It wasn’t a big deal for me. I did have to go all the way in, unlike with the CAT scan. They gave me earplugs that were actually rather good. Being completely still is hard, but you only actually have to be still when it is scanning, and it beeps to warn you.
I seem to remember it being open at the end, though. But I could be misremembering. Oh, and they gave me a pillow for my knees and made it relatively comfortable.
Note that the duration varies a lot but is likely to just be a minute or two in the bore, and maybe only 30 seconds with no one else in the room.
It varies a lot because unlike with a CT scan, there are many different kinds (modalities) of scan that can be performed. The vanilla quick look is just a few tens of seconds.
Only if they have reason to look for something quite unusual, or nothing was found in the regular scan, is there a chance of the much longer durations one or two posters mentioned here.
IANA radiographer / radiologist, it was just my master’s thesis.
A couple of decades ago, my mother was supposed to get an MRI for some reason. I didn’t think she was claustrophobic but she was freaking out over it, so they gave her valium but that didn’t help. (I think they even upped the dose.) So eventually, they put my father in there, sitting in a chair and holding her hand the entire time. That allowed her to stay calm enough to get through the procedure.
I didn’t find it any more alarming than the reason I was in there in the first place (had had a TIA that evening). OTOH, I have no known claustrophobic tendencies. It’s VERY loud in there, even with the earplugs they provide, and a bit on the warm side. I only had my head scanned, but the machine being used probably could have done full-body if needed. I have no clue how long I was in there, TBH.
I’ve heard that a patient can ask for a mild tranquilizer if there’s a claustrophobia issue, but check with your doctor or the techs on that one.
30 seconds?
I doubt the machine can get up to speed in 30 seconds. IANAD and may well be wrong but 30 seconds is nothing like anything I have heard for an MRI.
Personally, I was in for 30 minutes (give or take).
30 minutes with no one else in the room? In the bore?
That’s crazy long. The longest I’ve ever had was 45 minutes total time with only about 2 minutes with no one in the room at a time. And that was for DTI, one of the most complex modalities.
Definitely.
It was not fast at all. As I mentioned above, I even managed a short nap.
They scanned my whole body, head-to-toe, if that changes anything.
Yep. Get the Valium. Makes it way easier.
I have about every phobia there is. I’m more afraid of wide open spaces than tight ones, tho’
(The lil’wrekker says I have Phobia-phobia)
Ok well, as I say, IANAD.
Well done for getting through that, I think even someone without claustrophobia would find that tough.
In my case drugs (hospital administered) and exhaustion helped me kinda nap through it.
I had a cardiac MRI and it was around half an hour and there was nobody else in the room until they were all done and came to help me back out.
They said it was a wide bore but it didn’t feel all that wide to me; but it wasn’t awful. I could see a bit out past my feet, the end was open; and I managed to convince myself that I could squirm out on my own if nobody ever showed up to pull the tray (or whatever they call it) back out that I was lying on. That was probably true but, as I knew perfectly well, short of civilization or at least the immediate environs ending in a very sudden manner somebody was coming to pull me back out. I had an emergency doohicky to squeeze if I couldn’t stand it and somebody would have come immediately (though, as has been said, it would have ruined the test). Noise was not continuous but intermittent, and not unbearably loud when it was. ETA: and, luckily, it didn’t hit any of the frequencies which I can’t stand.
I didn’t ask for, or need, any drugs. Mileage does vary.
TBF: I didn’t need drugs because I was claustrophobic. I needed drugs because I was in pain and could not lie still for 30 minutes. But yeah…YMMV.
I had a head MRI earlier this year, and I’m mildly claustrophobic. Having something close around my head, and near to my eyes is exactly the kind of thing that triggers me, but it wasn’t a big deal. I just closed my eyes.
Really, that’s all that was necessary to ease my anxiety. Air flows freely, so with my eyes closed I had no way to tell how close things were.
One bit of advice. Have a genre or style of music in mind. I did it without any music because my brain froze when they asked what I wanted to listen to. I was busy keeping the anxiety down about the potential claustrophobia, and I was in no place to come up with a style of music.
I had an MRI a few years ago when I tore my rotator cuff. I’d never had a problem with claustrophobia before but I did when they put me in there. I didn’t last long before I had to ask to be taken out. They rescheduled it and advised me to ask the doctor for prescription for Valium. It helped a lot. I was still edgy but I could stand it. It was also very uncomfortable for me to lie on my back and it helped me manage that better too.
I also got a washcloth to put over my eyes so I couldn’t see how close the walls were inside. That helped a lot too. They gave me earphones which I had them set to geezer rock. It cut down on the noise but I could still hear it. The music wasn’t quite enough to distract me so I just mentally counted until it was over to keep my mind occupied.
It is not exactly moving magnet, it is a magnetic noise, the magnets are fixed in place, they do not move around (hopefully!), but they change shape slightly when submitted to strong magnetic fields. It is technically called magnetostriction, it happens so fast that you perceive it as noise. The magnets are very cold (liquid Helium level cold) and superconducting, moving them would spoil the whole machine. MRI machines are a little technical wonder, when you think of them and how they work. We will miss them if we ever run out of Helium.
Concerning the procedure: No, it was not scary at all for me. I found it very interesting and now I am jealous that other people got a CD with the images and a program to see them. I did not.
I’ve had a few. The worst was in an older machine, in a very small room, and it was just HOT. Normally they are in a very cool room; this one was uncomfortable.
Otherwise, IME it’s no worse than being in a small camping tent. There are holes at either end, so no fear of running out of air, which is what drives my claustrophobia.
Usually they have a big triangular pillow they can put under your knees. It is super comfortable for back strain so be sure to let them know you need it. If you put your knees up unsupported you may have trouble holding them there before it’s all over.
I’m not sure that this is accurate.
The main magnet in an MRI, the one that is typically around 1.5 Tesla, is a superconducting electromagnet, it doesn’t change, and isn’t turned off, except in an emergency.
Meanwhile there are gradient coils, which produce a much weaker magnetic field, across the three spatial dimensions.
They need to rapidly change in field strength as part of spatially mapping the signal. The rapid changes in current through these coils cause them to vibrate. I don’t know if this vibration is caused by magnetostriction…that’s beyond my physics paygrade.
The gradient coils are cooled, but just watercooled AIUI.
MRI: Construction and physics (plain Wikipedia):
The RF signal may be processed to deduce position information by looking at the changes in RF level and phase caused by varying the local magnetic field using gradient coils. As these coils are rapidly switched during the excitation and response to perform a moving line scan, they create the characteristic repetitive noise of an MRI scan as the windings move slightly due to magnetostriction.
[…] MRI requires a magnetic field that is both strong and uniform to a few parts per million across the scan volume. […] Most clinical magnets are superconducting magnets, which require liquid helium to keep them at low temperatures. Lower field strengths can be achieved with permanent magnets, which are often used in “open” MRI scanners for claustrophobic patients.
Of course Wikipedia is not always reliable, but for technical details I find you can usually broadly trust them (as opposite to political matters, for instance). If somebody knows better, I am all ears. But that is what I was told long ago, reading that article seemed to confirm my preconception. I hope I am not reading it wrong, that is what preconceptions do to you sometimes.
Right but I think on the superconducting thing I think it’s slightly misleading how it’s written there.
The main magnet is supercooled. The gradient coils (the things primarily responsible for the noises), are not.
Thanks for the correction, I had read that as “all the magnets are supercooled”.
Still an impressive feat of engineering, I hope somebody received a Nobel Prize for that (or CT or PET or the like).