Magnetic Resonance Imaging Explained
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- čas přidán 13. 10. 2011
- Dr D. Bulte from Oxford University's FMRIB (Functional Magnetic Resonance Imaging of the Brain) centre explains the theory underlying today's modern MRI scanners and outlines the work of the FMRIB centre.
If you are interested in the field of Biomedical Sciences, including Magnetic Resonance Imaging, please click on the link below to visit Oxford University's Biomedical Sciences undergraduate course.
www.medsci.ox.ac.uk/study/bms
This video was produced by Oxford Medical Illustration -- a non-profit making NHS department. For more information please click on the link below:
www.oxfordmi.nhs.uk - Věda a technologie
I absolutely love it when people who are knowledgeable about a subject explain the subject.
Best video about MRI there is...believe me, I searched all over
agreed, this one is the best one
I love how it's just technical enough so that you understand the fundamentals of what's going on, but he also does a great job of explaining how things work in a simple and easy to digest manner. Definitely have a better grasp as to what goes on now.
Thx
Man I would love to have such clarity in formulating my own thoughts. Impressive, informative, amazing
He explained so simply I now understand it. Thank you so very much Dr Daniel Bulte.
I visited the Siemens Healthcare factory in Erlangen, Germany as part of our Bachelor's Studies. The amount of cutting-edge engineering and technology that they have in order to manufacture these MRI machines is astonishing. Simply one of the "craziest" technology companies out there.
I hope nobody will repeat this demo near the MRI machine.Great video.
Hi Dr. Bulte ~ thank you for the clear and concise video explaining how MRI works, this really helped me study for radiology final exam in medical school! All the best from Seattle.
Congratulations Dr. D Bulte. Your explanation of MRI is the best I've ever read to date. This sharing of important information is most appreciated. Thank you!
Superb explanation, thanks. And I love the fact Dr B chooses 'doing calculus' as an example of what he might get a person to do during an fMRI session, not just 'maths' or 'sums'!
Been searching all over the place on how a scanner works. I finally landed here. Now I got it. Great explanation.
I've explained the functioning of an MRI in a basic form since they were first about in 1980, but this really blows that explanation out of the water and expands it way beyond - brilliant!
I really appreciate how to the point this is. Some people just drag things out and repeat themselves over and over which gets super annoying. Thank you!
Really a clear explanation about the MRI system. The only vedio on youtube which can clear the concept. Thank you sir for your great vedio
By far the best video I've seen about MRI, trust me i'm twelve and this is the video that helped me understand this concept
Simplest way one can explain T1 and T2 relaxation. Shukriya (Thanks) Dr Bulte
One of the best descriptions I've heard. Thanks you.
Aussie? I loved to know how it works, i asked thr operator and she was like ahhh i dont really know. hahaha
skilled. Thanks for this mate!
It's been 10 years since this video was posted..Still, it's my favorite
Smart man, thanks for making this, gave me some peace of mind.
Wonderful video. Thank you Dr. Bulte.
Great explanation, gonna have to see it a couple more times though.
Thank you. Now I understand a bit more about MRI.
Wow, really clear explanation, thank you.
Nice Video! quite informative for my A level Physics and chemistry as well
Awesome explanation...
Wonderful explanation! I feel like I finally understand MRI now!
That was real good explanation! Loved it
Very helpful. Thank you Dr. Bulte.
Thank you so much.... very useful... short but full of information!
GREAT explanation!
That is quite fascinating how two interacting (but opposing axis fields) can create a proton spin and thermal spike at that scale.
Brilliant explanation, could do with a little more on hydrogen non zero spin etc, but still the best video I can find
Signal in MR images is high or low (bright or dark), depending on the pulse sequence used, and the type of tissue in the image region of interest. The following is a general guide to how tissue appears on T1- or T2- weighted images.
Dark on T1-weighted image:
increased water, as in edema, tumor, infarction, inflammation, infection, hemorrhage (hyperacute or chronic)
low proton density, calcification
flow void
.
Bright on T1-weighted image:
fat
subacute hemorrhage
melanin
protein-rich fluid
slowly flowing blood
paramagnetic substances: gadolinium, manganese, copper
calcification (rarely)
laminar necrosis of cerebral infarction
.
Bright on T2-weighted image:
increased water, as in edema, tumor, infarction, inflammation, infection, subdural collection
methemoglobin (extracellular) in subacute hemorrhage..
..
Dark on T2-weighted image:
low proton density, calcification, fibrous tissue
paramagnetic substances: deoxyhemoglobin, methemoglobin (intracellular), iron, ferritin, hemosiderin, melanin
protein-rich fluid
flow void
Perfectly explained! Thank you very much
Very good explanation of a very complicated subject, although I wish you would have mentioned more about how gadolinium affects the contrast.
Extremely good video, thank you.
really clear explanation! thanks
Thank you so much! Brilliant explanation!
its 8 years since this was published but thankyou i really needed this for my physics asg lmaoo
Came to understand what kind of scan I just had in a MRI mashine. Now I'm totally clueless.
Physicist here and this explanation is amazing
You my friend...are a smart cookie. Thanks
Best explanation ever. Thank you
so articulate bro. wish u were my lecturer
Thanks for the video. Super cool!
This guy is good. Thanks for this video, helped a lot .
Best explanation on mri
great explanation!!! thank you million!
Excellent video!
amazing explanation!
Thanks! that was very helpful.
Amazing explanation
Thanks! That was quite helpful
Hello, I am studying EM-5 Comprehensive Electronics subjects on ac/dc motors. My question is what type of power supply does an MRI machine use? Single-phase or Three-phase? Just curious?
Very Good. I am Looking for some explanation for T1 and T2 imaging. and how does it happen?
Bravo, majstore!
I'm here because had 7 within a year due to a Brainstem Cavernoma found on Nov 2017 after having a stroke since it's in my pons doctors do not want to remove it they all say it's too risky I'm 36 yrs old never had any health problems just bad headaches thanks to an MRI doctors were able to diagnose me. For now all I can do it's wait and see since brain surgery it's not an option for me. Over all good video🤗 I kinda of got it
Hope everything went well...
Why was the N removed from the acronym MRI?
Thank you for this video!
very well explained!
Great content!
Great explanation, I agree.
SO helpful thank you sm
Very informative thank you.
Very informative, thank you.
Very useful explanation
Excellent thank you
Very informative video
nicely explained
Why my Dr. ordered me a CT-Scan. I want an MRI. i dont want to be expose to ionizing radiation please
Good job 👍
You're a life saver
That was great. Thanks a lot.
nice explained
I salute you Sir !!
Good explanation!
amazing stuff, i wonder what they were experimenting to discover this
Nuclear Magnetic Resonance - apparently that word was scary, so they chose the term MRI instead.
Its origin lies in a technique chemists use to help determine the structure of organic molecules called Nuclear Magnetic Resonance Spectroscopy. It uses a superconducting magnet (back in the early days of the technique, just strong ordinary magnets) and radio frequency light. The physics of NMR and MRI is exactly the same, the spin flip of a proton when immersed in a magnetic field. The two techniques just look at different aspects of it. NMR is more concerned about the absorption of radio frequency by nuclei in the magnetic field whereas MRI I believe is more concerned with the amount of time the nuclei spend in their excited states.
@@malayali_m NMR is still the term we used in the chemistry field. Same basic concept though.
@@8543960 , why such strong magnetic field (about 3 Tesla) is necessary?
excellent! thank you
thanks so much I finally understand.
Fascinating
Most expedient explanation on MRI..👌...all others will only ever say..3 magnets, an electromagnet, supplying current,...and boom you got the image...like wtf 😒
very helpful thank you.
Great!! Thank you
Very Helpful! Thank you ^_^
Amazing
Thanks for the explanation. I'd like to point out that particles are not spinning. Spin is a fundamental quantum property of the proton and has nothing to do with it spinning.
QSM?
Thank you...
Do you have a phd? You are incredible.
Thanks!
So articulate
So when you have a magnetic field on and your water particles are processing towards the initial B-field...you then turn on an orthogonal B-field to get the water particles to process towards that one (at a orbital of energy). But dont you have to turn off the orthogonal B-field once the water particles start processing with the orthogonal B-field so that they quickly jump back down a state because they will start processing towards the initial B-field. So once the the orthogonal B-field is turned off and the water particle is processed back to the initial B-field , doesnt the water particle emit a photon (which is light) and then they have a sensor waiting to catch all those photons to get a good image of bones,tissues,etc? emits a photon because of the jumping down from a higher orbital to a lower orbital? or am i thinking of it completely wrong?
You are basically correct. Individual protons absorb and emit photons, but the net magnetic moment (the sum of many, many protons) rotates down in a spiral motion while the B1 field is on, then spirals back up to the B0 direction once the B1 is removed.
Why is so difficult to get an MRI from your Dr? anyways.
I think this would have been better if he’s explaining the concept while lying down on the MRI and on side screen, we can simultaneously see his brain scan (real time)....
I'm not sure if the spin actually process in the transverse plane when RF pulse is applied, as explained from 2:30min. As far as I know, hydrogen can only have two energy states, high or low, and it is the NMV (Net Magnetic Vector) that lies in the transverse plane which gets detected by the reciever coil, NOT the magnetic moment nor the spin themselves.
This is exactly correct! The video is the physics tradition of "simplified to the point of being wrong", and we will reteach it all differently next year.
Are you sure? I think the video is saying correct
its v v v good
mind blown, im here cos i had an MRI scan of my wrist today.. damn
Why does the proton not immediately realign itself into the plane of the large (3T) magnetic field after the 2nd magnetic field is turned off?
The individual proton probably won't flip back at all. Think of it as adding energy to the system when they are flipped. Just like heating water, the system takes time to "cool down" until it reaches equilibrium again.
It will align itself eventually. But it will precess before doing so.
The explanation this physicist did was basic. Its much more complex than his explanation...Some tissues types realign faster than others. Taking a sample at a certain echo time (in milliseconds) will show tissues at certain states of relaxation.. There are also different types of relaxation.. There is longitudinal as well as spin lattice. Longitiudinal relaxation shows tissues in T1 and spin lattice show tissues in t2 relaxation...Each type of tissue has certain shades of white or grey for each type of relaxation. For example, Fat looks bright on a T1 weighted image, On a T2 weighted image Fat is somewhat bright but not as bright at T1... Spinal fluid is dark gray on a T1 and bright on T2 Sometimes its better to look at a mri image from google. search for t1 and t2 sagittal image of the lumbar spine and look at the bones, the disks, the spinal canal, the fat etc..... nerves, muscle, tendons, cartlidge , inflamation, generally look a dark grey on both t1 weighted and t2 weighted scans...bone metatasis looks dark on t1 scans,,, Google an image of a lumbar spine with bone mets and look at how it appears dark in the boneoon a t1 weighted scan. A compression fracture can also appear dark on a t1 weighted spine image. One cool thing about mri is you can saturate out certain tissues like fat to see fluid in t2 images...Fat saturation is where you can bombard the frequency that fat resonates at so that it has no signal . The reason you do this is because fat and fluid are bright on a t2 weighted image.. If you pulled a muscle in the leg and couldnt tell if there was fluid or fat in the tissues as they both look bright, you add fat sat to it so fat now becomes dark and fluid or inflamation now appears bright,,,,Google an mri image of muscle tear in the calf. You will see a t1 weighted fat sat scan shows bright fluid, the t1 weighted images shows that fluid dark. If you didnt use fat saturation on that scan the fluid in the leg would also look like fat...This is still a very simplistic look at mri...Its a lot more complicated than what I just wrote, but google is a good resource to as well as seeing pathology on a mri image....
Bravo
Thanks ;)