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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

#71

Post by lostlogin »

an1sotropy wrote: post #55
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…

I think it is amazing that they're getting decent ADC maps - diffusion imaging is fundamentally about measuring how much the image gets dimmer (due to diffusion sensitizing gradients), so it's always running up against SNR limits. This is so darn cool.

It really is.

For some reason it reminded me of the crazy project where some team used the earths field as the static field and just added gradients and the RF stuff. I can’t find the article I remember but this project looks similar and scans a capsicum rather than an apple.

https://www.researchgate.net/publication/6956005_A_practical...

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

#72

Post by TheMagicHorsey »

lostlogin wrote: post #67
mr337 wrote: post #63

Earlier quoted context omitted.

Some of the automotive stuff is really great to get started. Was working on an agriculture robot and needed a good way to detect a level of something. In short a IP65+ hall effect sensor that can get wet and dirt no problem. The solution was a $12 ride sensor from a Cadillac SUV of some type. Worked perfect!

I had a friend automating a production line and he needed to detect the level of peanut butter in a vat. He settled on an ultrasonic device as basically anything else ended up caked in peanut butter. It was an impressive setup, all done in Arduino.

I wonder if its practical to DIY your own production line automation today with Arduino. Like if I had a simple product, could I buy stuff off the shelf and integrate it myself in my garage and end up with a little mini-factory? Exciting to think about.

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

#73

Post by lostlogin »

mattkrause wrote: post #61
a-dub wrote: post #5

woah. woah. woah. hold on a second here... are we comfortable enough with understanding all of the behavior of deep learning models to where we can confidently put them in the pipeline for diagnostic clinical imaging? i'm okay with using them for image analysis, but denoising and other image production tasks seems dangerous. how do you know what you're looking at is real as opposed to something that just looks convin…

Amen! I have seen an alarming number of talks where someone proposes to algorithmically add Gado contrast or turn a T1 into a T2 image. In a few very specific contexts, this makes sense (e.g., aligning a T1 taken in one session with a T2 taken in another). Otherwise though, it seems dangerous to mistake a "real" image with the expected image given another one.

If reducing gadolinium dose is the aim, a more prompt following of the literature, radiologist request (rather than surgeon demand) and weight based dosing would drastically reduce dosage. A moaning radiographer, what a surprise!

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

#74

Post by doctoring »

littlestymaar wrote: post #62
AnimalMuppet wrote: post #37

Earlier quoted context omitted.

But if the answer is "yes", the next question is "do I also have pinhead-sized metastases, and if so, where?"

Isn't this question answered by a PET scan and not MRI ?

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 metastasis.

Also, in the brain, PET scans (at least the most common, FDG, which is based on glucose) are extremely limited in utility because of the baseline high glucose metabolism of the brain, which makes it hard to distinguish from the metabolic activity of a tumor.

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

#75

Post by TaylorAlexander »

TheMagicHorsey wrote: post #72
lostlogin wrote: post #67

Earlier quoted context omitted.

I had a friend automating a production line and he needed to detect the level of peanut butter in a vat. He settled on an ultrasonic device as basically anything else ended up caked in peanut butter. It was an impressive setup, all done in Arduino.

I wonder if its practical to DIY your own production line automation today with Arduino. Like if I had a simple product, could I buy stuff off the shelf and integrate it myself in my garage and end up with a little mini-factory? Exciting to think about.

I obsess over this concept. I am a robotics engineer and my dream is local manufacturing with small DIY machines. But it's a lot of work! When I have a little more time I want to teach community robotics classes and build machines that makes shoes and hot food and other important goods, designed and built as a community. I designed a cheap large format laser cutter [1][2] and now I am designing shoes that can be made with a 3D printer, the laser cutter, a sewing machine, and some basic tools. [3]

[1] https://twitter.com/TLAlexander/status/1480332181285212160

[2] https://github.com/tlalexander/large_format_laser_cutter

[3] https://twitter.com/TLAlexander/status/1489519692712538113

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

#77

Post by endymi0n »

Apart from the potentially massive significance to low-income countries and health costs, does someone has a good grasp on the applicability of the algorithmical advances towards classic MRI?

My current gut feeling is like: If 0.055 Tesla can create this kind of image quality, what could we possibly expect at 1.5 or more?

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

#78

Post by qrian »

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.

> First, these scanners rely on complex superconducting electromagnet/cryogenics designs and ever increasingly powerful electronics (including gradient and radiofrequency power systems) for fast imaging and/or advanced imaging features like brain functional MRI and diffusion tractography, yet routine clinical uses only necessitate a small portion of these imaging protocols.

I guess this implies not?

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

#79

Post by WalterSear »

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…

I prefer to think of that study as evidence for life after death.

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

#80

Post by lostlogin »

TheMagicHorsey wrote: post #72
lostlogin wrote: post #67

Earlier quoted context omitted.

I had a friend automating a production line and he needed to detect the level of peanut butter in a vat. He settled on an ultrasonic device as basically anything else ended up caked in peanut butter. It was an impressive setup, all done in Arduino.

I wonder if its practical to DIY your own production line automation today with Arduino. Like if I had a simple product, could I buy stuff off the shelf and integrate it myself in my garage and end up with a little mini-factory? Exciting to think about.

The person I was describing runs a food production line and has modified various bits of equipment for speed, efficiency, safety and ease of use. They have got great results. They have no formal training, have no software background and basically go to https://www.dfrobot.com and get what they need, then hack.
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