Thoughts on 1.5t vs 3t MRI scanner

Hi guys,

i just had an MRI in a mobile MRI van at hospital today. I asked what strength the machine was as I’m desperate for them to find another lesion for my clinical diagnosis following transverse myelitis and lesions in spine, brain and positive for obands.

they told me it was a 1.5t but I know that the hospital def has a 3t as well as several 1.5ts.

its so important to me that I get this diagnosis because I was started on plegridy a few months ago but had a mild allergic reaction to it - hence they won’t let me continue with any interferon based drug and have decided to do a follow up MRI to try and locate new damage that would make me eligible for different treatment (I’m really hoping for lemtrada)

So based on this, and how crucial it is that they find something, I don’t understand why they used a 1.5t instead of the 3t?? Especially because most of my lesions are in my spine and it’s this area that I understand is better scanned with a 3t.

i find this whole “wait and see” approach to ms treatment/diagnosis so frustrating!!! Surely by the time they “see” something it may be too late to reverse damage.

so it would be great if any of you guys had an opinion on how much better 3t is compared to 1.5t?

Thanks so much for reading



I’m a diagnosed person - I’ve NEVER been scanned on higher than a 1.5T scanner, which is still the norm in most places.

In my case, it spotted the initial lesions at the very first scan, AND new ones six months later, which allowed my neuro to confirm the diagnosis.

So, I know you are not going to like this phrase, but I think it’s a case of “wait and see” what it finds, before jumping to the conclusion the scanner wasn’t strong enough.

The other thing that occurs to me is that unless your initial scan was on a 3T scanner, having one now would not be valid for comparison purposes, because you wouldn’t be comparing like with like.

You would expect the higher powered scanner to find more, therefore it wouldn’t be safe to conclude any additional findings were “new damage”, as they could be things that were there last time, but the lower powered scanner couldn’t see.

So as the whole point is before and after comparison, to see what (if anything) has changed, I think it’s important to stick with the same measurement method each time. If it’s a different powered scanner, any evidence of change will be ambiguous, and not very reliable.


1 Like

Hmmmm yes - that’s a very good point. Thanks Tina. I feel a little less enraged now… I think I just wind myself up so much at the moment thinking that if things were done differently I would be diagnosed…

i can’t stand this waiting game, it’s so frustrating. Especially when past MRIs since my transverse myelitis have said things like “subtle persistence of lesions” and “areas of hyperintensity” - surely that’s enough evidence of dissemination in time??

oh pass the wine…

thanks for your reply Tina xx

I suggest you read who has a PHD in MRI and explains knowledgeably the scanners; brain and other very interesting information.


Thanks very much George - that’s great x