pass all the way through you, so you're just seeing sort of like the overall shadow. You can't see slices. And that's why when you take an X rays sometimes ask you to turn so they can take it from the front, and they can take it from the side or from a different angle so they can get a sense for what's going on inside from shooting X rays through you at at different angles.

Who with that, let's take a break. We'll be back in just a short minute.

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So that's one way to look inside of you. But MRI is sort of smarter, right, Like, it doesn't shoot radiation through you. It just sort of like kind of it does something a lot cleverer.

Right, Well, it actually does shoot radiation through you, right, I mean, it does send electromagnetic pulses, but they're safer, right, It's not really high energy. In fact, they're very very low energy. They're radio waves, which means are very long frequencies. So they're not the kind of radiation that can like deposit energy and break up your DNA and cause cancer. And that's the problem with X rays. And that's why when you take an X ray sometimes they can be like a lead skirt or a lead helmet or something you know, or a lead jock stop or whatever to protect your all of your important bits that you don't want to send radiation into. But an MRI can use much lower energy radiation, uses.

The same radiation as like what you listen on the radio that's pumped out by radio antennis.

Exactly the same kind of radiation. You don't usually think of that as light because you can't see it, but it's all part of the electromagnetic radiation spectrum. You know. It starts out really low frequency with radio waves, comes up to visible light, and then you get UV light at higher frequencies, and then gammer X rays and gamma rays at very high frequencies. It's all sort of part of the same family. But you know, just like in families, we're all different. And so radio waves feel very different to the body than X rays because they don't deposit very much in energy, so they can't really do much damage.

All right, So step us through Daniel. How does an MRI work? And let's start maybe with the Idita is that in an MRI, you are sending radiation into your body, but you're sort of doing it proton by proton, right Like you you're trying to poke one proton inside of your body. And so how does that work? Like if you if there's a prolin inside of your body, how do you get it to light up or to see it?

Yeah? Exactly, Well, remember that protons can absorb energy sometimes so you're sending these radio waves in, and the radio waves have energy, and the idea is that you want to poke those protons and give them that energy, so they get like excited and then they relax and they send the energy back. And the interesting thing, the reason that you can see inside the body with an MRI you can see the different kinds of tissue, is that different kinds of tissue take different amounts of time to absorb that energy and then send it back. So like fat or bone or water or whatever, you poke the protons in those different kinds of tissue, some of them will hold that energy for a while and then send it back, and some of them will send it right away. So you can tell what different kind of tissues there are by by seeing how long it takes for that energy that you deposited to get sent back to you.

So it's not like you're sending X rays through and then whatever makes it out the other end you see it. This is more like you're sending rata waves in and then that lights up the protons inside of you in different ways, And depending on how they light up up and how long they take to stop lighting up, then you can tell what kind of tissue it is, or what kind, whether it's bone or fat or bananas, exactly.

And it's just like you know, when you walk along a wall and you're looking for a stud, right, what do you do? You knock on the wall and you're sending a wave in and you're waiting for that wave to come back, right, And if the wave sounds this way or sounds that way, or it takes a long time or a short time to come back, that tells you about what's behind the wall. It's the same basic idea and it's also the way we.

Like kind of like an echo, more like an echo, but with electrome, genetic radiation and quantum mechanics.

Yes, exactly, it's like an echo. And the radio wave goes in and gets and tickles those protons and makes them excited, and then it sends a radio wave back. So you have to have a radio emitter and a receiver, so it like it talks to the protons and then it waits for the protons to talk back, and based on how long it took for them to talk back, it says, Oh, this one's probably fat, this one's probably bone, this one's probably brained, this one's probably water.

This is probably brilliance in the brain exactly. Okay, cool, all right, So it's kind of like you're sending a signal in how it gets reflected back. Then you recorded when it bounces back, and then that tells you that sort of gives you the image of what's inside of your body exactly.

And then there's some really cool quantum mechanics about how you get those protons to absorb that radio information and why they send it back, and that's where the magnets come in.

And the way I understand it, it's sort of like a spinning top, right, Like you need to think of a proton as a spinning top, and so you when you put it inside of this giant magnet, it makes all the top sort of aligne in a particular way or in one direction.

Right, that's right. Because remember we talked on our quantum Spin episode about how all these little particles they're not really spinning, but they have this thing about them called spin, which gives them a little magnetic field. So think of every little particles having a little magnet in it. And so if you put a really big magnet on the outside of the body, then all the protons in your body are going to line up with that magnet. But some of them line up with the magnet and some of them line up against the magnet, but you know, they all go along that line.

And then that primes them for you to poke them right, for you to send in the radio wave, and then depending on how they react to that, that's the signal you get back exactly.

And that's that's the magnetic part. And so you send in the radio wave and then some of the ones that were not aligned flip and become aligned because that takes more energy, and so that's how they absorb the energy of the radio waves. Some of the ones that were unaligned become aligned with the magnet. So it's just like switching directions, right. They absorb that energy, but they don't they don't hold onto it for very long, and then eventually they flip back and they send the radio wave back. So that's the magnetic part. That's how you get the protons to absorb this energy. That you put them in this magnetic field that allows them to align or unalign, and that gives them an opportunity to absorb this kind of energy.

It's kind of like the spinning top. You flip it and then but then it wants to flip back, and when it's flipping back, it releases some energy back.

Right, that's right, And that's the resonance part. Remember MRI is magnetic resonance imaging, and the magnet comes from you're putting people in a big magnet. And the resonance part is the part about absorbing the radio frequency. Right. Normally you send radio wave through a body, they won't get absorbed, right, They just pass right through because they're not at the right energy to be absorbed. Remember we talked about in quantum mechanics, how like atoms have different energy levels. Right, they can't just absorb a photon of a random energy. The energy that comes in has to be the right size because for example, electrons have levels and they want to go up one level or up two levels. They are like along this ladder. So you can't just absorb any random amount of energy. You have to absorb the right size of energy. Now, normally radio waves are not the right size energy for your body to absorb. They pass right through you. But when you put these protons in the magnetic field, then they have this new way to absorb energy. And that's this resonance part the energy is the resonant energy, so the right energy to push these things to make them spin one way instead of the other.

And now is it all all the protons in your body or only certain protons?

It's all the protons that I want, man, I have total control over it.

Like in all the atoms in your body react to this signal, or only like water or how does that work?

No, all the protons in your body can react to this, right because your body is made of protons, rights, protons and neutrons and electrons, but mostly it's water, right, Like, most of your body is water. But all the protons in the nuclei can respond to this kind of thing. And there's also a really cool trick they do to allow themselves to see slices. You're talking earlier about how you could see, like, you know, just to slice through your body your shoulders, or a slice through your body at your stomach or your feet or whatever. They do a really cool trick by tuning the magnet strength to make sure that only protons in one slice are able to absorb that energy at a time.

That's where the giant magnet comes in, right, Yeah, exactly, You know, like when you're in that platform and you roll in, you go into this giant donut. That donut is basically like giant. It's really just a magnet, right, like a like a just a giant coil of wire that creates a magnet.

That's right. It creates a magnet. And the magnet is stronger on one side than on the other, Like it's really stronger your head and it's a little weaker at your feet. And what that means is that the radio waves that they send in are better absorbed by just one slice of your body. The slice of your body has just the right magnetic strength to absorb those radio waves. That's the resonance part.

That's how they can take a slice of you, right, because the magnetic field changes along your body, and so and those protons react differently depending on the slice.

That's right. Only the protons that are in the magnetic field that's the right strength are primed to absorb that radio wave and then you know, send it back. And so basically your whole body is just totally transparent to the radio waves except for this one slice where the protons will grab the radio energy and then send it back. And so it's like, yeah, it's like they can only see one slice at a time. And then you're lying there and you're hearing like clank boom, bang bom. But it's like sort of disconcerting all the weird noises that happen.

Yeah, what is that noise? Anyways? When you you know, when you're in there, you just hear like, chunk, chunk, chunk. What is And you see it on TV too, when people are getting their MRIs, you hear them, you just hear this noise going chunk chunk. What is that noise?

Oh, that's you know, just a physics y sounding noise they added to make people feel like it's worth all.

The money, just some sound editor putting in the special effects later.

Are people going to pay more if it sounds if it sounds, you know, like some physics is happening. No, there really is something happening there. That's them adjusting the magnetic field so they can see different slices of your body. Can you remember those radio waves only can talk to protons that are in a magnetic field that has the right strength. So what they're doing is they're adjusting the magnetic field. They can either slide you back and forth, but that's a little more uncomfortable, or they can leave you sitting there and they can adjust the magnetic field and so you're hearing all the coils move and whatever. So the magnetic field is now good for protons at your feet, or good for protons at your head or whatever. So they're moving which slice of your body they can talk to by changing where the magnetic field has just the right strength.

All right. So it's sort of like, can I call it quantum echo, like a quantum echo effect?

Oh, that would be awesome. Yeah, quantum echo imaging. That's cool. You should have named it that.

That's a new product name, all right. So then that gives you an image of your body because each proton, depending on what kind of stuff it is in your body, will kind of reflect that energy bag differently, and so you can sort of tell what's fat, what's bone, what's water.

Yeah, exactly. They all reflect the energy back, but they take different amounts of time. So like fat takes a different amount of time to send the energy back than water does or bone does, and that's how they can tell the difference. And that's a really cool thing about MRI. Unlike X ray, it can tell the difference between these different kinds of tissue. So it's so valuable. But you can see like, oh, there's a tumor there next to this other organ or you know, you can see the differences there, which which makes it really valuable from a medical point of view.

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I think my question is how did they figure this out? How did they ever think to use this? How did they how did they come up with a idea to use it to look inside your body?

Yeah, well it came out of people doing basic research with atoms, you know, and they were, you know, like, let's take a bunch of atoms and put them a magnetic field and poke them, and you know, let's see if quantum mechanics works, and can we understand why they absorb frequencies you know here and there? And then they discovered, i think quite accidentally, that the relaxation time this time it takes the energy to come back is different. For different kinds of materials, and then you know, somebody had this bright idea. They're like, oh wait, maybe we can use this for imaging. And I think there's a huge field of people working on imaging and imaging techniques and new ways to see inside the body. Because you know, MRIs they work pretty well, but they're also they take a long time, and they're really expensive, right, so there are cons to an MRI. So there's a huge field of researchers working to develop better, faster, cheaper scanning technology.

My guess is that it was some physicists in a lab, you know, poking doing quantum physics, and somebody left her sandwich in the middle, and then they got this image of the inside of the sandwich. They're like, oh my god, think of what we can do.

You know, there are easier ways to tell what's in your sandwich than accidentally inventing an MRI machine. You could just open it up.

What if it's a burriedle Let's go with burrito. That's a little harder to see inside.

That's true. There's no non invasive way to see what's inside of burrito.

Yeah, I guess you can eat it.

Yeah, exactly, that's that's definitely a destructive way.

Of seeing it, all right, So that's kind of the general picture of how MRI's work. That's pretty cool.

Yeah, And you know, every time you're getting an MRI, it means that they're sending these these pulses into you and there's a very strong magnetic field that's applied to your body, and as far as we know, there's no adverse health effects to having a strong magnetic field. You might be thinking, oh my gosh, they're sending this magnetic field in me and all my protons are getting pointed in one direction, and that sounds really destructive. But as far as we know, you know, getting your protons to align with the magnetic field doesn't hurt you.

Unless you're a robot, then that might be a.

Pro or actually, this is serious, unless you're partially a robot, Like if you have metal screws or something inside of you, then MRIs could be dangerous because the magnetic fields could like pull them out or you know, rip out parts of you, and that would be pretty bad.

Yeah.

Yeah, I've heard of stories in MRI last where people accidentally bring their keys in and then they get you know, they fly through the room, across the room and get stuck on the magnet and they really have to like they can't pull them out because it's so strong. You can't just pull the keys away, and so they have to shut down the whole thing just to get that person's keys.

That's right, I got to go home. My keys are stuck to the MRI machine. Yeah, well there's that aspect. But also while it's flying through the air, that thing is like a bullet, you know, that could really hurt somebody. We have the same problem in particle physics because we have really really strong magnets around the collision point and we use that because we want to bend the particles. We see how fast they were going. And anytime you turn on the magnet, if this is like a loose screwdriver, that's a bullet that could kill somebody.

So it's pretty cool technology, and so there are some pros and cons. So the pro is that there's no radiation that can kill you like X rays.

Right, Yeah, X rays and cat scans all those come with significant doses of radiation. And more cat scans and X rays, X rays these days, they've they figured out how to do it with a sort of minimum amount of radiation. So you know, I don't want to scare anybody. You should get X rays at your dentist because the benefits of seeing inside your body outweigh the radiation. But shouldn't just look at like an X ray camera at home and happily take pictures of your body just for fun.

They sell that for kids there, I think.

And actually, you know, they used to have really really high intensity and X rays, dental X rays and medical X rays. They used to really crank it up because they didn't understand the dangers. And then recently, more recently, they realized they could get the same images with much less radiation, and so they've been tuning them down for a long time. But yeah, X rays have an ionizing radiation, which is dangerous, but MRIs don't, and so that's a big advantage, especially if you're dealing with like an infant or something. Right, you don't want to you don't want to pile a huge amount of radiation into the brain of an infant.

And le's it gives them superpowers? Then that maybe, uh.

That is a tough parenting choice, right, do I give my kid cancer or maybe superpowers? Yeah? I don't know, think about that.

But then the problem is that it kind of takes a long time, it's loud, and you have to sit in a tube for a long time.

Yeah, exactly, and so there are some downsides and it costs a lot, so you need your insurance whatever to approve it. But you know, it's irreplaceable. There's kinds of a pictures that can take that nothing else can do.

Right, there's no better technology for doing that, right, That's right, exactly, all right, Well, that explains it.

So if you need an MRI and you want to take a picture of your body, you should be thanking quantum physicists for developing this technology to tickle your protons and have them talk back. I'm in a little piece of fat, I'm a little piece of bone. Hey over here, I'm a cancer or I'm a cancer tumor.

That's right. And MRI is just a giant tickling.

Machine, quantum tickling. There you go.

Yeah, but it's just amazing that technology and science have worked together to create these incredible machines that can literally see inside your body.

That's right, all right.

We hope you enjoyed that and found that useful.

Thank you for listening and next time you get an MRI, they will see inside your brain an understanding of the MRI that you got from this podcast.

Oh my god, that's right. Our voices are leaving an imprint in all those people's neurons and that might show up on the MRI.

That's right. Yeah, and the MRI youll see a little picture of hoorehand Daniel going thumbs up. What And that's when the doctor goes this is interesting.

Yeah, we code it into this podcast. Is really a specific frequency that will leave an image in your brain of us.

This sounds like an awesome sci fi episode. I love this idea. Viruses embedded in podcasts that write themselves into people's brains.

Right, we are tickling your protons people.

The quantum tickling virus. That sounds like a Michael Bay movie.

Yeah, sign up canneries for that movie.

Everything he does turns to gold. All right, see you next time. Thanks for tuning in, and thanks for asking questions. If you'd like something in your world explained, send it to us at questions at Danielanjorge dot com. If you still have a question after listening to all these explanations, please drop us a line. We'd love to hear from you. You can find us at Facebook, Twitter, and Instagram at Daniel and Jorge That's one Word, or email us at Feedback at Danielandhorge dot com. Thanks for listening and remember that Daniel and Jorge Explain the Universe is a production of iHeartRadio. For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows. When you pop a piece of cheese into your mouth, you're probably not thinking about the environmental impact. But the people in the dairy industry are. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. House US dairy tackling greenhouse gases. Many farms use anaerobic digestors to turn the methane from manure into renewable energy that can power farms, towns, and electric cars. Visit you as dairy dot COM's Last Sustainability to learn more.

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California has millions of homes that could be damaged in a strong earthquake. Older homes are especially vulnerable to quake damage, so you may need to take steps to strengthen yours. Does it Strengthen your House dot com to learn how to strengthen your home and help protect it from damage. The work may cost less than you think and can often be done in just a few days. Strengthen your home and help protect your family. Get prepared today and worry less tomorrow. Does it Strengthen your House dot com

Daniel and Jorge Explain the Universe

A fun-filled discussion of the big, mind-blowing, unanswered questions about the Universe. In each e 
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