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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

#111

Post by morcheeba »

asiachick wrote: post #105
cute_boi wrote: post #21

Earlier quoted context omitted.

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.…

I worked for a medical company that did RF tumor ablation. In Japan we sold a machine that cooked small tumors as an out-patient procedure, because their easy MRIs would spot them early. In the US, we sell more complicated machines that work on bigger tumors because we find them later here - when they get too big, you have to be very careful not to damage surrounding tissue.

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

#112

Post by prefrontal »

ortusdux wrote: post #19
l33tman wrote: post #8

Earlier quoted context omitted.

This project doesn't use AI to improve the image, they use it to estimate the EMI noise from the surroundings. So they're not "filling in the gaps" in the actual resulting 3D voxel volume with fantasy voxels (which I hope will never ever fly in a clinical setting). "To tackle the EMI signals from the external environments and internal low-cost electronics during scanning, we developed a deep learning driven EMI cance…

I'm glad that this is the approach that they are taking. There have been plenty of issues with fMRI false positives due to misconfigured software. The most famous would probably be the IG Nobel winning study that detected brain activity in a store-bought salmon: https://blogs.scientificamerican.com/scicurious-brain/ignobe... https://www.discovermagazine.com/mind/fmri-gets-slap-in-the-... Later studies called into que…

Thanks for the kind words. I am the first author of the "Neural correlates of interspecies perspective taking in the post-mortem Atlantic Salmon: An argument for multiple comparisons correction" paper. Happy to take any questions here. A link to the original poster: http://prefrontal.org/files/posters/Bennett-Salmon-2009.pdf

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

#113

Post by lostlogin »

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.

I’ve spent a long time around scanners and re-read this book before helping students. It’s remarkable easy to lose track of the fundamentals, though maybe that’s just me.

The whole book is available for free as a download. MRI Made Easy (… Well almost). https://rads.web.unc.edu/wp-content/uploads/sites/12234/2018...

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

#114

Post by lostlogin »

rasmus1610 wrote: post #107
mwint wrote: post #102

Earlier quoted context omitted.

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

How funny, you just beat my comment. A link to it.

https://rads.web.unc.edu/wp-content/uploads/sites/12234/2018...

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

#115

Post by lostlogin »

fluidcruft wrote: post #100
doctoring wrote: post #74

Earlier quoted context omitted.

Usually not! PET scans are limited in resolution when you get down to the sub-5 mm or so range due to scanner technology and fundamental limits of the physics of positron/electron annihilation & photon emission. A typical MRI (i.e. alas, not what this article is describing) can usually resolve something at that size and identify characteristics like diffusion restriction or contrast enhancement which can confirm meta…

The flip-side of that is that PET is vastly multiple orders of magnitude far more sensitive than MRI. So while PET may not be able to localize as well as MRI, it can detect smaller things if the targeting of the radioisotope is good.

Maybe the state of play has changed, as we scan for this indication in MR, not PET.

Have you a link to something as my understanding is that small lesions are better found with MR?

Or is this a rule that applies to high end research work and hasn’t hit clinical practice yet? Maybe a limitation of the isotopes used clinically?

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

#116

Post by ska »

lostlogin wrote: post #97
ska wrote: post #42

Earlier quoted context omitted.

The up front cost is only one part of the story. Siting a conventional MRI is pretty expensive (often requires a new build 6 figures for sure) and operation costs can run up to even 5 fig/month for powerful ones. They could probably get one of these out the door for approx 100k. Clinical scanners are typically 10x+ that. Siting cost would be next to nothing, and operating costs low too.

This is a good comment and still underplays the cost of MRI. Getting a reasonable 3T setup going will be a lot more than US$1 million. Running costs are very high, with a scanner lifetime service contract being somewhere between 50% and 100% the original cost of the MRI scanner. Additionally, the scanner cost is only part the price. There is the Faraday cage, chilling, room setup, building strengthening, scanner inst…

I was intentionally handwaving but above is about right in orders of magnitude, i just rolled things up.

Staffing is an interesting one (which I ignored, but good point you can't really) - lots of potential deployments of a small machine like this probably don't look anything like a US standard imaging suite, and aren't going to be staffed the same way. If you run all the numbers in detail you get big variations here, depending on set up.

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

#117

Post by sfink »

robwwilliams wrote: post #56
carbocation wrote: post #54

This sort of technology offers a lot of value for understanding human health in the future. Right now, we (physicians) discourage people from getting tested outside of guidelines because we don't know what to do with incidental findings. But you could imagine that as a society, we would like to detect and understand these things, rather than just remain ignorant to them. Inexpensive technology like this could be perf…

And perfect for very high false discovery rates and unnecessary downstream diagnostic burden and iatrogenic errors. Rather see a focus on new magnet technologies to reduce cost without loss if already marginal clinical MRI resolution.

> And perfect for very high false discovery rates and unnecessary downstream diagnostic burden and iatrogenic errors.

...which is exactly why the comment you're replying to says that physicians discourage them. That's missing the point; noisier devices are indeed not going to be great at improving the existing applications. But there's a whole world of other possibilities out there as long you don't try to substitute questionable data for good. Like monitoring over time, or between-patients studies where you get additional significance from large numbers, or even just fishing expeditions where you see what the cheaper and more deployable stuff is capable of. Not everything needs the best and only the best.

> Rather see a focus on new magnet technologies to reduce cost without loss if already marginal clinical MRI resolution.

Why not both? The work required is going to be pretty different.

And chaining them together is a time-honored technique: use the quick cheap thing to detect reasons to dig in with the fancy stuff. Your base rate may be low, but if the quick check is negative then the adjusted probability might drop it below some other cause that you'd be better off looking into.

Data is good, just don't fuck it up.

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

#118

Post by _qua »

saulrh wrote: post #109

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.

People with metal implants and bullets can often still have MRIs with some additional screening/safety measures. There may be advantages to operating under live MRI guidance but I'm not aware of any research on that. Even with low fields, you still would get artifact from having metal near your target of imaging.

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

#119

Post by BizarroLand »

prefrontal wrote: post #112
ortusdux wrote: post #19

Earlier quoted context omitted.

I'm glad that this is the approach that they are taking. There have been plenty of issues with fMRI false positives due to misconfigured software. The most famous would probably be the IG Nobel winning study that detected brain activity in a store-bought salmon: https://blogs.scientificamerican.com/scicurious-brain/ignobe... https://www.discovermagazine.com/mind/fmri-gets-slap-in-the-... Later studies called into que…

Thanks for the kind words. I am the first author of the "Neural correlates of interspecies perspective taking in the post-mortem Atlantic Salmon: An argument for multiple comparisons correction" paper. Happy to take any questions here. A link to the original poster: http://prefrontal.org/files/posters/Bennett-Salmon-2009.pdf

It would be nice if the cost of an MRI was so low you would typically get a cheap one as part of your yearly physical and if anything popped up they could do it again in an expensive, high powered one to verify.

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

#120

Post by heartbeats »

lostlogin wrote: post #97
ska wrote: post #42

Earlier quoted context omitted.

The up front cost is only one part of the story. Siting a conventional MRI is pretty expensive (often requires a new build 6 figures for sure) and operation costs can run up to even 5 fig/month for powerful ones. They could probably get one of these out the door for approx 100k. Clinical scanners are typically 10x+ that. Siting cost would be next to nothing, and operating costs low too.

This is a good comment and still underplays the cost of MRI. Getting a reasonable 3T setup going will be a lot more than US$1 million. Running costs are very high, with a scanner lifetime service contract being somewhere between 50% and 100% the original cost of the MRI scanner. Additionally, the scanner cost is only part the price. There is the Faraday cage, chilling, room setup, building strengthening, scanner inst…

Why so expensive? Couldn't you just site it way out in the boonies? If you put it on a giant purpose-built concrete cube, it seems like most of this stuff becomes cheaper.
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