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Ultrasound imaging of the brain

alephneuro.com

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Re: Ultrasound imaging of the brain

#31

Post by Aurornis »

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…

> From the bubble center plot, I'm guessing that the bubbles are separated on average about a few mm apart?

The page is vague so I can't tell. I think the images they're showing are actually a composite of many bubbles tracked through the vasculature.

They say this:

> As bubbles flow through the vasculature, we accumulate millions of these positions and stack them into a single image with detail finer than the wavelength.

And the rendering showing the bubble centers they're tracking only shows a few small points moving at a time.

I think that the amazing animation they produced at the top is actually a composite of many different trackings, not an actual representation of what they capture in real-time.

Re: Ultrasound imaging of the brain

#35

Post by brendoelfrendo »

paytonjjones wrote: post #20
frangonf wrote: post #15

Meta is also going at it [0], which inevitably makes me ponder some orwellian questions for the near future: If I bring my pet mouse to the cinema and my friend scans the movie back using his apple ifmri does the DRM still holds or will the mouses be DRM locked? Will my iris suffice for booting my computer or would I need to press accept all brainwave cookies? Can I email my local Flock representative to install a ne…

The current state of the world, where we have insane and ubiquitous surveillance tech but our packages are nevertheless being constantly stolen (with the thieves "caught" under said surveillance but with no one bothering to enforce it), is certainly an interesting one. I wonder what Orwell would have thought.

The surveillance is not about protecting you or your property; I'd argue it never has been. It's about protecting those in power and entrenching the power they wield.

Re: Ultrasound imaging of the brain

#36

Post by pedalpete »

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"…

It doesn't work until it does.

The same thing has been said about robotics, AI, space travel, etc. etc.

I'm not saying this is the way, and I have significant questions of understanding thought based on reading brain activity, but I wouldn't put down the entire ultrasound field.

Re: Ultrasound imaging of the brain

#37

Post by Preseason8448 »

wildylion wrote: post #34

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

Contrast-enhanced ultrasound (CEUS) with microbubbles has been around clinically for 20+ years. There are many contrast-agent manufacturers, e.g. Bracco (SonoVue/Lumason) or GE Healthcare (Optison). Safety-wise it's probably better than CT iodinated contrast or gadolinium MRI agents, and it's pretty well-established at this point.

Re: Ultrasound imaging of the brain

#38

Post by thaw13579 »

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 course portable and less expensive, but MRIs are actually widely available in most cities at reasonable cost for medical workflows, and low-field brain MRI is addressing the portability and cost issues to some extent. I guess they are pitching this as a wearable "telepathy" device, which I think appropriately differentiates their product, but of course, this wording also invokes a framing that "you won't / don't need to know how it works," which invites skepticism and a higher bar for validation in my view.

Re: Ultrasound imaging of the brain

#39

Post by kyawzazaw »

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?

Re: Ultrasound imaging of the brain

#40

Post by switchbak »

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 marked increase in availability.

I agree on your ground-truth desire, and I would hope they've done a lot of that to validate what we see here.

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