ZZ Top’s La Grange.
That’s my recommendation if you’re going to have an MRI and want to get it started with some rock’n’roll.
Or at least that’s how I started the last MRI I had, although I didn’t exactly choose the song or the group. I just said: “I’ll take rock” when asked what kind of music I wanted.
After ZZ, we went to Life’s Been Good by Joe Walsh.
And from there, it was on to Genesis and beyond into, yeah, some pretty hard-driving tunes.
It was a good way to begin my most recent MRI experience, with familiar rock music coming through my headphones as I lay still as a stick in the narrow tube of an MRI machine in the imaging department at Monument Health’s Rapid City Hospital.
It wasn’t my first time with the headphones on and the music blaring. And it wasn’t my first time in the tube. In the last year alone, I’ve had five MRIs. Well, seven, I guess, if you consider that in order to get one of those MRIs just right last September I had to go in the tube three times in one day.
Once early in the morning (my favorite time to have an MRI - I seem to be more relaxed in the tube), once right after lunch, and a third time shortly before closing. The MRI technologists kept calling back to tell me the radiologist wanted one more image.
Which was OK with me. When you’re talking about a lesion in your brain, you want those folks to have a good look at it.
And during those times in the tube, I heard some fine music — blues and jazz and country to go along with the rock — and also listened to some of the weirdest sounds you could hear. If you’ve been there and done that, you know the sounds.
For those who haven’t been there and done that, they give you earphones and offer you a choice in music. I think it’s meant to cover up some of the stranger, louder of the sounds — the buzzes, rattles, rumbles, and squeals — and also to keep you occupied while you lie still in pretty close quarters for, oh, half an hour or so.
Longer, I guess, in some cases, shorter in others, depending on what they’re looking at or for.
I don’t particularly enjoy that part of it. The tube part. The lying still part. But the music helps. So the time passes fairly quickly. And, oddly enough, sometimes the strange sounds of the MRI machine can also be entertaining, in their own way. Some are bothered by them. Others don’t pay much attention at all.
At least, that’s the word from Michael Rocha, manager of medical imaging services for Monument Health in Rapid City.
“It’s hard for folks to wrap their heads around why it’s doing it,” Rocha says. “I have a pretty standard explanation for it.”
Rearranging your atoms for the computer to read
The explanation begins, quite naturally, with the “M” in MRI. That stands for magnetic.
“The entire machine is a giant electromagnet,” Rocha says.
Then it moves to “R” for resonance, which is where things get a little more complicated.
“Put a human in the MRI machine, with the body being mostly water, and those hydrogen atoms will align themselves to the magnet. Once you go in, all of your atoms align with the magnet,” Rocha says. “Then radio pulses are used to energize the atoms, and as they return back to try to align themselves with the magnet, they give off a low-radio signal that the machine reads.”
The resonance happens when you introduce a radio pulse that changes the direction or configuration of the hydrogen atoms. As they return to their original alignment in the pull of the magnet, they give off signals that the machine can register. They’re resonating within a coil that receives the signal, and creates an image read by a computer.
“The computer understands that data and puts it into a 3-D phase that shows you spacially what you’re seeing,” Rocha says.
Magnetic resonance imaging.
And that giant magnet? It’s always turned on. That way anybody who goes into the scan room with the MRI machine — including the technologists — has to make sure they aren’t coming in with any ferrous metal, which contains iron and can be pulled to or toward the magnet.
Before you have an MRI, you fill out a screening form that asks all kinds of questions: Do you have any shrapnel in your body or metal shards of other kinds. Do you have a pacemaker, cardiac pacing wires, aneurysm clips, inner ear implants, shunts or ports, artificial heart valves, stents, coils or filters, artificial joints or orthopedic pins, insulin, or other infusion pumps, detached-retina clips, or eye springs? Some can cause problems. Some can be removed. Some can mean you can’t have an MRI.
Shrapnel, for example, can be a big problem.
“We still get a lot of Vietnam vets with some shrapnel — pieces of the outside casing of grenades or land mines. And typically we can’t do the MRI in those cases,” Rocha says. “The problem is it could pull it toward an artery or something vital.”
X-rays or CT-scans can be used in such cases.
Some years back, Rocha had a patient who got shot as a kid and still had a pellet under the skin at his wrist.
“He didn’t even remember it was there when he filled out the screening questionnaire,” Rocha says. “But as he got closer to the magnet he said ‘Something’s pulling on my arm. You could see it as if the skin on that spot had been pinched. We took him out. The bb might not have moved, but there was a risk of burning.”
Take out the earrings, and maybe the false teeth, too.
You can’t wear your rings or your glasses or your belt buckle or even your jeans with metal snaps. I’ve had enough MRIs that I show up wearing pants with a plastic zipper and snaps, a pullover shirt, and a pair of slip-on leather shoes.
Body piercing jewelry should be removed. And false teeth, too, if they’re the older kind with metal wires. Today’s dental implants, like the two I have, are fine.
“If you have anything that’s ferrous, it’ll fly like a projectile, faster than you can even see,” Rocha says.
If you look around the internet, you can find other examples of people who accidentally took ferrous metal into the MRI room.
In Rochester, New York, an off-duty police officer was going in for an MRI. An imaging technologist told him he could leave his handgun in the patient-waiting area, but the officer misunderstood and took it with him into the scan room as the technologist was distracted while entering some of the officer’s personal data into a computer. As the officer raised the gun to put it on top of a cabinet, the magnet pulled it out of his hand and it flew across the room to slam into the MRI machine, discharging on impact. The bullet hit a wall and no one was hurt.
There has been tragedy, too. In 2001, a 6-year-old boy died in a New York City area hospital when an oxygen tank someone had brought into the scan room was pulled across the room, striking the boy in the head.
So, it’s serious business working around that giant magnet. That’s why it’s important for people to carefully fill out the screening sheet and also for those who operate the machines to understand their power. Rocha gives examples to new staffers to show what the magnet can do.
In one, he puts metal paper clips into a plastic container with a lid, wraps it with tape so the lid won’t fly off and the container won’t scratch the MRI machine.
“Then I have them hold onto the cup and walk slowly toward the MRI machine, and it just rips the cup out of their hands,” Rocha says. “It gives them that visual, a tactile sense of how strong that magnet really is.”
How strong is it? About 30,000 to 60,000 times stronger than the Earth’s gravitational pull, depending on the size of the magnet.
Those gradient coils within the machine get energized with electricity and vibrate, making different noises depending on how they’re being used for imaging sequences by the technologist.
“Each sequence has its own pulsing. And each sequence lasts three or four minutes,” Rocha says. “So you’ll hear the same repetitious sound for three to four minutes. Then it will stop. Then you will have a different rhythmic pulse sound.”
Keeping track of time in the tube by the number of songs
That’s kind of how I keep track of how long I’ve been in the tube. I figure an average song lasts three to five minutes. So I keep track of the number of songs in my head and figure about where I am in an imaging process.
You don’t have to have music in there. But most people do, according to Rocha.
“Some people have a very particular kind of music they want to listen to, or some just have you throw on some oldies or ‘50s music,” he says.
The technologist can speak to the person in the MRI machine through the headphones. And some people like to be talked to regularly throughout the process.
“I’ve had them where every time a sequence would stop, I’d say ‘OK, now we’re going to have another one for three or four minutes,” he says.
In some MRI’s there’s even a video system with sort of “periscope goggles” you can put over your eyes and watch a video during the scan. Monument doesn’t have that.
About five percent of those who have MRI’s need to be sedated, because of claustrophobia. And if someone can’t be sedated for some reason, or if they’re too big — more than 500 pounds, say — they might need other imaging options.
Those could include so-called open MRIs, which Monument doesn’t have in Rapid City.
“With open MRI’s you have two magnets set up like a hamburger bun with you in the middle, so you lose that complete circle and the magnetic strength is much less,” Rocha says. “It affects image quality and takes longer to do the same type of scan.”
The nice thing about MRIs is they don’t expose you to any radiation. But sometimes they can affect the inner ear a bit and leave you feeling a little dizzy or light-headed. I feel a little that when I come out of the tube, but mostly, I think because I’ve been lying flat on my back for half an hour or so.
I’ll be seeing my local neurologist in a couple of weeks to talk about the most recent MRI and whether I’ll need another one in six months or a year to continue monitoring the lesion in my brain.
Which would mean another trip into the tube, and some more rock’n.roll.
Or maybe next time I’ll go with some blues instead.
I’m pretty sure Stevie Ray Vaughan could get my mind off those weird sounds.
