MRI question


My son is having an MRI scan next week following a case of optic neuritis. The letter states he is having a head Mri, diffusion weighted mri and an orbit mri??? - Could anyone tell me what this entails so I can prepare him before he goes.



I don’t know about the diffusion weighted MRI but I had a head and orbit MRI after a case of optic neuritis.

Basically it’s an MRI of the brain and the eyes. You go in, get changed into a gown, remove all metal from your body and lie down. For one brain scan I just had to lie still. For another I had a plastic brace around my neck and head to keep me still.

My advice is to close your eyes as soon as you lie down and don’t open them again until you are out because it can be very claustorphobic. He will be given a little panic button to hold which is reassuring more than anything, and the machine is air conditioned so you feel a nice cool breeze.

He’ll get a set of headphones which may or not play music. The machine is quite loud and maked various banging noises on and off. The technician can speak to you through the headphones also.

Sometimes they do a contrast scan which involves doing a scan and then injecting you with a dye and doing the rest of the scan. I think this shows up inflammation better or something.

An MRI is not the most pleasant thing to have done but it’s a great diagnostic tool and it doesn’t hurt.

I always describe MRI as very noisy and very boring! In fact, it is so boring that a fair percentage of people fall asleep (no kidding!).

Your son won’t notice what scan is being done when as they’ll almost certainly just run them one after the other without getting him out. As meme already said, head and orbital is head and eyes. They will scan both of these using a couple of different types of scan from different directions. Diffusion weighted is a newer type of scan that is good for detecting “active” lesions, ie lesions associated with a current attack. So, they will do a diffusion weighted scan of his head and eyes as well as the other types of scan. Diffusion weighted scans are beginning to replace the contrast scans that meme mentioned.

MRI is completely safe as long as we satisfy the screening questions (things like do you have a pacemaker? any shrapnel in your body? etc). It’s important not to have any loose metal on us because the scanner is actually a giant magnet so it’s not a good idea to have metal flying about.

Although the hole in the middle (the “bore”) seems too close for some people’s comfort, the scanner cannot move or fall in on someone.

The noise is just radio waves, but they are very loud so you have to protect your ears with either headphones or/and ear plugs. (The radio waves are used to generate the data that make the images.) Because the noise is very loud, it can make the bed move a bit, just like something sat next to very loud music coming through a big speaker. So your son should expect it to be very noisy and for the bed to vibrate. Different types of scan make different noises so one way to pass the time is to guess how many scans have been done and even what direction they are taking the images from because the noise gives it away!

Most people will have a sort of birdcage thing put over their head for a head scan (the “headcoil”). This helps to get really good data and has the added benefit of keeping people’s heads still which is very important.

So, all in all, very noisy and, since the most interesting thing to do while you’re in there is try and work out which direction the noise is going(!), very boring! But very important too.

Btw, you can pay for a copy of your scans on CD. My local hospital charges £18.50, but it varies. It’s pretty cool to get pictures of your brain - if you’re a geek like me at least :slight_smile:

Karen x

Thank you both for your informative replies, I will show them to my son and hopefully it will make him feel a bit less nervous. I will definitely ask for a copy of the scan for him to keep! Thanks again x

Reassured to know I’m not unusual in falling asleep having an MRI! My last one took two hours, full head and spine with and without contrast, couldn’t believe how long I was in there for but I did at one point fall asleep - I suddenly became aware of the technician asking me if I was ok and had I fallen asleep as apparently I stopped answering her!

I’ve done it too :slight_smile: Kx

I’m a bit claustrophobic so I don’t think I’d ever relax enough to sleep in an MRI. I had never realised how claustrophobic I was until my first MRI !!

But I can see how if enclosed spaces don’t bother you that it wouldn’t be an issue. Even with the panic I feel, I still get bored lol.