5 ms·

Taking digital X-ray shots for cheap

97 points by _Microft 5y ago

_Microft 5y ago
Don’t feel bad when you see what some people are able to build in hardware. It’s their job (now) - the author is working at NeuraLink these days, building wireless charging for brain implants. (This is meant to say: they are really good at it) More of their stuff with with x-rays on Twitter: https://mobile.twitter.com/search?q=from%3Alucysrausch%20x-ray&src=typed_query&f=top https://mobile.twitter.com/search?q=from%3Alucysrausch%20x-r...
- goldenkey 5y ago
  Why would it matter if it was their job or not? My friend has been doing circuitry since he was a kid. He can run circles around me doing embedded while I can run circles around him when it comes to software. Our jobs are irrelevant, it's our initial interests that caused us to specialize. United, we build awesome stuff together. There's no reason to feel bad when people with different interests have way better skills in their specialties. Instead of feeling bad, form alliances and make awesome stuff together.
  - ddingus 5y ago
    This! In my peer group, we do similar things. Just share projects. And skills rub off. I am good at hardware, meh at software. Everyone is improving. Fun, and good for careers in the future.
willis936 5y ago
I feel bad for sharing this because it's a master class in things to never do with HV and the creator made a follow-up video mocking commenters criticizing this, but it's similar and interesting. https://youtu.be/IiJAq53knwc https://youtu.be/IiJAq53knwc
- tgsovlerkhgsel 5y ago
  That's both hilarious and scary. For his own sake, I hope a lot of it is just a shtick and he is actually much more careful about safety than he admits.
- willcipriano 5y ago
  Watched that and found a video about the people who got mad: https://www.youtube.com/watch?v=WDhr5E50Nds https://www.youtube.com/watch?v=WDhr5E50Nds The shovel bit is worth the time.
ad404b8a372f2b9 5y ago
If the sensor is so small why are the X-ray machines at my hospital almost room sized? You know those huge mechanical arms hanging from the ceiling that look like they could crush you or irradiate you to death. Also can this project be used on flesh and will I accidentally cook myself doing it?
- blululu 5y ago
  The size of an x-ray grows with power for two reasons: higher voltages require much more insulation, and higher energies require much more shielding. In medical contexts shielding is the big issue. I forget the exact figures but the mass attenuation coefficient for large energy is something like Z/E^3, so a dental x-ray at 15 kev will has much less radiation leakage than a chest x-ray at 150 kev. (Note that the beam is not monochromatic and the 1000x change in attenuation passes through an exponential decay relation so it is not a simple relation, but you need a lot of lead to keep the x-ray tech safe).
- jcrawfordor 5y ago
  Besides offering much higher power levels, the bulk of most hospital X-ray equipment seems to just be positioning... i.e. the actual X-ray generator is fairly small (although things like a projected light illuminator to help the technician with aim make it bigger), but there's a lot of "accessory" equipment just to make it easy for the technician to position it in the right place and have it stay there. Ceiling tracks and a specially designed patient bed with a pretty x-ray transparent material that the sensor can be placed under, for example. Dental X-ray machines for example are very small, but I think it's because they operate at pretty low power and have pretty simple/consistent positioning requirements. Panoramic dental x-ray machines on the other hand are pretty big because of the specific positioning. On top of that I think a lot of hospitals just have pretty old X-ray machines... they're expensive and can operate for a long time with maintenance and tube replacements. I've seen clinics that upgraded their x-ray process to digital by using a standalone digital sensor like this, but are still using a 20+ year old analog machine as the x-ray source. I think that's why this particular sensor doesn't accept triggering information over the digital interface... that seems kind of weird at first glance, but I assume it was designed as a drop-in replacement for film, so it would be used with an older machine that didn't have any kind of digital trigger output. Instead it just detects when the exposure has started. Presumably the manual told the technician what parameters they needed to use on the emitter for it to get a full scan. The author here mentioned using a hand-held X-ray emitter for sports medicine which I'm curious about because I've never seen such a thing. I assume the power and exposure time must be pretty limited, even the dental X-ray machines have a regulatory requirement that the operator be behind a shield during use---although the implementation is usually pretty lax, just putting the exposure button in the hallway outside the x-ray nook so they have to step outside briefly.
geocrasher 5y ago
Since when is "for cheap" the right way to say things. Ugh.
- Stampo00 5y ago
  According to Google Books Ngram Viewer, the first recorded usage of the phrase "for cheap" was noted in 1672, although that could be part of a longer phrase like "for cheap food". Usage peaked in 1876. I'm willing to bet that at least some of that usage mirrors how the author is using it. In conclusion, "for cheap" has been the "right way to say things" since before either of us were born. https://books.google.com/ngrams/graph?content=for+cheap&year_start=1500&year_end=2019&corpus=26&smoothing=3&direct_url=t1%3B%2Cfor%20cheap%3B%2Cc0 https://books.google.com/ngrams/graph?content=for+cheap&year...
  - pbhjpbhj 5y ago
    >In conclusion, "for cheap" has been the "right way to say things" since [...] // The more people that get it wrong the righter (sic) it is! :eyeroll:
    - Stampo00 5y ago
      Why aren't you speaking Old English?
      - pbhjpbhj 5y ago
        I'm guessing you're accusing me of prescriptivism -- OE of a bad choice, spelling and grammar were basically anarchy (Latin might have been a better choice?). I'm not a proscriptivist, language use changes but I don't believe majority usage is automatically correct.
        Stampo00 5y ago
        If those using the language don't decide what's "correct" (whatever that means), who does? If the person listening can understand the meaning the speaker was trying to convey, that's as correct as it can be. You don't have to like it. But who are you to declare something objectively right or wrong?
marcodiego 5y ago
How safe is playing with this?
- MegaDeKay 5y ago
  The comments in the linked article have response to a question like this that states: "All safety precautions are complied with, also have a dosimeter for direct radiation warnings."
neilv 5y ago
I only got partway through the entertaining video, before I had an impulse to pause it and check the YouTube comments about safety. There's so much of what seemed like poorly-informed belligerence in the YouTube comments, it felt like I was reading foreshadowing of tragedies.
fortran77 5y ago
I'm able to solder Ball Grid Arrays at home, after a bit of practice, but I have no way to inspect them. I would love a cheap home Xray machine just for this purpose.
- techdragon 5y ago
  I’d love this too, I also know it would be illegal where I live. Unlicensed operation of an X-Ray emitter gets heavily frowned upon in Australia.
  - fortran77 5y ago
    How would they know? It's not too hard to generate X-rays. See https://www.youtube.com/watch?v=yLSu_UjrcUA https://www.youtube.com/watch?v=yLSu_UjrcUA
    - techdragon 5y ago
      I mean look, how do they know if you break the speed limit? They can't most of the time, and it's not like with radio emissions where they could easily triangulate a troublesome source. I dislike a LOT of the nanny-state bullshit over-regulation here in Western Australia... Hell I've even been personally affected by the decision to arbitrarily label some of my possessions as prohibited weapons in contrast to other states deciding they just needed to be registered, while other states again don't even care and treat them like the toys they are. So the overreach isn't just a game of hypotheticals for me... but I've never felt like the right answer is to blatantly ignore the fairly sensible if otherwise annoying laws.

97 points by _Microft 5y ago

Don’t feel bad when you see what some people are able to build in hardware. It’s their job (now) - the author is working at NeuraLink these days, building wireless charging for brain implants. (This is meant to say: they are really good at it) More of their stuff with with x-rays on Twitter: https://mobile.twitter.com/search?q=from%3Alucysrausch%20x-ray&src=typed_query&f=top https://mobile.twitter.com/search?q=from%3Alucysrausch%20x-r...

goldenkey 5y ago
Why would it matter if it was their job or not? My friend has been doing circuitry since he was a kid. He can run circles around me doing embedded while I can run circles around him when it comes to software. Our jobs are irrelevant, it's our initial interests that caused us to specialize. United, we build awesome stuff together. There's no reason to feel bad when people with different interests have way better skills in their specialties. Instead of feeling bad, form alliances and make awesome stuff together.
- ddingus 5y ago
  This! In my peer group, we do similar things. Just share projects. And skills rub off. I am good at hardware, meh at software. Everyone is improving. Fun, and good for careers in the future.

willis936 5y ago

I feel bad for sharing this because it's a master class in things to never do with HV and the creator made a follow-up video mocking commenters criticizing this, but it's similar and interesting. https://youtu.be/IiJAq53knwc https://youtu.be/IiJAq53knwc

tgsovlerkhgsel 5y ago
That's both hilarious and scary. For his own sake, I hope a lot of it is just a shtick and he is actually much more careful about safety than he admits.
willcipriano 5y ago
Watched that and found a video about the people who got mad: https://www.youtube.com/watch?v=WDhr5E50Nds https://www.youtube.com/watch?v=WDhr5E50Nds The shovel bit is worth the time.

ad404b8a372f2b9 5y ago

If the sensor is so small why are the X-ray machines at my hospital almost room sized? You know those huge mechanical arms hanging from the ceiling that look like they could crush you or irradiate you to death. Also can this project be used on flesh and will I accidentally cook myself doing it?

blululu 5y ago
The size of an x-ray grows with power for two reasons: higher voltages require much more insulation, and higher energies require much more shielding. In medical contexts shielding is the big issue. I forget the exact figures but the mass attenuation coefficient for large energy is something like Z/E^3, so a dental x-ray at 15 kev will has much less radiation leakage than a chest x-ray at 150 kev. (Note that the beam is not monochromatic and the 1000x change in attenuation passes through an exponential decay relation so it is not a simple relation, but you need a lot of lead to keep the x-ray tech safe).
jcrawfordor 5y ago
Besides offering much higher power levels, the bulk of most hospital X-ray equipment seems to just be positioning... i.e. the actual X-ray generator is fairly small (although things like a projected light illuminator to help the technician with aim make it bigger), but there's a lot of "accessory" equipment just to make it easy for the technician to position it in the right place and have it stay there. Ceiling tracks and a specially designed patient bed with a pretty x-ray transparent material that the sensor can be placed under, for example. Dental X-ray machines for example are very small, but I think it's because they operate at pretty low power and have pretty simple/consistent positioning requirements. Panoramic dental x-ray machines on the other hand are pretty big because of the specific positioning. On top of that I think a lot of hospitals just have pretty old X-ray machines... they're expensive and can operate for a long time with maintenance and tube replacements. I've seen clinics that upgraded their x-ray process to digital by using a standalone digital sensor like this, but are still using a 20+ year old analog machine as the x-ray source. I think that's why this particular sensor doesn't accept triggering information over the digital interface... that seems kind of weird at first glance, but I assume it was designed as a drop-in replacement for film, so it would be used with an older machine that didn't have any kind of digital trigger output. Instead it just detects when the exposure has started. Presumably the manual told the technician what parameters they needed to use on the emitter for it to get a full scan. The author here mentioned using a hand-held X-ray emitter for sports medicine which I'm curious about because I've never seen such a thing. I assume the power and exposure time must be pretty limited, even the dental X-ray machines have a regulatory requirement that the operator be behind a shield during use---although the implementation is usually pretty lax, just putting the exposure button in the hallway outside the x-ray nook so they have to step outside briefly.

geocrasher 5y ago

Since when is "for cheap" the right way to say things. Ugh.

Stampo00 5y ago
According to Google Books Ngram Viewer, the first recorded usage of the phrase "for cheap" was noted in 1672, although that could be part of a longer phrase like "for cheap food". Usage peaked in 1876. I'm willing to bet that at least some of that usage mirrors how the author is using it. In conclusion, "for cheap" has been the "right way to say things" since before either of us were born. https://books.google.com/ngrams/graph?content=for+cheap&year_start=1500&year_end=2019&corpus=26&smoothing=3&direct_url=t1%3B%2Cfor%20cheap%3B%2Cc0 https://books.google.com/ngrams/graph?content=for+cheap&year...
- pbhjpbhj 5y ago
  >In conclusion, "for cheap" has been the "right way to say things" since [...] // The more people that get it wrong the righter (sic) it is! :eyeroll:
  - Stampo00 5y ago
    Why aren't you speaking Old English?
    - pbhjpbhj 5y ago
      I'm guessing you're accusing me of prescriptivism -- OE of a bad choice, spelling and grammar were basically anarchy (Latin might have been a better choice?). I'm not a proscriptivist, language use changes but I don't believe majority usage is automatically correct.
      - Stampo00 5y ago
        If those using the language don't decide what's "correct" (whatever that means), who does? If the person listening can understand the meaning the speaker was trying to convey, that's as correct as it can be. You don't have to like it. But who are you to declare something objectively right or wrong?

marcodiego 5y ago

How safe is playing with this?

MegaDeKay 5y ago
The comments in the linked article have response to a question like this that states: "All safety precautions are complied with, also have a dosimeter for direct radiation warnings."

neilv 5y ago

I only got partway through the entertaining video, before I had an impulse to pause it and check the YouTube comments about safety. There's so much of what seemed like poorly-informed belligerence in the YouTube comments, it felt like I was reading foreshadowing of tragedies.

fortran77 5y ago

I'm able to solder Ball Grid Arrays at home, after a bit of practice, but I have no way to inspect them. I would love a cheap home Xray machine just for this purpose.

techdragon 5y ago
I’d love this too, I also know it would be illegal where I live. Unlicensed operation of an X-Ray emitter gets heavily frowned upon in Australia.
- fortran77 5y ago
  How would they know? It's not too hard to generate X-rays. See https://www.youtube.com/watch?v=yLSu_UjrcUA https://www.youtube.com/watch?v=yLSu_UjrcUA
  - techdragon 5y ago
    I mean look, how do they know if you break the speed limit? They can't most of the time, and it's not like with radio emissions where they could easily triangulate a troublesome source. I dislike a LOT of the nanny-state bullshit over-regulation here in Western Australia... Hell I've even been personally affected by the decision to arbitrarily label some of my possessions as prohibited weapons in contrast to other states deciding they just needed to be registered, while other states again don't even care and treat them like the toys they are. So the overreach isn't just a game of hypotheticals for me... but I've never felt like the right answer is to blatantly ignore the fairly sensible if otherwise annoying laws.