[HN Gopher] Brain images just got 64 million times sharper
       ___________________________________________________________________
        
       Brain images just got 64 million times sharper
        
       Author : amichail
       Score  : 179 points
       Date   : 2023-04-18 15:59 UTC (7 hours ago)
        
 (HTM) web link (medicalxpress.com)
 (TXT) w3m dump (medicalxpress.com)
        
       | lumenwrites wrote:
       | Can a technology like this at some point be used for brain
       | uploads? Or like a cheaper and better version of cryonics - to
       | "backup" the brain until it can be resurrected in some way?
        
       | CatWChainsaw wrote:
       | (Obligatory "in mice") but very exciting nonetheless. And not
       | just brains. I'm rather excited to see literal guts at a whole
       | new level of detail.
        
       | akozak wrote:
       | Lot of folks seems to be missing the fact that they slice the
       | brain up afterwards and merge those scans with the MRI data.
        
       | nick__m wrote:
       | 9.4 T is quite a strong magnetic field, as it is half the
       | strength of the magnetic field used for plasma confinement in
       | Tokamak Energy's Demo4 facility. Scaling this technology for
       | human-sized animals will likely be incredibly expensive, but the
       | 5 micron accuracy is surely worth the investment.
        
         | echo_time wrote:
         | 7T is already regularly used for human research, and approval
         | for human usage has been granted for 10.5T and I believe for
         | 11.7T (though I'm not sure how many images they've gotten out
         | of that yet).
         | 
         | Yes it is incredibly expensive, but it is in fact already done.
        
           | nick__m wrote:
           | I am impressed by what's possible, thank you !
        
           | westurner wrote:
           | https://thedebrief.org/impossible-photonic-breakthrough-
           | scie... :
           | 
           | > _For decades, that [Abbe diffraction] limit has operated as
           | a sort of roadblock to engineering materials, drugs, or other
           | objects at scales smaller than the wavelength of light
           | manipulating them. But now, the researchers from Southampton,
           | together with scientists from the universities of Dortmund
           | and Regensburg in Germany, have successfully demonstrated
           | that a beam of light can not only be confined to a spot that
           | is 50 times smaller than its own wavelength but also "in a
           | first of its kind" the spot can be moved by minuscule amounts
           | at the point where the light is confined._
           | 
           | > _According to that research, the key to confining light
           | below the previous impermeable Abbe diffraction limit was
           | accomplished by "storing a part of the electromagnetic energy
           | in the kinetic energy of electric charges." This clever
           | adaptation, the researchers wrote, "opened the door to a
           | number of groundbreaking real-world applications, which has
           | contributed to the great success of the field of
           | nanophotonics."_
           | 
           | > _"Looking to the future, in principle, it could lead to the
           | manipulation of micro and nanometre-sized objects, including
           | biological particles," De Liberato says, "or perhaps the
           | sizeable enhancement of the sensitivity resolution of
           | microscopic sensors."_
           | 
           | "Electrons turn piece of wire into laser-like light source"
           | (2022) https://news.ycombinator.com/item?id=33493885
           | 
           | Could such inexpensive coherent laser light sources reduce
           | medical and neuroimaging costs?
           | 
           | "A simple technique to overcome self-focusing, filamentation,
           | supercontinuum generation, aberrations, depth dependence and
           | waveguide interface roughness using fs laser processing" http
           | s://scholar.google.com/scholar?start=10&hl=en&as_sdt=5,4... :
           | 
           | > _Several detrimental effects limit the use of ultrafast
           | lasers in multi-photon processing and the direct manufacture
           | of integrated photonics devices, not least, dispersion,
           | aberrations, depth dependence, undesirable ablation at a
           | surface, limited depth of writing, nonlinear optical effects
           | such as supercontinuum generation and filamentation due to
           | Kerr self-focusing. We show that all these effects can be
           | significantly reduced if not eliminated using two coherent,
           | ultrafast laser-beams through a single lens - which we call
           | the Dual-Beam technique. Simulations and experimental
           | measurements at the focus are used to understand how the
           | Dual-Beam technique can mitigate these problems. The high
           | peak laser intensity is only formed at the aberration-free
           | tightly localised focal spot, simultaneously, suppressing
           | unwanted nonlinear side effects for any intensity or
           | processing depth. Therefore, we believe this simple and
           | innovative technique makes the fs laser capable of much more
           | at even higher intensities than previously possible, allowing
           | applications in multi-photon processing, bio-medical imaging,
           | laser surgery of cells, tissue and in ophthalmology, along
           | with laser writing of waveguides._
           | 
           | TL Transfer Learning might be useful for training a model to
           | predict e.g. [portable] low-field MRI with NIRS Infrared
           | and/or Ultrasound? FWIU, "Mind2Mind" is one way to ~train a
           | GAN from another already-trained GAN?
           | 
           | From https://twitter.com/westurner/status/1609498590367420416
           | :
           | 
           | > _Idea: Do sensor fusion with all available sensors
           | timecoded with landmarks, and then predict the expensive MRI
           | /CT from low cost sensors_
           | 
           | > _Are there implied molecular structures that can be
           | inferred from low-cost {NIRS, Light field, [...]} sensor
           | data?_
           | 
           | > _Task: Learn a function f() such that
           | f(lowcost_sensor_data) - > expensive_sensor_data_
           | 
           | FWIU OpenWater has moved to NIRS+Ultrasound for ~ live in
           | surgery MRI-level imaging and now treatment?
           | 
           | FWIU certain Infrared light wavelengths cause neuronal
           | growth; and Blue and Green inhibit neuronal growth.
           | 
           | What are the comparative advantage and disadvantages of these
           | competing medical imaging and neuroimaging capabilities?
        
           | legerdemain wrote:
           | What's the bore diameter for a 7T or a 10T magnet? All of the
           | ones I've seen wouldn't be wide enough for an adult human.
        
             | echo_time wrote:
             | They are human size research (and now clinical, albeit
             | limited so far) magnets, so big enough, think about 60cm.
             | It's an elbow rubbing environment, but sufficient for even
             | somewhat large adults. The animals magnets are super tiny,
             | of course.
        
               | legerdemain wrote:
               | I see a 7T model from Siemens with a standard 60cm bore.
               | Interesting!
        
       | mysterydip wrote:
       | I didn't know who Chuck Close was to appreciate the article's
       | metaphor, so for those wondering: "Close was an American painter,
       | visual artist, and photographer who made massive-scale
       | photorealist and abstract portraits of himself and others. Close
       | also created photo portraits using a very large format camera."
        
       | FriedPickles wrote:
       | Clicked on this expecting to read about an AI enhancement
       | technique. Was very refreshing to read about actual hardware
       | improvements.
        
         | Loquebantur wrote:
         | It's actually neither nor.
         | 
         | They just used the MRI to _map_ a high-resolution image
         | obtained via light sheet microscopy. I doubt you can do that
         | with living animals. Without slicing the brain that is.
         | 
         | The title here is highly misleading.
        
           | tgbugs wrote:
           | The number in the title is misleading but what you write here
           | is also misleading.
           | 
           | > The diffusion tensor images (DTI) @ 15 mm spatial
           | resolution are 1,000 times the resolution of most preclinical
           | rodent DTI/MRI. Superresolution track density images are
           | 27,000 times that of typical preclinical DTI/MRI.
           | 
           | The resolution of the raw MRI images is significantly higher,
           | without that increased resolution it would be impossible to
           | align the light sheet images. The light sheet images are not
           | use to "improve" MRI resolution.
        
           | kevviiinn wrote:
           | Light sheet microscopy is actually pretty neat. You can use
           | it on a whole brain without slicing it but not on a living
           | animal. The tissue needs to go through a special fixing
           | procedure first
        
           | SquirrelOnFire wrote:
           | Yeah, they kind of blow past light sheet microscopy, but I'm
           | optimistic that this can still be quite useful. There are
           | brain banks with already donated brains that we could use to
           | learn about diseases, and I imagine many organ donors would
           | be happy to have their brains sliced up for science.
        
         | dontwearitout wrote:
         | 5 micron voxels is extremely impressive. I'm excited to see
         | where this goes!
        
           | Udo wrote:
           | One more leap like this and we'll be able to resolve
           | individual dendrites and obtain a complete connectome.
           | Combined with microscopic slices (with suitable
           | immunohistological staining), we'd be getting close to
           | obtaining the data necessary for brain uploading - at least
           | in mice.
        
         | scythe wrote:
         | A key problem with high-res MRI in a living organism is the
         | scan time. Even fast acquisition techniques like EPI require
         | around 50 milliseconds per slice. But if you want good
         | resolution and contrast you're doing a spin echo which takes
         | quite a bit longer. At some point you run into motion blur
         | caused by the mere involuntary contraction of blood vessels,
         | and that's before you consider the difficulty with patient
         | compliance to the directive: _" hold still"_.
        
           | cperciva wrote:
           | If you want to scan the entire organism, sure. But higher
           | resolution MRI can also mean "scan a smaller part, with good
           | detail, in the same amount of time". I could imagine this
           | being useful for e.g. getting a high resolution image of a
           | tumour after conventional imaging was used to _locate_ it.
        
           | azalemeth wrote:
           | Indeed. To say nothing of gating acquisitions to breathing,
           | head motion, eye cicadas, glymphatic flow, etc.
           | 
           | The highest resolution MR images I have (yet) obtained were
           | ~20 um^3 voxels on ex vivo (human) tissue samples fixed in
           | agar with Gd3+ as a dopant, scanned at 12 T on a preclinical
           | scanner. The coupled vibration of the gradient set causing
           | blurring in the image domain at the extremities of the FOV
           | was the limiting factor. I recall I did a partial Fourier
           | acquisition - as ultimately we were limited by both T2* and
           | vibration - and ended up trying to do POCS on a 4096^3
           | dataset and just needing tons and tons of ram to do it over
           | something useful, like a weekend. Happy memories.
        
       | Animats wrote:
       | That's useful. 5 microns is very good. Probably more than is
       | needed for medical purposes. Some intermediate level between
       | current technology and this scale is a useful product.
        
         | drcode wrote:
         | Mice brains are a lot easier to image than human brains afaik,
         | solely because they can fit into such a tiny MRI tube, with far
         | simpler magnets. So if any mouse MRI tech is scaled to a human
         | device, it will almost certainly have far less resolution.
        
       | ravenstine wrote:
       | And they couldn't provide a better quality JPEG...
        
       | JackFr wrote:
       | How do you measure sharpness?
       | 
       | It's pretty impressive to say that the linear resolution
       | increased 400x, but I guess at 400x it's barely even clickbait.
       | It's far more impressive to cube it and claim 64000000x
       | improvement.
        
         | dosshell wrote:
         | Well, do you think a 4 Megapixel camera sensor has 2x
         | resolution compared to a 2 MP?
         | 
         | If no, I agree with you, but if it indeed does... Why should we
         | not compare resolution in the higest dimension here too? We
         | already have a term for linear resolution, voxel size.
         | 
         | (But yes. I agree with your clickbait argument here. Could have
         | been better to use voxel size in the heading)
        
       | SubiculumCode wrote:
       | I wonder if this resolution is possible only when the fov is
       | about the size of a mouse brain. Also, I bet the bore is tiny.
       | However, I didnt think 9.4T was enough.
        
         | [deleted]
        
       | RektBoy wrote:
       | Video with a title "Brain images just got 64 million times
       | sharper", in 240p ...killed me, hhehehe.
        
       | svag wrote:
       | So, if the normal MRI machines are the Hubble of medical imaging,
       | this new MRI machine is the James Webb of medical imaging?
        
       | w-m wrote:
       | 64e6^(1/3) = 400, in case you were wondering. So I would take it
       | that clinical MRI voxels measure 2 mm (400 * 5 um) usually? The
       | article does a really bad job at explaining the number from their
       | headline.
        
         | jonnycomputer wrote:
         | In the research setting, if a structural MRI is being acquired
         | for anatomical research, they'll go below than by more than
         | half. We acquire 2mm voxel structural MRIs since we only use it
         | to help us find a warp from subject space to template space in
         | fMRI analysis.
        
         | echo_time wrote:
         | Clinical scanners often use 2mm isotropic voxels, or even 3.
         | Clinical usage is almost a bad reference point!. Research MRI
         | at ultra high field (7T) goes to 0.8mm isotropic and below (0.5
         | or 0.6 is possible).
        
       | jonnycomputer wrote:
       | Such resolution will be largely wasted if the object in the
       | scanner does not remain still. Humans do not remains still.
        
       | maxmcd wrote:
       | Better link with better video:
       | https://today.duke.edu/2023/04/brain-images-just-got-64-mill...
        
         | diogopublio wrote:
         | love the psychedelic image and music, tech product
         | announcements kind lost their souls lately
        
       | danbruc wrote:
       | I case somebody else wonders, here [1] are some electron
       | microscope pictures of neurons [and other stuff] to better
       | understand what 5 um voxels means. Seems about one order of
       | magnitude away from being able to image all the connections.
       | 
       | [1]
       | https://www.canadiannaturephotographer.com/rberdan_scanning_...
        
         | CamperBob2 wrote:
         | That photo about halfway down the page, wow. Absolute maximum
         | creepiness.
        
           | LeifCarrotson wrote:
           | > The eyes of my wife were added in the darkroom before the
           | days of Photoshop and the image is titled "Donna".
           | 
           | ...but why?
           | 
           | The image was probably far more impactful pre-Photoshop;
           | today a pocket-carried device can do that automatically,
           | live, at 1080p/60fps.
        
       | davycro wrote:
       | I've always wanted to have an MRI. I want to know how it feels to
       | have all of my protons reoriented by a giant magnet. Would I be
       | the same person after?
        
         | jjtheblunt wrote:
         | The only thing you feel is heated a bit in my experience
         | (sports injuries, torso and sinuses).
         | 
         | However if they use contrast it might have lasting effects. I
         | only had that once and swear it made me feel dopey for weeks.
        
           | scythe wrote:
           | If you had nanoparticle contrast (ferumoxytol) it very well
           | could have stuck around for weeks. Gadolinium chelate
           | contrast is supposed to wash out in a few days, though.
        
         | yalue wrote:
         | Having to hold perfectly still (possibly in an uncomfortable
         | pose) in a giant machine that's making loud, uncanny noises for
         | 20+ minutes is indeed a very bizarre, meditative experience. It
         | is interesting, but, in my opinion, you're probably going to be
         | happier not having the health concerns that lead to getting an
         | MRI in the first place!
        
           | cj wrote:
           | I had a MRI in college as part of a psychology experiment.
           | 
           | If you can get into one of those studies, it's a free way to
           | get a picture of your brain!
           | 
           | I think I may have skewed their results, though. MRI is a
           | very meditative experience and I'm pretty sure I fell asleep
           | for brief moments when I was (supposed to be) memorizing and
           | recalling pictures and words they were showing me on a
           | monitor as part of the university experiment.
        
             | nuancebydefault wrote:
             | Indeed it tends to be meditative, especially because you
             | have nothing else to do then holding still and relax.
        
         | sigmoid10 wrote:
         | >to have all of my protons reoriented by a giant magnet
         | 
         | Only a tiny percentage of protons will actually get excited by
         | a typical MRI. Like one in a million.
        
           | echo_time wrote:
           | This is incorrect - all of the protons align along the static
           | (the strong 1.5, 3 , 9.4 etc Tesla) field, some point one
           | way, and some the other - but they have all shifted so that
           | they line up. The excite portion is a separate step, distinct
           | from the static (B0) field. edit: distinct in some ways - the
           | strength of the static field determines the RF used to flip
           | the protons out of alignment.
        
         | tonymillion wrote:
         | You can't feel it, and you have to stay still for a long time
         | sometimes in uncomfortable positions.
         | 
         | All the while trying not to laugh at the funny noises the
         | machine makes which will blur the image and make the procedure
         | even longer.
         | 
         | It really does sound like the machine is farting sometimes...
        
         | oh_sigh wrote:
         | I've had a few. There is definitely a weird feeling I get
         | inside of them at specific certain points in the process, but I
         | don't know if it is from the magnetic field, or if it is from
         | some really high pitch vibrations/sounds that come off the
         | machine.
        
         | gnarcoregrizz wrote:
         | I've felt a bit of heat from the radio waves, especially during
         | the fMRI sequence. Personally, I get a bit claustrophobic
         | during brain MRIs because of the restricting face coils, and
         | you have to go pretty deep into the tube. No idea why people
         | get weirded out by seeing pictures of their brain. I've never
         | felt that. I think its cool.
        
         | kelseyfrog wrote:
         | I've had a couple. Proton alignment is an imperceptible state.
         | You're experiencing more significant neurological changes
         | reading this message than having your protons reoriented.
        
           | robopsychology wrote:
           | My wife works on MRI sequencing and has pretty long (> 1
           | hour) MRI scans quite often (2/3 times a week) as they all
           | test each others research on themselves. She mentioned there
           | are some scans where you actually do feel them and it's quite
           | uncomfortable.
        
         | nuancebydefault wrote:
         | In the hospital where I went a few times, they show a relaxing
         | video while the MRI is taken. You look at a projection via a
         | tilted mirror close to your eyes. Once it was featuring pandas,
         | it is really nice to experience the panda effect inside the
         | machine. I've never been anxious about the scan.
        
         | jlokier wrote:
         | Your protons are also oriented by the Earth's magnetic field,
         | and the magnets in your phone speakers. Larmor precession (the
         | effect) occurs in low fields just as in high fields. The energy
         | state differences from Earth's field are generally too small to
         | be useful for MRI with enough quality in a reasonable time, but
         | low-field MRI is a research area.
         | 
         | I actually felt a strong sensation when I had a high resolution
         | brain MRI for research, and I rather enjoyed it. It switched on
         | and off a few times during the scan, and it felt a bit like
         | having a back massage, or significant mechanical vibrations in
         | my back, or that feeling like gentle electric currents during
         | some therapies, except for switching on and off abruptly.
         | 
         | I asked about this after the scan because I had been told you
         | don't feel anything. Surely it wasn't just my imagination, from
         | the noises? Was it from machine vibrations? I didn't have any
         | metal in my body except amalgam fillings, and they said those
         | wouldn't affect it. And, if I could feel something, perhaps it
         | wasn't as harmless as they made out.
         | 
         | They explained after, some people feel a stimulation of their
         | peripheral nervous system when the RF is on, from the tens of
         | kW of microwave energy beamed through the body. For a few
         | people this sensation is too much, even painful, and they have
         | to stop which is one reason for the patient having the
         | mechanical alert button. But most people don't feel anything at
         | all from the MRI, just psychological feelings associated with
         | the strange noises and confinemnt.
         | 
         | They said it's a peripheral nerve stimulation sensation, a kind
         | of phantom feeling, rather than a physical effect on the body
         | being sensed by the nerves. Don't ask me why I felt it in my
         | back given it was a head and neck scan.
         | 
         | I enjoyed how it felt when I didn't know what it was, as it
         | felt like it might loosen up my back a bit. I was a bit
         | disappointed to not feel anything the next time I had a head
         | MRI, for a medical reason (thankfully nothing found). The
         | research scan had twice the field strength of the medical scan,
         | and presumably different RF settings. Perhaps that made the
         | difference.
        
           | scythe wrote:
           | >low-field MRI is a research area.
           | 
           | Not just a research area! Recently on the DXMP mailing list
           | someone was asking about QA procedures for their 0.064 tesla
           | scanner. You can buy permanent magnets that strong without
           | much trouble. I was very surprised since I wasn't aware they
           | were in production -- even searching Web results for "low-
           | field MRI" in due diligence for this comment, I still only
           | find papers and projections. Nonetheless, the Hyperfine Swoop
           | exists, and you can buy it today:
           | 
           | https://hyperfine.io/
        
             | eevmanu wrote:
             | any idea how much could "Hyperfine Swoop System" cost?
             | since pricing is not public
        
         | wincy wrote:
         | The MRI didn't feel like anything. It wasn't until the
         | neurologist showed me images of my brain with my eyeballs right
         | there in the front that I felt like I was going to have a panic
         | attack. I have no idea how regular people just laugh off stuff
         | like that. Awful existential crisis level dread seeing my
         | mental meat.
        
           | anodyne33 wrote:
           | Former epileptic, I've had dozens of MRs and CTs. It's rote
           | for me to see and I never had a visceral reaction and in fact
           | I find it pretty fascinating. The one that I do have that's a
           | standout and quite shocking is my first post-lobeectomy MRI.
           | There's a very noticeable void where my right temporal lobe
           | (+amygdala, cerebellum and hippocampus) were resected. Great
           | conversation starter.
        
             | codethief wrote:
             | Good to hear you're no longer suffering from epilepsy!
             | 
             | Have you noticed any other changes due to your lobectomy?
             | (Isn't the amygdala responsible for fear, among other
             | things?)
        
           | 13of40 wrote:
           | For anyone wanting to relive that experience, you should know
           | that (in the US at least) you can go to the imaging
           | department at the hospital and get all of that data on a CD,
           | and there's some good free software to render it. I've got a
           | 3D print of my head somewhere that I made from a CT scan.
        
             | Workaccount2 wrote:
             | I did this and then realized I have no way of using a CD.
        
               | sundarurfriend wrote:
               | You can buy portable CD reader/writers for pretty cheap
               | (that connect to a USB port).
        
             | Nuzzerino wrote:
             | > some good free software to render it
             | 
             | Not going to share the name of it? :)
        
               | echo_time wrote:
               | If the images are in DICOM format, which is common, then
               | dcm2niix should be able to convert them
               | https://github.com/rordenlab/dcm2niix
               | 
               | I think it can handle a few other formats as well. Once
               | they are .nii(.gz) files, then mricrogl
               | (https://www.nitrc.org/projects/mricrogl) should be able
               | to render it - of course, for a brain scan - this would
               | be your whole head. Brain extraction is performed by more
               | specialized software, but that would get you started.
        
             | ttoinou wrote:
             | Noo way? My CD only contains a bunch of jpeg from the
             | slices. What file format did you get ?
        
           | rcme wrote:
           | I got an MRI of my knee after my injury. It didn't seem
           | significant in any way. The ultrasound of my pregnant wife
           | was way crazier to me.
        
             | macintux wrote:
             | I haven't had either, but my knee is far more
             | disposable/replaceable/independent of my self-identity.
        
           | wewtyflakes wrote:
           | I had a similar feeling when the doctor showed the MRI images
           | going progressively deeper into my brain. It was truly
           | bizarre and made me squirm in discomfort. I hadn't expected
           | to feel that way.
        
         | RobotToaster wrote:
         | I found it oddly relaxing and fell asleep.
        
       | stansler wrote:
       | Would be nice to have a better resolution for a sample video on
       | YouTube (https://www.youtube.com/watch?v=FtOQddvp_U4), 64 million
       | times sharper, but video quality is only 240p :)
        
         | maxmcd wrote:
         | Better video: https://www.youtube.com/watch?v=Z4WvWIJCFJc
        
         | Retric wrote:
         | I don't know if they can. 240 cubed is ~14 million while a
         | mouse Brian only has 8-14 million neurons.
         | https://en.wikipedia.org/wiki/Mouse_brain
        
           | detrites wrote:
           | Well something isn't adding up.
           | 
           | How can 14 million pixels be 64 million times more pixels?
           | 
           | Were mouse brain images just one giant pixel previously?
        
             | Retric wrote:
             | > How can 14 million pixels be 64 million times more
             | pixels?
             | 
             | It's Voxels not pixels. Voxels are 3D objects so to be
             | clear this particular advancement isn't 64 million (roughly
             | 400 in each linear dimension^3) times better than the best
             | that came before. Think 400x400 = 160,000 more pixels and
             | 400 times as many slices.
             | 
             | Also the comparison is to a "typical clinical MRI for
             | humans" which not only have 10 billion neurons but also
             | tend to have relatively few slices. There's little point in
             | having people spend hours in a machine if a faster scan
             | with fewer slices is good enough.
             | 
             | Anyway, while the point of comparison is suspect this is
             | still a major improvement over earlier methods just look at
             | the by comparison low resolution images in this paper from
             | 2005. https://academic.oup.com/cercor/article/15/5/639/4422
             | 13?logi...
        
           | DefineOutside wrote:
           | If you render a 240p video as 4k on youtube - the bitrate
           | will be much higher and it will be less compressed than if it
           | is uploaded as a 240p video.
        
       | skybrian wrote:
       | This seems to be a process that can be used on _dead_ mouse
       | brains.
       | 
       | It doesn't sound like it will be used for live animals or human
       | cadavers anytime soon?
        
       | NeuroCoder wrote:
       | This is interesting for basic research but this strategy is
       | unlikely to ever make it to human research. We need to find ways
       | of extracting more information at reasonable Tesla. 9T just isn't
       | gonna make its way to clinic
        
       ___________________________________________________________________
       (page generated 2023-04-18 23:01 UTC)