
How a $10 microchip turns 2-D ultrasound machines to 3-D imaging devices - stmw
https://techxplore.com/news/2017-10-microchip-d-ultrasound-machines-imaging.html
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plekter
I wrote my master's on doing the reconstruction a few years ago. On my shoddy
10 year old laptop GPU I could reconstruct a 3D volume from 800-ish slices in
about a second - depending on interpolation - so on modern hardware (or even
mobile hardware) I expect this to be doable in real time.

I do wonder about the spatial precision though, we used optical tracking back
in my thesis, and that was already noisy. There are techniques using speckle
patterns to help with the registration - but that seems like a tough issue to
solve. Either way, this is a cool idea and nice tech!

e: Oh, looks like it's orientation only - you'll need a steady hand making the
sweep then, since I suppose you can't move the position of the probe, just
it's rotation

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biomech
What's the output look like ? Is it comparable to MRI?

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plekter
It looks nowhere as good as MRI - but has the advantage of being very quick to
do. MRI will also image different things (depending on settings). US will show
you interfaces between different kinds of tissue (that's where you reflect
part of the US beam - echo!), but MRI has a million settings - and will
fundamentally show you water at different densities. What that means in
practice depends completely on the acquisition sequence.

The use case in my thesis went something like this

1\. Do MRI - use this to plan surgery and to navigate while in surgery 2\.
Once the patient is on the table, register the MRI image to the physical
location of the patient. 3\. With various 3d tracked tools, you can then
"point" at things in the real world, and have it show up on the MRI image. 4\.
As you are performing the surgical operation, you want to check "how does it
look now?" \- and that's where the tracked US probe comes in.

The use case outlined above isn't cost-sensitive, but time-sensitive. Getting
an US image takes seconds and can be done mid-operation. Another point is that
3D probes are quite big and clunky - and for AVM-type operations where you
crack the skull open, you want to keep that hole as small as possible. Phased
US sensors + reconstruction then gives you 3D images with a very small sensor
footprint. Another point is that 2D probes have higher resolution, so at least
the XY plane looks much better this way.

e: there are some pictures in my thesis:
[https://brage.bibsys.no/xmlui/handle/11250/253675](https://brage.bibsys.no/xmlui/handle/11250/253675)
The system we used/were developing:
[https://link.springer.com/article/10.1007/s11548-015-1292-0](https://link.springer.com/article/10.1007/s11548-015-1292-0)

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agumonkey
Allow to self cross post
[https://news.ycombinator.com/item?id=15590160](https://news.ycombinator.com/item?id=15590160)

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j_s
Thanks, I had missed that whole discussion (Butterfly iQ – A cheap handheld
ultrasound tool with AI smarts inside) which was very related and useful!

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afinlayson
This is remarkable, the data we could get from this would also be useful with
machine learning to detect abnormalities sooner. An excellent use of adapting
2 cheap technologies to bring down costs.

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tonysdg
3 cheap technologies:

> With the game console's ability to accurately track the exact position of
> the controller, he wondered, why not just duct-tape the controller to an
> ultrasound probe?

Never forget the duct-tape! ;)

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iokevins
This article claims future ultrasound equipment savings of ~80%: USD$250,000
(3D) vs. USD$50,000 (2D-modified).

From the perspective of patients and medical administrators, the upside seems
clear.

For (at least one?) ultrasound equipment manufacturer, this seems to imply
they don't make as much profit on the likely high-margin 3D models. Curious
how they and the industry responds.

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tyingq
That's pretty cool. The chip appears to just feed x/y/z spatial orientation to
the laptop. Then, the video frames from the 2d ultrasound are tagged with it?

Then some software to stitch it all together? Clever.

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borgchick
Clever indeed. I do wonder how hard it is to get the 2d images out of the
ultrasound though. I don't suppose it's just like a mjpeg stream like a
webcam.

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tyingq
At 1:31 in the video he appears to just plug into a DVI connector on the
ultrasound machine, which I assume goes into some kind of video capture card
on the laptop.

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pwinnski
3-D printing, software, and hardware together: this is really great!

