3T MRI Clarification

[Quixotic1]

Several times recently I have seen comments that indicate something I regret.  I have apparently given the impression that an MRI done on a machine with a strength lower than 3T is useless.  This is not true.  For the vast majority of people with MS, the diagnosis was made with a machine of 1.5T or lesser strength.  Normally a 1.5T is perfectly good and is always an okay place to start when the doctor suspects MS in someone.  I don't want anyone to feel that if they have gotten their first MRI on a lower strength machine, that they have wasted their time and money.

When the diagnosis is elusive and the clinical picture is very suggestive of MS, then I believe that a person should try to get the next films on the highest strength MRI available.  I always suggest it as one of the strategies to get out of Limbo.  The studies do show that a 3T shows more MS lesions than a 1.5T.  This is because the very small lesions may not show at all on a 1.5T, but may be very clear on the higher machine.

Going along with this is that lesions in the brainstem and spinal cord are more difficult to image.  The 3T is superior for this purpose.  So, if a person has symptoms that are very suggestive of spinal cord disease like:

Hyperactive reflexes
L'Hermittes sign
mild spasticity
urinary dysfunction

it would make sense to use the highest power machine possible for the spinal MRI.  If the first MRIs do not show anything, then it would make sense to do repeat MRI on a higher power machine.

But, if the person only has access to something lower than a 3T - and this is lots of people - then do NOT feel bad going ahead and getting them done.  Most people with MS will have lesions that show up - even on a 1T.

Again, it is just the people whose diagnosis has eluded the doctors who really should push for the higher power machines.  If all things are equal, then it also would make sense to get the first films on the highest power that is available, but if a machine is not available or if insurance won't pay, then get the imaging done where you can.

For the purposes of MS, though, the lowest power that is acceptable is a 1T.

Did I garble this or do you see what I am trying to say?

Quix

[Lulu54]

you can simply ask the tech or nurse who is running your test "what Tesla strength is this machine?"  It should also say on your old films but it might be written in code.  

the easist way to find out might be to call the place where the test was done, tell them what year it was done, and ask them what Tesla strength their machine was back then.  They should know the answer to that pop-quiz!  

One thing you want to be sure to do is ask your neuro to have this done w/contrast so they get a better image if anything is active. Stay in touch, Lulu

Ps you might want to start this as a new post - you will get lots of advice that way rather than it being at the end of this lengthy discusion.

[GrannyJo6]

I see my neuro next week and I think I am due for another MRI.  What do I ask to know what strength the machine is? This is new to me, so bear with me! I actually have all the films from last time in my possession per my neuro's wishes. Would it say on them anywhere? Thanks!

[ShadowsSister]

Hi there, I don't know what MRI machine was used this was back in Jan. of 1986, but it was strong enough to show the three major lesions and "numinous minor one, these were in the brain, in 1987 they discovered the spinal lesions... Guess I was Lucky, if you want to call it that... It seems to me that since "They" have gotten more MS Drugs on the market it is harder to be given a diagnoses.. I don't quite understand this...
I can no longer have MRI's my body refuses to cooperate and I can't be sedated because the "full body" spasms get so much worse...

[Quixotic1]

I don't know about "any other neurological problem" but it is worthless, useless, for the diagnosis of MS - UNLESS it did show the lesions.  In other words, if it was negative for T2 lesions we don't know anything.

Quix

[julia111]

Thanks .....

So, I can feel pretty confident that my one and only MRI of Brain done on ....

..... Open .25 Tesla Machine Without Contrast .......

really cannot be used to "rule out" MS or any other Neurological problem except Stroke or Tumor?

Julia

[Wobbly]

that make sense to me... and will remeber that next time...thanks Quix

wobbly
LL

[Lulu54]

I'm going to hold out for the 7T for my next MRI - I want to see the insides of everything too!  

Ok, I'm just kidding.  My MRI's were done locally on a 1.5  Tesla machine  - my lesions certainly were visible enough to help clinch my diagnosis.  My repeat MRI that is scheduled at OSU in December will be done on a 3T I believe.  It will be interesting to see how much more is going on with my brain.

It's often not practical or possible to demand being screened on something that isn't readily available or financially within reach.  Everyone has to keep it in perspective and remember that the MRI alone won't clinch a dx.

My two cents,
Lulu

[sllowe]

I'm not remembering the 1.5 disrespected here, but the .07 or something like that, yea, I remember us being all over it, especially when looking for MS. You've explained it very well Doc Q, always.

Do we know if the 3T is approved by the FDA yet? When I brought that up to the Chief Tech at the last place, he said it was not approved.  Knowing it is used regardless, just curious if that is the hold up for some facilities...juuuust a' wondering....

-Shell

[goofysmom1]

I thought you explained it very well - you do a very good job making some of the technical stuff easy to understand. Thank you!

Chrisy

[Sunnytoday]

Quix, you did a great job of explaing this, much clearer than the mess I made of it the other day when I tried to explain it to my parents.... in my case it was better to try the higher MRI becuase the lower ones were showing up problems but Dr. K wanted a clearer picture, and the MRI at his facility is a 3T so, he was like "I want you to use this one, it's fancy and it works!" He made me laugh, but helped me understand what you and he were trying to say! ;)

Thanks for all the time and effort you put in here Quix, posts such as this give many of us clear valuable information that is often confusing elswhere!
~Sunnytoday~

[jensequitur]

Sounds good to me!  I was diagnosed with a 1.5 Tesla MRI.