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A low-cost and shielding-free ultra-low-field brain MRI scanner

nature.com

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Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#101

Post by innolitics »

TheJoeMan wrote: post #32
lostlogin wrote: post #4

The images are better that I expected. The ‘FLAIR like’ image is not particularly FLAIR like. FLAIR are nicer to look at when fat saturated (not everyone agrees with that), but that’s probably not feasible at that field strength and adding scan time would be a problem on these long sequences. Voxel sizes of 2x2x10 are pretty terrible resolution, but if the alternative is nothing, I guess that’s ok. The static field i…

You know, sometimes all you need is “do I have a baseball sized tumor or not”.

That's absolutely true. We work with a lot of technical founders who are turning their research into a diagnostic medical devices. One of the first questions we always ask is: how will the information produced by your device help clinical decision making? More data is _nice_ but if it doesn't alter the course of treatment, it's pointless. Sometimes it's okay if the doctor doesn't know if the problem is A or B if the treatment for A and B is the same.

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#102

Post by mwint »

fluidcruft wrote: post #95
queuebert wrote: post #70

Earlier quoted context omitted.

Or a massive brain hemorrhage.

That's generally been the challenge with these super low-field scanners--they can't get T2*/susceptibility that's anywhere close to useful (yet?).

Reading the terminology being thrown around here, where could I go to get a basic understanding of what you’ll are talking about?

It sounds like different modes of taking (or interpreting/visualizing?) an MRI.

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#103

Post by theptip »

At $20k estimated cost, you are getting into territory where the TAM of non-medical uses may be higher.

Sports physio / trainers would kill to be able to do regular MRI on their athletes. Being able to do pre/post workout imaging, and the kind of training programs this level of visibility would unlock, are quite exciting.

Assuming you can generalize from brain to whole-body, I think you could sell one of these to every major sports team in the country, and making it a non-medical device (ie skipping the FDA) would let you iterate much faster. A couple more halvings in price and this is accessible to every sports physio office and gym in the country.

Very cool!

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#104

Post by hwillis »

qrian wrote: post #76

Can this also do fMRI? I'm already trying to build DIY fnirs machine for cogsci research but if this does fMRI too I might build this one too.

> We have experimentally estimated in our preliminary study that the apparent T1/T2 values for gray matter and white matter were approximately 330/110 ms and 260/100 ms at 0.055 T (vs. 1300/110 ms and 830/80 ms at 3 T51) while CSF maintains long T1 (>1500 ms) and T2 (>1000 ms).

That's not particularly different from normal MRIs, and the achieved resolution is not that much worse than normal MRIs. The scans have lower contrast (and repeated/longer scans is one way to improve that) and using for functional imaging will make that worse, but honestly it doesn't seem to have suffered very much at all.

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#105

Post by asiachick »

cute_boi wrote: post #21
egocodedinsol wrote: post #13

“There are approximately seven scanners per million inhabitants and over 90% are concentrated in high-income countries. We describe an ultra-low-field brain MRI scanner that operates using a standard AC power outlet and is low cost to build.” This is fantastic. What a sentence to get to write.

Yea, the way they turned the bleak situation into something sanguine is fascinating. I still remember how expensive is MRI. I used to earn like $150 usd and the cost was around $200 usd. I hope such inequality shall perish in the future, so people can at least get proper treatment.

I'm curious what makes them expensive. In Japan they are basically free (covered by national insurance for which the price is low). I believe at one point Japan had the most MRI machines per capita. I think the government just decided they were worth while and got a bunch where as in the USA they were seen as a money source and they generally charge $1k to $10k ?!?!?!

I'd love for the expensive ones to be disrupted. The dream is we get some attachment for our smart phones and turn them into Tricorders.

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#106

Post by VikingCoder »

lostlogin wrote: post #86
VikingCoder wrote: post #26

Earlier quoted context omitted.

That's a valid risk. You're asking a cost-benefit question. The cost of an invalid diagnosis is indeed high. The cost of no diagnosis at all is also high. This device will not replace the MR at your local hospital. It will be the first MR device in hospitals that have never had one before.

Veterinary MRI may be another application.

Good point. Cargo inspection? Luggage inspection? I dunno.

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#107

Post by rasmus1610 »

mwint wrote: post #102
fluidcruft wrote: post #95

Earlier quoted context omitted.

That's generally been the challenge with these super low-field scanners--they can't get T2*/susceptibility that's anywhere close to useful (yet?).

Reading the terminology being thrown around here, where could I go to get a basic understanding of what you’ll are talking about? It sounds like different modes of taking (or interpreting/visualizing?) an MRI.

These are different MRI sequences that are weighted differently to produce a specific contrast that show different characteristics of the tissue that is imaged.

I really liked ‚MRI made easy‘ as an introduction to MRI physics. Just google it, it’s a free Book

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#108

Post by lostlogin »

VikingCoder wrote: post #106
lostlogin wrote: post #86

Earlier quoted context omitted.

Veterinary MRI may be another application.

Good point. Cargo inspection? Luggage inspection? I dunno.

There are a lot of applications that are surprising. I’ve scanned for salmon farmers (is that the term?) who want to check they are breeding good fish and are looking at spine alignment.

I’ve scanned logs for forestry managers who want to look at something in their trees.

I’ve scanned old hearts that have been sitting in formalin for decades.

All are probably better at higher field strength but maybe some of that can be compensated for by scanning for longer? A log isn’t going to move, and a dead fish scan is likely only limited by the time it takes for it to rot.

I’d be scared of scanning unknown things, it might be a low field MRI, but it’s still a big magnet.

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#109

Post by saulrh »

Being able to use this around metal is also huge. It means you can use it on patients with metal implants or bullets in them, to guide surgery in real-time, in the surgical suite, at the same time as other medical instruments, at the patient's bedside instead of in a dedicated room that you have to transport the patient to, etc.

Re: A low-cost and shielding-free ultra-low-field brain MRI scanner

#110

Post by fluidcruft »

mwint wrote: post #102
fluidcruft wrote: post #95

Earlier quoted context omitted.

That's generally been the challenge with these super low-field scanners--they can't get T2*/susceptibility that's anywhere close to useful (yet?).

Reading the terminology being thrown around here, where could I go to get a basic understanding of what you’ll are talking about? It sounds like different modes of taking (or interpreting/visualizing?) an MRI.

(vastly simplified) MRI basically functions on two fundamental mechanisms--"spin echo" and "gradient echo". Spin echo signal is described by T1 and T2. Gradient echo signal is described by T1 and T2*. The difference between T2 and T2* relate to local magnetic properties of the tissue which is called "susceptibility". Blood contains iron so its presence alters T2* and this is exploited clinically. A good example of T2* imaging used clinically is susceptibility-weighted imaging (SWI).

T2* effects increase with higher MRI main field strength. From what I can tell so far these ultra low-field scanners have to rely on spin echoes.

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