The Turbo & Fast Spin Echo Sequence - MRI Pulse Sequences EXPLAINED | MRI Physics Course Lecture 10

On this episode of MRI Physics Explained, we pick up right where we left off on the previous Spin Echo lecture and try to figure out if the Standard Spin Echo Sequence can be improved. Can we find a way to increase imaging speed while preserving image quality, improving access to MRI imaging in the process while keeping the hospital coffers full and our hospital CEOs in their private jets? Find out now on the latest episode of MRI physics explained, the Turbo & Fast Spin Echo Sequence!
CHAPTERS
00:00-01:54 Intro/Recap
01:54-03:42 Generating a 2nd Echo
03:42-05:04 The Turbo/Fast Spin-Echo Sequence
05:04-07:03 Imaging Time & Echo “Train” Length
07:03-09:50 Image Contrast
09:50-10:36 Outro
Like these lectures and want more? Consider supporting the quest for truth in MRI Physics by becoming a CZcams member!
Want me to bring these lectures live to your practice or institution packed full of live demos and a lot of arm waving? Send an email to: [e-mail]
Questions or suggestions for future topics? Send an email or follow Dr. TE on:
Instagram at: / lightsonradiology
Twitter: @DrTEMD
Song: JOXION & EXYT - Testify [Arcade Release] Music provided by NoCopyrightSounds Free Download/Stream: ncs.io/testify Watch: ncs.lnk.to/testifyAT/youtube
Song: Malik Bash - Ghosts [NCS Release] Music provided by NoCopyrightSounds Free Download/Stream: ncs.io/Ghosts Watch: • Malik Bash - Ghosts [N...
#mri #radiology #physics #course #spin #echo #radiologytutorial #radiologycourse #pulse

[@AsapYums]

please keep posting videos! very helpful as a Mri student!

[@MRIPhysicsEXPLAINED]

Got a lot more content in the pipeline, be sure to subscribe so you can be notified when new lectures drop and best of luck with your studies!

[@lucaya]

Great. Thank you!

[@MRIPhysicsEXPLAINED]

Glad it was helpful!

[@robinxavier1494]

thanks for this quality content🙂

[@MRIPhysicsEXPLAINED]

Thank you!

[@user-jl9po7ce4g]

Thank you.

[@MRIPhysicsEXPLAINED]

You're welcome, hope it helped!

[@TAHA-TOUABA-RADIOGRAPHER]

thank you so much pro

[@MRIPhysicsEXPLAINED]

Thanks for watching and commenting!

[@rik4351]

I'm working my way through these lectures and it's insane to me we still haven't arrived at k-space yet. My teacher started working with k-space at lecture 1 about 1D MRI...

[@MRIPhysicsEXPLAINED]

K-space is by far the most challenging concept! It's frustrating how courses introduce it out of nowhere as if anyone has an idea of what it is or how it plays into the MRI image building process. Unfortunately, to really understand it you have to dive deep into the math and really understand 3-4 subjects in parallel so the initial lectures present a general idea on how this all works while avoiding the math. I will cover this subject and all needed to understand it in a future Advanced MRI Physics lecture series so stay tuned but don't fret, if you asked an MRI technician to show you K-space, they wouldn't be able to. It is only relevant to those literally building and coding the MRI machines, but nonetheless a cool and interesting topic when explained well!

[@Grazieeee-f9q]

Hi LightsonRadiology!
Just want to let you know that we still use Spin echo commonly in MSK procedures.
Commonly T1 SE. Radiologists believes or the Specialists says that using TSe/FSe blurs the quality of the image. So I believe that they use this on T1 is
- It has low TR value than T2 hence the time could be around 3-5mins.
-Since it is used primarily for anatomy, Ligaments and tendons are a lot easier to see because it isn't blurred.
.
I never really understood why they say it blurs the image. Can you shed a light on to this?

[@MRIPhysicsEXPLAINED]

Ah the mysterious world of MSK, where the PD roams freely and apparently the conventional spin echo alongside it. Remember in the end, making images that allow radiologists to see the anatomy and pathology are of the upmost importance, and we are always trying to find that balance between saving imaging time with these advanced techniques while still seeing what we need to see. As you can tell in this lecture, the topic of contrast becomes more complicated with the TSE/FSE sequence. Here is an excerpt from an article discussing specifically T1 contrast in MSK imaging with these advanced techniques.
"The number of echoes obtained during one TR of FSE and TSE pulse sequences (i.e., the ETL) is one of the most potent means of reducing the scanning time because the number of echoes within an echo train is directly and inversely proportional to the acquisition time (see equation 1). However, certain considerations apply when choosing the ETL. Although the effective TE determines which echoes define the contrast of the MR image, peripheral echoes within the echo train also contribute to contrast, and longer echo trains thus inherently increase the T2-weighting of the MR image. Although this often is an acceptable or even desired effect of musculoskeletal MRI when using FSE and TSE pulse sequences with intended fluid sensitivity, achieving T1 contrast with FSE and TSE pulse sequences requires limiting ETLs to 3 or 4."
At such a short ETL, it may be most beneficial to just use the conventional Spin Echo and get slightly better images on the T1 sequences. Full article here: ajronline.org/doi/full/10.2214/AJR.20.22901.

[@Grazieeee-f9q]

That is so true. I once used a Philips scanner that uses a turbo factor around 7 and it actually looks like a PD even though they used 450 TR and 12TE. Thanks for the response!@@MRIPhysicsEXPLAINED

[@TAHA-TOUABA-RADIOGRAPHER]

second!

[@Grazieeee-f9q]

First!

[@MRIPhysicsEXPLAINED]

Got it!