Spin echo sequences
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At the time the article was created J. Ray Ballinger had no recorded disclosures.
View J. Ray Ballinger's current disclosuresAt the time the article was last revised Lachlan McKay had no financial relationships to ineligible companies to disclose.
View Lachlan McKay's current disclosures- Spin echo sequences
- Spin echo pulse sequences
Spin-echo pulse sequences are one of the earliest developed and still widely used (in the form of fast spin echo) of all MRI pulse sequences. The pulse sequence timing can be adjusted to give T1-weighted, proton density, and T2-weighted images. Dual echo and multiecho sequences can be used to obtain both proton density and T2-weighted images simultaneously.
The two variables of interest in spin echo sequences are the repetition time (TR) and the echo time (TE). All spin echo sequences include a slice selective 90-degree pulse followed by one or more 180 degree refocusing pulses as shown in the diagrams.
The MR signal intensity (S) produced using a spin echo sequence is proportional to the proton density (ρH), TR, T1, TE and T2, described by the equation S ∝ ρH [1-eTR/T1]e-TE/T2 4.
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References
- 1. Bydder GM, Steiner RE. NMR imaging of the brain. Neuroradiology. 1982;23 (5): 231-40. Pubmed citation
- 2. Friedburg H, Bockenheimer S. [Clinical NMR tomography with sequential T2 images (Carr-Purcell spin-echo sequences)]. Radiologe. 1983;23 (8): 353-6. Pubmed citation
- 3. Stark DD, Bradley WG, Bradley WG. Magnetic resonance imaging. C.V. Mosby. (1999) ISBN:0815185189. Read it at Google Books - Find it at Amazon
- 4. Jerrold Bushberg. The Essential Physics of Medical Imaging,. (2020) ISBN: 9781975103224 - Google Books
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