This table is used in the following articles:
- Magnetic resonance imaging#Sequences
- MRI sequences#Overview table
- Physics of magnetic resonance imaging#Overview of main sequences.
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 |
Standard foundation and comparison for other sequences |
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Proton density weighted | PD | Long TR (to reduce T1) and short TE (to minimize T2).[4] | Joint disease and injury.[5]
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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] |
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Perfusion weighted (PWI) | Dynamic susceptibility contrast | DSC | Measures changes over time in susceptibility-induced signal loss due to gadolinium contrast injection.[20] |
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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) |
- ^ a b c d "Magnetic Resonance Imaging". University of Wisconsin. Archived from the original on 2017-05-10. Retrieved 2016-03-14.
- ^ 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.
- ^ 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.
- ^ 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.}
- ^ du Plessis V, Jones J. "MRI sequences (overview)". Radiopaedia. Retrieved 2017-01-13.
- ^ 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.
- ^ a b Luijkx T, Weerakkody Y. "Steady-state free precession MRI". Radiopaedia. Retrieved 2017-10-13.
- ^ 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.
- ^ a b Di Muzio B, Gaillard F. "Susceptibility weighted imaging". Retrieved 2017-10-15.
- ^ Sharma R, Taghi Niknejad M. "Short tau inversion recovery". Radiopaedia. Retrieved 2017-10-13.
- ^ Berger F, de Jonge M, Smithuis R, Maas M. "Stress fractures". Radiology Assistant. Radiology Society of the Netherlands. Retrieved 2017-10-13.
- ^ Hacking C, Taghi Niknejad M, et al. "Fluid attenuation inversion recoveryg". radiopaedia.org. Retrieved 2015-12-03.
- ^ a b Di Muzio B, Abd Rabou A. "Double inversion recovery sequence". Radiopaedia. Retrieved 2017-10-13.
- ^ Lee M, Bashir U. "Diffusion weighted imaging". Radiopaedia. Retrieved 2017-10-13.
- ^ Weerakkody Y, Gaillard F. "Ischaemic stroke". Radiopaedia. Retrieved 2017-10-15.
- ^ Hammer M. "MRI Physics: Diffusion-Weighted Imaging". XRayPhysics. Retrieved 2017-10-15.
- ^ 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.
- ^ a b Smith D, Bashir U. "Diffusion tensor imaging". Radiopaedia. Retrieved 2017-10-13.
- ^ 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.
- ^ Gaillard F. "Dynamic susceptibility contrast (DSC) MR perfusion". Radiopaedia. Retrieved 2017-10-14.
- ^ 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.
- ^ "Arterial spin labeling". University of Michigan. Retrieved 2017-10-27.
- ^ Gaillard F. "Arterial spin labelling (ASL) MR perfusion". Radiopaedia. Retrieved 2017-10-15.
- ^ Gaillard F. "Dynamic contrast enhanced (DCE) MR perfusion". Radiopaedia. Retrieved 2017-10-15.
- ^ 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.
- ^ Chou Ih. "Milestone 19: (1990) Functional MRI". Nature. Retrieved 9 August 2013.
- ^ Luijkx T, Gaillard F. "Functional MRI". Radiopaedia. Retrieved 2017-10-16.
- ^ a b "Magnetic Resonance Angiography (MRA)". Johns Hopkins Hospital. Retrieved 2017-10-15.
- ^ Keshavamurthy J, Ballinger R et al. "Phase contrast imaging". Radiopaedia. Retrieved 2017-10-15.