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Ultrasound imaging of the brain

alephneuro.com

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Re: Ultrasound imaging of the brain

#41

Post by virissimo »

thaw13579 wrote: post #38

Cool work and proof of concept, and very excited to see where this goes. However, I do think there is enough exaggeration and missing information here that it warrants some critical appraisal. What's really missing is a comparison and validation with any existing medical imaging tech. Whole brain, contrast-free neurovascular imaging is essentially solved with MRI, why not run a scan and compare? Ultrasound is of cour…

> MRIs are actually widely available in most cities at reasonable cost

Typical wait time for an MRI in Canada is 2 months.

Re: Ultrasound imaging of the brain

#42

Post by thaw13579 »

kyawzazaw wrote: post #39
thaw13579 wrote: post #38

Cool work and proof of concept, and very excited to see where this goes. However, I do think there is enough exaggeration and missing information here that it warrants some critical appraisal. What's really missing is a comparison and validation with any existing medical imaging tech. Whole brain, contrast-free neurovascular imaging is essentially solved with MRI, why not run a scan and compare? Ultrasound is of cour…

most cities where?

Here are OECD and WHO reports on regional availability of MRI:

https://www.oecd.org/en/publications/health-at-a-glance-2025...

https://www.who.int/data/gho/data/indicators/indicator-detai...

Africa, Central & South America are clearly underserved, perhaps a good opportunity for ultrasound and low-field MRI

Re: Ultrasound imaging of the brain

#43

Post by amluto »

nick238 wrote: post #25
Aurornis wrote: post #18

Earlier quoted context omitted.

Showing us a technique that is entirely reliant on sparseness and then saying they hope to employ it on something that isn’t sparse at all (blood cells) does feel misleading. I’m filing this in the category of technologies I wish could be true, but for which no plausible path to overcoming the obvious limitations has been provided.

From the bubble center plot, I'm guessing that the bubbles are separated on average about a few mm apart? Taking the other comment's guess at face value, you're going from about 2 mm to 20 um, so 2 orders of magnitude. Air (technically SF6 in the article) and water (RBC is close enough) have acoustic impedances that differ by 3.5 orders of magnitude. My assumptions here are * extremely generous* , i.e. favorable to t…

As another way to estimate this, here’s a data sheet for some microbubbles:

https://pdf.benchchem.com/1673/Application_Notes_and_Protoco...

So 1-5e8 bubbles per mL, and let’s suppose you inject 5mL. (I have no idea what the human dose is, but that’s what’s in this particular kit.)

You apparently have 5e9 or so RBCs per mL of blood:

https://en.wikipedia.org/wiki/Complete_blood_count

You have about 5L of blood, so that’s three orders of magnitude more volume than the contrast, and RBCs are 10x-50x as concentrated as the microbubbles in the syringe, so about 4 orders of magnitude concentration difference.

It’s basically changing this from a 0D problem to a 1D problem.

Re: Ultrasound imaging of the brain

#44

Post by thaw13579 »

switchbak wrote: post #40
thaw13579 wrote: post #38

Cool work and proof of concept, and very excited to see where this goes. However, I do think there is enough exaggeration and missing information here that it warrants some critical appraisal. What's really missing is a comparison and validation with any existing medical imaging tech. Whole brain, contrast-free neurovascular imaging is essentially solved with MRI, why not run a scan and compare? Ultrasound is of cour…

"MRIs are actually widely available in most cities at reasonable cost" - I live in one of those first-world countries, and our citizens regularly wait many months if not over a year to get a single MRI scan. Yes, it's not just an issue of the MRI but the entire medical system, but the point still stands. Were there machines that were one or more orders of magnitude cheaper and simpler to run - I think we would see a…

I completely agree that's an issue, although more of an economic / public health policy issue than a technical one. There are low field MRI systems, such as the one made by Hyperfine that are, like you say, an order of magnitude cheaper and simpler to run. We should have these everywhere, IMO

https://www.hyperfinemri.com/

Re: Ultrasound imaging of the brain

#45

Post by fragmede »

iamleppert wrote: post #29

Every few years one of these ultrasound companies comes around and promising to revolutionize medical imaging and nothing ever comes of it. Anyone remember https://www.openwater.health ? The same ideas are in a perpetual state of being reinvented and part of me thinks its just a hustle for the MIT Media Lab/Stanford Imaging grads to give them something to do. The tell is "super resolution", "brain computer interface"…

but technology is getting better all the time what doesn't work because they only have one Tesla, well shit, let's try it with 100.

Re: Ultrasound imaging of the brain

#46

Post by dwroberts »

qgin wrote: post #9
w4yai wrote: post #5

It feels like ultrasound is solving everything for the last week.

There were a lot of people who declared very loudly last week during the Midjourney discourse that this was an impossible use of ultrasound.

Is Aleph an established entity with a track record that should lead us to trust this at face value? I couldn’t find any info on them and the site seems new

Re: Ultrasound imaging of the brain

#47

Post by thaw13579 »

virissimo wrote: post #41
thaw13579 wrote: post #38

Cool work and proof of concept, and very excited to see where this goes. However, I do think there is enough exaggeration and missing information here that it warrants some critical appraisal. What's really missing is a comparison and validation with any existing medical imaging tech. Whole brain, contrast-free neurovascular imaging is essentially solved with MRI, why not run a scan and compare? Ultrasound is of cour…

> MRIs are actually widely available in most cities at reasonable cost Typical wait time for an MRI in Canada is 2 months.

Yes, that is a economic & public health policy problem that really needs to be solved. We can look to Japan as example of what's possible, they have invested in nearly twice the number of scanners per capita of Canada, and they can get same-day MRIs for $50, roughly speaking.

Re: Ultrasound imaging of the brain

#48

Post by dwroberts »

dwroberts wrote: post #46
qgin wrote: post #9

Earlier quoted context omitted.

There were a lot of people who declared very loudly last week during the Midjourney discourse that this was an impossible use of ultrasound.

Is Aleph an established entity with a track record that should lead us to trust this at face value? I couldn’t find any info on them and the site seems new

Oof did a bit more digging: https://x.com/_marleyx/status/2070260772635312598

> None of us were ultrasound scientists before this. We worked backwards from a desire for brain interfaces and taught ourselves physics, ultrasound, electromagnetism.

Not to say it’s not interesting or neat, but the Silicon Valley approach to solving medical issues doesn’t have a good track record, let’s put it that way

Re: Ultrasound imaging of the brain

#49

Post by fernly »

wildylion wrote: post #34

Who could've thought that injecting SF6 into blood vessels is actually safe enough to be FDA-approved... interesting.

Per Wikipedia, it "is a colorless, odorless, non-flammable, and non-toxic gas."

When used as a contrast agent for ultrasound, it "has been used to examine the vascularity of tumours" -- which would be similar to its use in the OP. Then "[i]t remains visible in the blood for 3 to 8 minutes, and is exhaled by the lungs."

So -- not collected and excreted by the liver, as I at first thought.

Re: Ultrasound imaging of the brain

#50

Post by scratcheee »

thaw13579 wrote: post #44
switchbak wrote: post #40

Earlier quoted context omitted.

"MRIs are actually widely available in most cities at reasonable cost" - I live in one of those first-world countries, and our citizens regularly wait many months if not over a year to get a single MRI scan. Yes, it's not just an issue of the MRI but the entire medical system, but the point still stands. Were there machines that were one or more orders of magnitude cheaper and simpler to run - I think we would see a…

I completely agree that's an issue, although more of an economic / public health policy issue than a technical one. There are low field MRI systems, such as the one made by Hyperfine that are, like you say, an order of magnitude cheaper and simpler to run. We should have these everywhere, IMO https://www.hyperfinemri.com/

MRIs are fundamentally expensive. Yes we can bring the price down a bit, and we can set more money aside for them, but they’ll always be limited by their price.

Even if this technique is much worse (I can certainly believe it is) the price might allow uses that would never be practical with MRI even with the best financial support. For example, ultrasound might be viable for use in GPs or small medical facilities which could never dream of justifying an MRI machine.

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