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The most powerful MRI scanner in the world delivers its first images
- 1cvmask 5y agoFun MRI fact. It should be called NMRI or short for Nuclear Magnetic Resonance Imaging. But then no one would use it. https://en.wikipedia.org/wiki/Magnetic_resonance_imaging https://en.wikipedia.org/wiki/Magnetic_resonance_imaging
- a_t48 5y agoWhy? We use XRays already.
- throwawaylinux 5y agoAre any xray imaging services sold under a name like ionizing radiation beam photography?
- whatshisface 5y agoI don't think use of the word "radiation" is as necessary as you may be suggesting for the purpose of technical specificity. In fact it is a very broad word. Visible light is radiation.
- throwawaylinux 5y agoI never suggested it was necessary for the purpose of technical specificity, what on earth gave you that idea?
- whatshisface 5y agoThe theme of the comment thread is "isn't it bad that the public's fear of radiation prevents us from calling them NMRIs," but I am arguing that it's not such a tragedy after all.
- lostlogin 5y agoRadiology.
- throwawaylinux 5y agoYeah, I guess that's true.
- dghughes 5y agoThe unit at my local hospital where the MRI machines are located is named Nuclear Medicine.
- froh 5y agoWhere nuclear stands for nucleus, atom, not for radiation or radioactive decay... In German language is called "Kernspintomographie", "Kern"=nucleus or nuclear, and people happily use both the word and the device.
- samplatt 5y agoWikipedia says the previous world record[1] for an MRI magnet was 11.75 Teslas. This article says this one uses 11.7 Teslas. Anyone more knowledgeable care to comment on the difference? They say a record for this volume (large enough to pass a human) but surely the other one would be that large as well? [1] (2014) http://irfu.cea.fr/en/Phocea/Vie_des_labos/Ast/ast_technique.php?id_ast=2305 http://irfu.cea.fr/en/Phocea/Vie_des_labos/Ast/ast_technique...
- robbiep 5y agoit says in both the article you link and the actual article that it's the first one for clinical, rather than research use
- azalemeth 5y agoCEA is definitely not (yet) for clinical use, i.e. treating sick people routinely. It's for clinical research, i.e. scanning sick or healthy people, potentially (if and only if in the context of a registered clinical trial) changing their treatment as a corollary.
- jcims 5y agoThere’s also a bullet at the bottom of the article that says that the world record is for the volume at that field strength.
- kergonath 5y agoIt’s very simple: it’s because the story and your link talk about the same magnet. Yours was (initially) written when it was in the design phase, and it has now produced its first images.
- samplatt 5y agoThat's what I get for not properly investigating the sources. Thanks!
- VWWHFSfQ 5y agoare these the guys that did the scan of a pumpkin. is that what they made the powerful scanner for
- jlokier 5y agoNo, that was a CT scan. Different operating principle. CT scan uses X-rays beams from many angles, like taking X-ray photographs from different angles, and the images are combined mathematically into a 3D image. X-rays are a lot like regular visible light, they travel in straight beams and form clear images when focused, except unlike visible light, many substances are more transparent to X-rays. MRI uses radio signals in the microwave or below frequency range combined with a high strength magnet with a shaped magnetic field to make a field strength gradient. The radio waves resonate with some atomic nuclei at a frequency which depends on the magnetic field strength, so the combination of magnetic field gradient and radio frequency creates a thin layer in space where resonance occurs, affecting the radio waves in that layer while they pass through the rest of space much less affected. The layer is moved around, radio receivers pick up the affected signal, and the 3D image is reconstructed from that signal.
- kergonath 5y agoThe pumpkin here is just a test. They are still tuning it and at some point want to look at brains with a 100 μm resolution. They just cannot put living people in it before it’s been tested and certified.
- mattkrause 5y agoFruit and vegetables are pretty popular test objects: they sit nice and still, they have interesting structures (i.e., look cool), and they avoid ethics/safety issues involved in scanning humans or animals. "Phantoms", test devices with specific and well-known properties, are used for more careful testing but produce works pretty well for a quick sanity check.
- toomuchtodo 5y agoIs there a theoretical limit to how many Teslas an MRI machine can produce safely and would be useful for imaging?
- jcims 5y agoYou can make a frog float in a field of 16T https://www.science.org/content/article/floating-frogs https://www.science.org/content/article/floating-frogs
- TedDoesntTalk 5y ago> The frog, although bewildered, was apparently none the worse for wear, with "no physical sign of any malfunction," Might be safe anyway
- jcims 5y agoMost likely its relatively safe. Not sure about animals that have active magnetic field sensory capability. Given that it’s reacting to every water molecule in your body, it probably actually feels like you’re weightless.
- Aeolun 5y agoI think I read a short blog post about that a while before: https://gravityandlevity.wordpress.com/2015/01/12/how-strong-would-a-magnetic-field-have-to-be-to-kill-you/ https://gravityandlevity.wordpress.com/2015/01/12/how-strong... At least for how much would be safe.
- 6nf 5y agoI think we're not too far off from the limit. Even with 3T machines people report weird effects when moving their heads around during the scan.
- lostlogin 5y agoThat’s just the radiographer yelling at them. Moving in the scanner doesn’t cause you much sensation at all. However move quickly near the entrance to the bore and you get vertigo.
- azalemeth 5y agoWe've had preclinical 12T and way above machines for a while now (Bruker will sell you a ~21T, 1 GHz Larmour frequency machine, for instance). They are great for some forms of spectroscopy, but the issue for imaging is that t2* becomes very short, t1 becomes long, and it becomes impossible to have good b1 or b0 homogeneity. This means that the images are not necessarily filled with as much contrast as you'd like, tend to be a bit artefact-filled, and will keep physicists like me in pay for a long time. Still very cool though, and well done to the CEA team.
- xattt 5y agoIs there a magnet strength sweet spot for diagnostic imaging?
- lostlogin 5y agoI’m an MR tech. 1.5T magnets are a joy to use. Ideally a small bore and with big gradients (please) - Siemens Avanto Fit or similar.
- Sophistifunk 5y agoCould you repeat this in english? It's good for imaging big features but not small features, or high frequency density changes, or takes too long, or what?
- m3kw9 5y agoMore powerful isn’t as practical as it sounds
- whatshisface 5y agoB0 is the magnetic field that separates the nuclear spin energy levels. It's the one that's really big in this machine. B1 is the radiofrequency pulse that excites the nuclear spins. Poor B0 and B1 homogeneity means you are taking the MRI with a slightly different machine at every point. T1 is the time it takes for the energy that B1 adds to the nuclear spins to leak back out of the nuclei. It generally happens faster when the energy per nucleus, which is proportional to the degree to which B0 has split the energy levels, is low. If I had to guess, it's probably because there are more weak couplings by which a nucleus can get rid of a little energy than there are strong couplings that can support a big jump. One of the major things that limits the speed at which NMR can be done is the fact that you have to wait for this energy to leak out before you can put more in for another round of imaging. (Maybe there is a way around this but if so they never taught me about it.) T2 is the time it takes for the excited spins to fall out of phase with each other. It happens faster when there is a greater diversity of electronic influences on each nuclear environment - a bunch of identical atoms in a perfect lattice would never go out of phase. If you "zoom in" on T2 and study it with incredible precision you can pick apart each distinct environment around each population of similar nuclear neighborhoods. A population of identical neighborhoods, in practice, means a chemical. Chemists use that a lot but it's not done in imaging.
- jonbaer 5y agoJust for reference there are examples in the units page ... https://en.wikipedia.org/wiki/Tesla_(unit) https://en.wikipedia.org/wiki/Tesla_(unit)
- johnwheeler 5y agoWhy the crappy low res images in TFA
- kergonath 5y agoNo idea. The actual resolution of the pictures they took is 400 μm.
- 6nf 5y agoCan we see these pictures anywhere?
- wiz21c 5y agoSome in the "dossier de presse" at the bottom of the page https://www.cea.fr/presse/Documents/DP/2021/Dossier%20de%20Presse%20Iseult_Premi%c3%a8res%20images_07102021_VF-compress%c3%a9.pdf https://www.cea.fr/presse/Documents/DP/2021/Dossier%20de%20P...
- vimy 5y agoIs there a (theoretical) possibility of having portable MRI scanners someday? The size of a big suitcase or maybe even something like the tricorder in Star Trek. Like how we have portable ultrasound. https://www.ultrasoundportables.com/by-manufacturer/butterfly/butterfly-iq-ultrasound-scanner-for-iphone-and-android https://www.ultrasoundportables.com/by-manufacturer/butterfl... Although I realize an MRI scanner is a lot more complex.
- Fordec 5y agoWhile it's not the single barrier, but room temperature super conductors would go a ways to reduce the necessary bulk. But the magnetic fields would still be huge, you wouldn't want to just turn one on in your living room before some serious magnetic shielding technology was also invented.
- jonnycomputer 5y agoI attended a talk that was trying to develop something like that. Lots of challenges, but his goal was to make MRI cheap and portable. Sorry, I don't remember his name, but googling portable MRI or low-field MRI will give lots of results, e.g. this one: https://www.goodnewsnetwork.org/fda-approves-worlds-first-portable-mri-scanner/ https://www.goodnewsnetwork.org/fda-approves-worlds-first-po...
- axg11 5y agohttps://hyperfine.io/ https://hyperfine.io/ This is as close as we have right now.
- version_five 5y agoThe scanner needs a static field that's homogeneous over the region you're imaging. And magnetic fields can't be homogeneous outside the bore of a magnet, i.e in free space (Ernshaw's theorem maybe). So any portable scanner has to either have a small, locally homogeneous spot (see Blümich et al from the late 90s or what Schlumberger has done with borehole logging) or be some kind of bigger closed thing like the Hyperfine systems that a sibling post mentioned. It's a very interesting field from a technical perspective, but there are fundamental physical principles standing in the way of making a portable scanner like an ultrasound
- omginternets 5y agoCool! I worked at the NeuroSpin lab in ten years ago, and I recall the 11.5T giving people a lot of grief. There was significant doubt about whether it would ever work. IIRC one of the biggest issues was that it would pull in microscopic metal dust, which would then line the imaging tunnel and distort the image. I wonder how they resolved this.
- bozhark 5y agopositive pressure?
- omginternets 5y agoI doubt the push from the positive pressure would be enough to offset 11.5T worth of pull, but perhaps that was part of the solution. I really don’t know.
- kergonath 5y agoVery good question. I remember them mentioning this in an internal video, but I don’t think they detailed a solution. It’s a bit out of my field, to be honest.
- omginternets 5y agoSame. I was doing MEG stuff there anyway (Stan’s team). Out of curiosity, which team were you with?
- kergonath 5y agoI’m not at Neurospin, I’m a materials physicist on the other side of the fence, so to speak :). I just have a keen interest in what they’re doing there. My daughter also participated in a study on neuroplasticity and cerebral development in infants there and it’s been an interesting experience.
- omginternets 5y ago
- bozhark 5y ago132 ton magnet, wow
- hammock 5y agoWhat does a more powerful magnet get you? Finer resolution? Quicker scans?
- lostlogin 5y agoYes or yes. However it comes down to time or resolution with MR. You can’t have both.
- dghughes 5y agoI always thought an MRI worked a bit like a microwave oven that it would jiggle water or the hydrogen molecules in a person. The jiggling made the molecules emit energy, radio emissions. But it's much more precise than that. nibib.nih.gov has a nice explanation. >MRIs employ powerful magnets which produce a strong magnetic field that forces protons in the body to align with that field. When a radiofrequency current is then pulsed through the patient, the protons are stimulated, and spin out of equilibrium, straining against the pull of the magnetic field. When the radiofrequency field is turned off, the MRI sensors are able to detect the energy released as the protons realign with the magnetic field. The time it takes for the protons to realign with the magnetic field, as well as the amount of energy released, changes depending on the environment and the chemical nature of the molecules. Physicians are able to tell the difference between various types of tissues based on these magnetic What's strange is for clarity of images an old-fashioned x-ray/CAT scan is better it's not as fuzzy as 1T or 3T MRI. From what I can gather is the more powerful an MRI is the faster it can capture images and with more detail. The speed is why they are clearer you the patient has less time to squirm around. It's also mean less time for the patient to be in the machine and the machine is less constrictive (bigger hole).
- RL_Quine 5y agoPretty often for cerebral scans you don't have a whole lot of room to move due to being literally restrained by the focusing gear. Most people who have done MRIs regularly get pretty good at not blurring the images; the more still you remain the less chance of them having to do another round.
- johnisgood 5y agoI stayed still for my first, too. It was really noisy. I dislike the part where it suddenly changes the "rhythm" but I prepared myself for that now. Going to get an MRI soon again.
- RL_Quine 5y agoYou do get used to it, believe it or not. One thing that helped me understand what was going on was looking at the output files, each pulse of the magnet is a slice within the images, and each sound corresponds to different types of measurement. I tend to just count them to work out what type of imaging is currently going on, it's ultimately pointless but it's something to focus on given the lack of other stimulus. You'll know you're there when the MRI tech comments that it's obvious you've done a lot of them because every image was perfect.
- pontifier 5y agoInteresting that they mention the link to fusion magnets. I'm currently in the market for a used MRI scanner to supply the external field to my prototype fusion reactor. One reason I'm looking at MRI is the extreme uniformity or the field. I'm likely to get a much better field than I'd otherwise get if I tried to build one myself. I only need a fairly old, ~.35T permanent magnet model to do what I need, but the uniformity is vital.
- version_five 5y agoIs there any public information about what you are building? .35T is not that high and it may be easier and cheaper to build a permanent magnet array that meets your needs vs being to repurpose a scanner. I'd be curious to know what kind of field profile you want
- pontifier 5y agoI have more info, and a link to my patent at http://www.DDPROfusion.com http://www.DDPROfusion.com
- ramraj07 5y agoI’ll pass. Not gonna stick my head in anything more than 3T ever. Even at 7T you start getting disoriented which means the field has some effect on your head? Not sure why anyone would ignore that.
- roywiggins 5y agoThere's some reason to believe it's because the field interacts with the inner ear: https://www.hopkinsmedicine.org/news/media/releases/johns_hopkins_researchers_pinpoint_the_cause_of_mri_vertigo https://www.hopkinsmedicine.org/news/media/releases/johns_ho... https://pubmed.ncbi.nlm.nih.gov/30969883/ https://pubmed.ncbi.nlm.nih.gov/30969883/ Realistically, you will only be in a 7T or higher scanner if you a) sign up for a research study or b) really need it. There aren't that many of them!
- DLay 5y agoI had the pleasure of being a test subject for my local hospital’s new 7T last week. They strapped my head down to the table and I was only able to listen to the intermittent “DO-DO-DO-DO” of the machine, while a mirrored television played 15 minute aerial footage of Norway’s fjords on repeat for an hour. Reminded me a little of the brainwashing scene from A Clockwork Orange. The radiology report said, “No significant incidental findings identified,” so that’s good at least.
- opwieurposiu 5y agoWow, that's really nice of you to help your hospital get the bugs worked out on the new machine. Did you experience any heating? If so was it in your dental fillings?
- sgt 5y agoGo 100T and you're looking at healing powers: https://www.gateworld.net/wiki/Sarcophagus https://www.gateworld.net/wiki/Sarcophagus
- pcj-github 5y agoWhy does an article titled... "WORLD PREMIERE The most powerful MRI scanner in the world delivers its first images!" ... have only a single (crappy) image. Sigh.
- jonplackett 5y agoDelivers its images... to somewhere other than this article.
- findalex 5y agoThe radiologists are ants.