Brain images just got 64 million times sharper
medicalxpress.com
medicalxpress.com
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.
> The diffusion tensor images (DTI) @ 15 μm 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.
The highest resolution MR images I have (yet) obtained were ~20 µm^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.
Think of it like how you might be able to reverse engineer and recreate a microchip from high enough resolution imagery of an existing microchip.
One thing that the MRI studies don't address are the types of synaptic connections. Neurons aren't all just excitatory of inhibitory. There's a massive amount of modulation happen with numerous types of neurotransmitters and other signaling molecules.
We've had the complete C. elegans connectome for 30+ years, and know very little about how it actually generates behaviour... because synapses are only a small part of the picture.
[1] https://www.canadiannaturephotographer.com/rberdan_scanning_...
...but why?
The image was probably far more impactful pre-Photoshop; today a pocket-carried device can do that automatically, live, at 1080p/60fps.
Here is the link: https://www.youtube.com/watch?v=pqmLBXTL-Vs
How can 14 million pixels be 64 million times more pixels?
Were mouse brain images just one giant pixel previously?
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/15/5/639/442213?logi...
To be clear I used the term "pixels" in describing the characteristics of the final images produced, which are a series of stacked 2D images comprised of pixels.
But, I don't think it matters what we label the units we're counting, as long as we count them accurately.
The paper you've referenced states:
> field-of-view = 12 × 12 × 24 mm and matrix size = 200 × 200 × 400 giving an image with (60μm)[cubed] isotropic voxels
The "64 million times better" article states a resolution of 5μm voxels (for one aspect of the imaging). The paper the article references, by contrast, states 15μm when specifically comparing to MRI, and claims 1,000x improvement.
Diambiguating what is meant by "resolution" is a common problem, as it can refer to either the length of the axes or the overall area when multiplying them.
Conservatively, I'm going with 12x better resolution with the new technique when comparing apples to apples, or, to hype it reasonably: 5 cubed vs 60 cubed = a difference of 1,728 times more voxels in the same given area.
Not going to share the name of it? :)
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.
Have you noticed any other changes due to your lobectomy? (Isn't the amygdala responsible for fear, among other things?)
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.
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.
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:
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…
However if they use contrast it might have lasting effects. I only had that once and swear it made me feel dopey for weeks.
Only a tiny percentage of protons will actually get excited by a typical MRI. Like one in a million.
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.
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)
Yes it is incredibly expensive, but it is in fact already done.
> 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" https://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?
>This method is used in cell biology[2] and for microscopy of intact, often chemically cleared, organs, embryos, and organisms
https://en.m.wikipedia.org/wiki/Light_sheet_fluorescence_mic...
It doesn't sound like it will be used for live animals or human cadavers anytime soon?
Lagrangian points, non-intersecting paths through accretion discs, and microscopic black holes all preserve data - modulated energy; information - for some time before reversible or unreversible transformation.
Perhaps Superfluid quantum gravity can afford insight into the interior topology of black holes and other quantum foam phenomena?
(Edit)
Coping: https://en.wikipedia.org/wiki/Coping
Defence mechanisms § Level 4: mature: https://en.wikipedia.org/wiki/Defence_mechanism#Level_4:_mat...