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Template:Table of MRI sequences

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This table is used in the following articles:


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This table does not include uncommon and experimental sequences.

Group Sequence Abbr. Physics Main clinical distinctions Example
Spin echo T1 weighted T1 Measuring spin–lattice relaxation by using a short repetition time (TR) and echo time (TE).

Standard foundation and comparison for other sequences

T2 weighted T2 Measuring spin–spin relaxation by using long TR and TE times
  • Higher signal for more water content[1]
  • Low signal for fat in standard Spine Echo (SE),[1] though not with Fast Spin Echo/Turbo Spin Echo (FSE/TSE). FSE/TSE is the standard of care in modern medicine because it is faster. With FSE/TSE, fat has high signal due to disruption of hyperfine J-coupling between adjacent fat protons.[3]
  • Low signal for paramagnetic substances[2]

Standard foundation and comparison for other sequences

Proton density weighted PD Long TR (to reduce T1) and short TE (to minimize T2).[4] Joint disease and injury.[5]
Gradient echo (GRE) Steady-state free precession SSFP Maintenance of a steady, residual transverse magnetisation over successive cycles.[7] Creation of cardiac MRI videos (pictured).[7]
Effective T2
or "T2-star"
T2* Spoiled gradient recalled echo (GRE) with a long echo time and small flip angle[8] Low signal from hemosiderin deposits (pictured) and hemorrhages.[8]
Susceptibility-weighted SWI Spoiled gradient recalled echo (GRE), fully flow compensated, long echo time, combines phase image with magnitude image[9] Detecting small amounts of hemorrhage (diffuse axonal injury pictured) or calcium.[9]
Inversion recovery Short tau inversion recovery STIR Fat suppression by setting an inversion time where the signal of fat is zero.[10] High signal in edema, such as in more severe stress fracture.[11] Shin splints pictured:
Fluid-attenuated inversion recovery FLAIR Fluid suppression by setting an inversion time that nulls fluids High signal in lacunar infarction, multiple sclerosis (MS) plaques, subarachnoid haemorrhage and meningitis (pictured).[12]
Double inversion recovery DIR Simultaneous suppression of cerebrospinal fluid and white matter by two inversion times.[13] High signal of multiple sclerosis plaques (pictured).[13]
Diffusion weighted (DWI) Conventional DWI Measure of Brownian motion of water molecules.[14] High signal within minutes of cerebral infarction (pictured).[15]
Apparent diffusion coefficient ADC Reduced T2 weighting by taking multiple conventional DWI images with different DWI weighting, and the change corresponds to diffusion.[16] Low signal minutes after cerebral infarction (pictured).[17]
Diffusion tensor DTI Mainly tractography (pictured) by an overall greater Brownian motion of water molecules in the directions of nerve fibers.[18]
Perfusion weighted (PWI) Dynamic susceptibility contrast DSC Measures changes over time in susceptibility-induced signal loss due to gadolinium contrast injection.[20]
  • Provides measurements of blood flow
  • In cerebral infarction, the infarcted core and the penumbra have decreased perfusion and delayed contrast arrival (pictured).[21]
Arterial spin labelling ASL Magnetic labeling of arterial blood below the imaging slab, which subsequently enters the region of interest.[22] It does not need gadolinium contrast.[23]
Dynamic contrast enhanced DCE Measures changes over time in the shortening of the spin–lattice relaxation (T1) induced by a gadolinium contrast bolus.[24] Faster Gd contrast uptake along with other features is suggestive of malignancy (pictured).[25]
Functional MRI (fMRI) Blood-oxygen-level dependent imaging BOLD Changes in oxygen saturation-dependent magnetism of hemoglobin reflects tissue activity.[26] Localizing brain activity from performing an assigned task (e.g. talking, moving fingers) before surgery, also used in research of cognition.[27]
Magnetic resonance angiography (MRA) and venography Time-of-flight TOF Blood entering the imaged area is not yet magnetically saturated, giving it a much higher signal when using short echo time and flow compensation. Detection of aneurysm, stenosis, or dissection[28]
Phase-contrast magnetic resonance imaging PC-MRA Two gradients with equal magnitude, but opposite direction, are used to encode a phase shift, which is proportional to the velocity of spins.[29] Detection of aneurysm, stenosis, or dissection (pictured).[28]
(VIPR)
  1. ^ a b c d "Magnetic Resonance Imaging". University of Wisconsin. Archived from the original on 2017-05-10. Retrieved 2016-03-14.
  2. ^ a b c d Johnson KA. "Basic proton MR imaging. Tissue Signal Characteristics". Harvard Medical School. Archived from the original on 2016-03-05. Retrieved 2016-03-14.
  3. ^ Henkelman, RM; Hardy, PA; Bishop, JE; Poon, CS; Plewes, DB (September 1992). "Why fat is bright in RARE and fast spin-echo imaging". Journal of magnetic resonance imaging : JMRI. 2 (5): 533–40. doi:10.1002/jmri.1880020511. PMID 1392246.
  4. ^ Graham D, Cloke P, Vosper M (2011-05-31). Principles and Applications of Radiological Physics E-Book (6 ed.). Elsevier Health Sciences. p. 292. ISBN 978-0-7020-4614-8.}
  5. ^ du Plessis V, Jones J. "MRI sequences (overview)". Radiopaedia. Retrieved 2017-01-13.
  6. ^ Lefevre N, Naouri JF, Herman S, Gerometta A, Klouche S, Bohu Y (2016). "A Current Review of the Meniscus Imaging: Proposition of a Useful Tool for Its Radiologic Analysis". Radiology Research and Practice. 2016: 8329296. doi:10.1155/2016/8329296. PMC 4766355. PMID 27057352.
  7. ^ a b Luijkx T, Weerakkody Y. "Steady-state free precession MRI". Radiopaedia. Retrieved 2017-10-13.
  8. ^ a b Chavhan GB, Babyn PS, Thomas B, Shroff MM, Haacke EM (2009). "Principles, techniques, and applications of T2*-based MR imaging and its special applications". Radiographics. 29 (5): 1433–49. doi:10.1148/rg.295095034. PMC 2799958. PMID 19755604.
  9. ^ a b Di Muzio B, Gaillard F. "Susceptibility weighted imaging". Retrieved 2017-10-15.
  10. ^ Sharma R, Taghi Niknejad M. "Short tau inversion recovery". Radiopaedia. Retrieved 2017-10-13.
  11. ^ Berger F, de Jonge M, Smithuis R, Maas M. "Stress fractures". Radiology Assistant. Radiology Society of the Netherlands. Retrieved 2017-10-13.
  12. ^ Hacking C, Taghi Niknejad M, et al. "Fluid attenuation inversion recoveryg". radiopaedia.org. Retrieved 2015-12-03.
  13. ^ a b Di Muzio B, Abd Rabou A. "Double inversion recovery sequence". Radiopaedia. Retrieved 2017-10-13.
  14. ^ Lee M, Bashir U. "Diffusion weighted imaging". Radiopaedia. Retrieved 2017-10-13.
  15. ^ Weerakkody Y, Gaillard F. "Ischaemic stroke". Radiopaedia. Retrieved 2017-10-15.
  16. ^ Hammer M. "MRI Physics: Diffusion-Weighted Imaging". XRayPhysics. Retrieved 2017-10-15.
  17. ^ An H, Ford AL, Vo K, Powers WJ, Lee JM, Lin W (May 2011). "Signal evolution and infarction risk for apparent diffusion coefficient lesions in acute ischemic stroke are both time- and perfusion-dependent". Stroke. 42 (5): 1276–81. doi:10.1161/STROKEAHA.110.610501. PMC 3384724. PMID 21454821.
  18. ^ a b Smith D, Bashir U. "Diffusion tensor imaging". Radiopaedia. Retrieved 2017-10-13.
  19. ^ Chua TC, Wen W, Slavin MJ, Sachdev PS (February 2008). "Diffusion tensor imaging in mild cognitive impairment and Alzheimer's disease: a review". Current Opinion in Neurology. 21 (1): 83–92. doi:10.1097/WCO.0b013e3282f4594b. PMID 18180656. S2CID 24731783.
  20. ^ Gaillard F. "Dynamic susceptibility contrast (DSC) MR perfusion". Radiopaedia. Retrieved 2017-10-14.
  21. ^ Chen F, Ni YC (March 2012). "Magnetic resonance diffusion-perfusion mismatch in acute ischemic stroke: An update". World Journal of Radiology. 4 (3): 63–74. doi:10.4329/wjr.v4.i3.63. PMC 3314930. PMID 22468186.
  22. ^ "Arterial spin labeling". University of Michigan. Retrieved 2017-10-27.
  23. ^ Gaillard F. "Arterial spin labelling (ASL) MR perfusion". Radiopaedia. Retrieved 2017-10-15.
  24. ^ Gaillard F. "Dynamic contrast enhanced (DCE) MR perfusion". Radiopaedia. Retrieved 2017-10-15.
  25. ^ Turnbull LW (January 2009). "Dynamic contrast-enhanced MRI in the diagnosis and management of breast cancer". NMR in Biomedicine. 22 (1): 28–39. doi:10.1002/nbm.1273. PMID 18654999. S2CID 5305422.
  26. ^ Chou Ih. "Milestone 19: (1990) Functional MRI". Nature. Retrieved 9 August 2013.
  27. ^ Luijkx T, Gaillard F. "Functional MRI". Radiopaedia. Retrieved 2017-10-16.
  28. ^ a b "Magnetic Resonance Angiography (MRA)". Johns Hopkins Hospital. Retrieved 2017-10-15.
  29. ^ Keshavamurthy J, Ballinger R et al. "Phase contrast imaging". Radiopaedia. Retrieved 2017-10-15.