[HN Gopher] CT Scan of a Pumpkin
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CT Scan of a Pumpkin
Author : zdw
Score : 348 points
Date : 2021-10-31 14:48 UTC (8 hours ago)
(HTM) web link (randomfootage.homestead.com)
(TXT) w3m dump (randomfootage.homestead.com)
| sabujp wrote:
| and for mri https://www.clovisopenmri.com/blog/512
| Grakel wrote:
| No pumpkin
| ufo wrote:
| Number 13 might count, depending on the definition of
| pumpkin.
| cunthorpe wrote:
| No upvote
| landonxjames wrote:
| Is "They did a CT scan on a pumpkin" the next evolution of "They
| did surgery on a grape"[0]?
|
| [0] https://knowyourmeme.com/memes/they-did-surgery-on-a-grape
| resoluteteeth wrote:
| Maybe it's the next evolution of doing an fMRI on a dead
| salmon: https://blogs.scientificamerican.com/scicurious-
| brain/ignobe...
| Kydlaw wrote:
| The most powerful CT Scan has been unveil very recently, with a
| magnet able to pull almost 12 teslas (where regular ones usually
| go to 1,5 to 3 teslas)[1]. Source is in french, but you'll find a
| similar video of... a pumpkin :)
|
| They explain in the article that pumpkins are used because they
| share a similar shape and structure as well as water ratio as a
| human head. They got the magnet from previous research efforts
| from a research team dedicated to that domain (part of the french
| research around nuclear and alternative energies). Instead of
| trashing the 130t magnet, they proposed to adapt it for medical
| imagery. It will know help research on the Alzheimer disease.
|
| https://www.francetvinfo.fr/sante/decouverte-scientifique/sc...
|
| Edit: format
| nosianu wrote:
| That's MRT - magnetic resonance imaging. CT scans - computed
| tomography - use x-rays.
|
| https://en.wikipedia.org/wiki/CT_scan
|
| https://en.wikipedia.org/wiki/Magnetic_resonance_imaging
|
| The applications for both are slightly different.
|
| https://www.medicalnewstoday.com/articles/154877#possible_ri...
|
| There is a nice course on edX (the content is free),
| "Introduction to Biomedical Imaging", which teaches the basics
| of the most common imaging technologies (also adds ultra-sounds
| and radiology-based scans):
|
| https://www.edx.org/course/introduction-to-biomedical-imagin...
| thangngoc89 wrote:
| Those were high resolution slices of CT scan and nice
| visualization as well. One can only hope human CT scans could
| achieve this level of preciseness without increasing the
| radiation dose.
| lostlogin wrote:
| > One can only hope human CT scans could achieve this level of
| preciseness without increasing the radiation dose.
|
| It looks like a pretty standard scan to me and the article says
| the protocol used is an extremity protocol.
|
| I work in radiology and various non-human things go though the
| scanner from time to time - fruit, pets, fossils, broken
| equipment that needs internal visualisation (sort of like the
| patients).
| superjan wrote:
| Sorry to be such a bore but when scanning humans the images
| should only be good enough to make a good diagnosis. If they
| are better than needed, the wise thing to do is lower the
| radiation exposure.
| happyhardcore wrote:
| Roughly how much higher is the dose required for this level of
| detail than that which is considered safe for humans?
| mertd wrote:
| No level of radiation exposure is safe. How much of CT
| radiation is considered acceptable depends on the
| application.
| lostlogin wrote:
| Dose response being linear no threshold is the operating
| assumption. Radiation hormesis may be a thing but it's
| difficult to be certain at low doses.
|
| https://en.m.wikipedia.org/wiki/Radiation_hormesis
| lostlogin wrote:
| As far as I can tell, it's not higher dose.
|
| > It was scanned on a GE Revolution CT machine. The scan was
| performed using technique optimized for human extremities,
| and employed very thin slice thickness of 600 microns.
| thaumasiotes wrote:
| > Next, it's obvious how much air there is in a pumpkin. All the
| black on these source images represent air, quite a bit of its
| overall volume.
|
| This made me really curious. The pumpkin is airtight and develops
| entirely within that airtight seal. It's full of gas pockets. How
| similar are the undisturbed contents of those gas pockets to
| atmospheric air?
| heavyset_go wrote:
| I wouldn't be surprised if gas exchange occurred through
| membranes, so that the gas inside is the same composition as
| the gas outside.
| emmelaich wrote:
| I'm pretty sure these pumpkins have been made to have more air
| for Halloween. Much easier to carve out.
|
| Everyday edible pumpkins have much more flesh.
| GuB-42 wrote:
| A pumpkin is not airtight. Like most living things, plants
| breathe in O2 and breathe out CO2 (in addition to
| photosynthesis which does the opposite). So the air inside a
| pumpkin is most likely atmospheric air with less O2 and more
| CO2, maybe other gasses that participate in the pumpkin
| metabolism.
| adrianmonk wrote:
| As a partially texture-based eater, looking at these images makes
| me feel triggered.
|
| But it also makes me feel grateful for food processors, blenders,
| etc. that can puree pumpkin into delicious pie filling.
| joelbondurant wrote:
| This pre-science must be censored until ordained by the Science
| Ministry.
| jliptzin wrote:
| I am considering whether to have a CT scan done of my heart. I am
| 35 yo and healthy, but have bad history of heart disease in my
| family. No current issues for me though. My doctor recommended I
| do the scan just to see if I have any plaque buildup, but is this
| not a lot of unnecessary radiation at a fairly young age? I hear
| it is like getting 1,000 x-rays done. Can anyone qualified chime
| in?
| PragmaticPulp wrote:
| The FDA has a great page on the topic with citations to medical
| journals: https://www.fda.gov/radiation-emitting-
| products/medical-x-ra...
|
| The short answer:
|
| > If you combine the natural risk of a fatal cancer and the
| estimated risk from a 10 mSv CT scan, the total risk may
| increase from 400 chances in 2000 to 401 chances in 2000.
|
| Your specific CT scan of the heart might be less than half of
| the 10mSv dose used in this example so the radiation risk is
| even lower.
| lostlogin wrote:
| Have a read up on what the dose is and what this equates to.
| It's low, and importantly, the alternative tests are pretty
| invasive.
|
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4789203/
| superjan wrote:
| For plaque buildup they normally do a quick low resolution scan
| (to calculate an "agatson score"). I did not know by heart, but
| according to webmd.com it's equivalent to 1 year background
| radiation. Pretty and high resolution images like the pumpkin
| above are possible but require more radiation. They should use
| the simplest scan that answers the doctor's question.
|
| A good question to ask is 'why': if no treatment decision
| depends on the outcome of the scan, the downsides can easily
| outweigh the benefits. A healthy lifestyle is advisable no
| matter what the scan says.
|
| I am no doctor. I work on software for cardiologists.
| jliptzin wrote:
| Thank you
| pjerem wrote:
| Better get some X-Rays than staying with unknown and untreated
| desease. This could help you :
| https://www.nuffieldhealth.com/article/radiation-exposure-fr...
|
| CT scans are way more radiative than your classical X-rays but
| they are also way less radiative that anything that could be
| really dangerous.
|
| You are way more prone to major heart issues if it's in your
| family's genes and untreated than to have any issue with a ct-
| scan.
| jliptzin wrote:
| Thanks, that does help
| 323 wrote:
| If you are in US, one thing to consider is the massive over-
| prescription of medical tests in this country, due to legal
| reasons - avoid being sued for missing a problem.
|
| You might want to consult with a UK doctor for example to see
| if they also recommend a CT scan in your situation.
|
| https://www.newyorker.com/magazine/2015/05/11/overkill-atul-...
| bonyt wrote:
| If you download the video and extract the frames (like, with
| ffmpeg), and load it into 3d Slicer (slicer.org), you can
| actually get a 3D reconstruction out of it! Out of a youtube
| video of the slices!
|
| https://i.imgur.com/wmPQvfn.jpg
| [deleted]
| anewlanguage wrote:
| I work with large-scale neuroscience imaging, and this is
| exactly how we compress 3D image stacks (i.e. 3d volumes)
| captured with confocal microscopes. Since adjacent frames are
| usually quite similar, there's a ton of redundancy that H.265
| can exploit, and the compression ratios are amazing. For multi-
| channel volumetric imaging, we use ffmpeg to encode each
| channel as a movie and then combine all the channels into a
| single HDF5 file.
| robocat wrote:
| Do you get 3D compression artifacts?
|
| I love the idea that you rotate a spacial dimension into a
| time dimension, and after decompression you get artifacts
| from the time dimension visualised in a space dimension
| again.
| anewlanguage wrote:
| We don't get visible artifacts because we dialed-in the CRF
| value to our data. But that sounds like a neat experiment
| to try.
| andbberger wrote:
| FIJI plugin?
| anewlanguage wrote:
| Yes: https://github.com/fiji/H5J_Loader_Plugin
| trombonechamp wrote:
| Oh wow, this is a great idea. How do you deal with the lossy
| compression? There must be a lossless codec which uses the
| redundancy better than deflate?
| anewlanguage wrote:
| This format is meant for visualization in 3d, and even
| though it's lossy, it's "visually lossless" for humans. We
| to start with the archived lossless stacks (compressed with
| bz2) for any reprocessing.
|
| What you're suggesting with a lossless movie codec would be
| a great addition, we just haven't had the need for it yet.
| DaftDank wrote:
| I wonder if this would work for my hospital CT scans I've had
| in the last ~5 years. They all come on a CD, with a software
| program loaded onto it with the scans to view it in. It would
| be cool to be able to 3d visualize it all
| Pigalowda wrote:
| Don't go through that much trouble! There's an easier
| solution.
|
| You can download free radiology viewers RadiAnt (windows
| compatible) or Osirix (Mac compatible). Your imaging is in
| DICOM format probably and you can use Radiant to export all
| of your slices into .jpg if you want. You can also do 3D
| reconstructions of soft tissue, bone, lung, etc.
| wtallis wrote:
| The program in question (3D Slicer) is _also_ one of those
| easier solutions. It can load DICOM files directly.
| lostlogin wrote:
| Horos (Mac) is another - I think it's the freeware version
| of Osirix.
|
| You can find InteleViewer if you hunt about as well (Mac
| and PC).
| dylan604 wrote:
| >Don't go through that much trouble!
|
| You realize this is HN where readers pride themselves on
| the trouble that can be accomplished in a weekend.
|
| >There's an easier solution.
|
| But what else is one to do at the weekend?
| spookthesunset wrote:
| Try to turn it into an stl file, slice it and print it
| :-)
| dylan604 wrote:
| Do this with a couple of "perfect" pumpkin shapes. Create
| a way to 3D print these as a mold to make your own
| "pumpkins" to be carved without all of the mess and able
| to last longer through the season. No more petroleum
| jelly, no more soaking them in the tub.
| idiotsecant wrote:
| >No more petroleum jelly, no more soaking them in the
| tub.
|
| What. I feel like I am missing out on a whole field of
| pumpkin science here that I was unaware of.
| dylan604 wrote:
| It's a plant. Think of it as a cut flower. After cutting
| open a pumpkin, they are obviously no longer sealed. They
| start to dry out. You can rub petroleum jelly all over
| the carved sides to help slow down the drying out. You
| can also soak them in the tub, and they will pull in some
| of the water to help them come back into shape.
|
| There's all sort of things you can do to prolong things
| once they've been cut/carved/etc. My mom was a florist
| and designer. I've been in/around productions requiring
| things to be preserved so items can be kept around as
| long as possible. You just kind of pick up a thing or two
| Turing_Machine wrote:
| There are also various chemical solutions that you can
| put on the pumpkin to make it last longer. However those
| are not recommended if wildlife is around. Moose, in
| particular, love pumpkins. I suspect deer are the same.
| dylan604 wrote:
| Sure the deer, but I don't want that stuff around me.
| Better living through chemistry is something I'm trying
| to avoid now that I can make my own choices about what
| goes in, on, or around me.
| jmkb wrote:
| personally I'm looking forward to "this gourd does not
| exist"
| hprotagonist wrote:
| there are many DICOM viewers available, ranging from the
| fairly horrible plugins for imageJ to very sophisticated
| things with maya or COMSOL or whatnot.
|
| OSIRX is often very good, though not free.
| azalemeth wrote:
| Horos is the FOSS version of Osirix and based on the same
| original codebase, which lives on Github - c.f.
| https://horosproject.org/download-horos/
| xvilka wrote:
| Sadly, it's MacOS-only. Would be nice to have something
| Qt or GTK-based.
| wazoox wrote:
| There are many free DICOM viewer in the
| Ubuntu/Debian/Pop_OS repositories. I don't remember which
| one I used, but at least some of them allow to visit your
| organs in 3D :)
| figomore wrote:
| I recommend InVesalius. It's in Flathub
| (https://flathub.org/apps/details/br.gov.cti.invesalius)
| BadInformatics wrote:
| You're in luck, because (assuming the scans are in a
| compatible format), this is exactly what 3D Slicer was
| designed for.
| manucorporat wrote:
| We have been working on an open source tech that works in the
| browser and render 3D CTs and MRIs without installing any
| software, check it out:
|
| https://openview.health
| nick__m wrote:
| When my wife when through invasive breast cancer some years
| ago1, I got started with RadiAnt because it's easy to
| construct a nice looking3d reconstruction, but I quickly hit
| a ceiling what I was able to accomplish.
|
| With slicer I was able to produced compelling pictures to
| highlight the objects of interest by using custom color
| scales and transparency. For fun I also followed some
| tutorial on bone segregation for 3d printing, something that
| is clearly beyond the reach of RadiAnt.
|
| Still, I would recommend to learn the basics in RadiAnt by
| trying to see what is in the written radiologist report2. You
| will have to learn quite a bit of arcane terminology but I
| found that process quite rewarding and strangely empowering.
|
| 1- 3 years after her last treatment she is still cancer free,
| I hope it stays that way...
|
| 2- Ask for a copy of the report when you get the DICOM DVD.
| If the scan was taken at a hospital they will probably
| redirect you to the medical archives and it assuredly won't
| be ready when you get the DVD but they can mail it to you.
| tamaharbor wrote:
| Happy Halloween!
| h3mb3 wrote:
| It certainly triggers my trypophobia!
| nealabq wrote:
| The pumpkin flowers have 5 petals, and the female flowers have 5
| stigma, but the seeds inside grow in 6 columns. Which I find
| puzzling.
|
| Google brings up
| https://threesixty360.wordpress.com/2009/10/31/the-mystery-o...
| which points out a 3-fold rotational symmetry in the pumpkin. And
| if you look, the 6 seed-columns are really 3 pairs of columns.
|
| Five and three seem less puzzling I supposed, because Fibonacci.
| Still, I was expecting 5.
| gus_massa wrote:
| I'm confused too, but look at this photo in the article
| http://randomfootage.homestead.com/pumpkinTangerine1.jpg
|
| It looks like there is an empty slot at 11-12 in the clock, and
| also an empty slot at 7 in the clock. Each one looks partially
| split in two, so I can imagine that they are the missing 2
| parts of the structure of the flower.
| Grimm1 wrote:
| Well that's one of the more interesting things I think I'll see
| today! Neat.
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