MRI sequences

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Author: Mikael Häggström [notes 1]

Sequences

Group Sequence Abbr. Main clinical distinctions Example
Spin echo T1 weighted T1
  • Lower signal for more water content, [1]as in edema, tumor, infarction, inflammation, infection, hyperacute or chronic hemorrhage [2]
  • High signal for fat[1][2]
  • High signal for paramagnetic substances, such as MRI contrast agents[2]

Standard foundation and comparison for other sequences

T1-weighted-MRI.png
T2 weighted T2
  • Higher signal for more water content[1]
  • Low signal for fat[1]
  • Low signal for paramagnetic substances[2]

Standard foundation and comparison for other sequences

Normal axial T2-weighted MR image of the brain.jpg
Proton density weighted PD Joint disease and injury.[3]
  • High signal from meniscus tears[4] (pictured)
 Proton density MRI of a grade 2 medial meniscal tear.jpg
Gradient echo Steady-state free precession SSFP Creation of cardiac MRI videos (pictured).[5] Four chamber cardiovascular magnetic resonance imaging.gif
Inversion recovery Short tau inversion recovery STIR High signal in edema, such as in more severe stress fracture[6] Shin splints pictured: Shinsplint-mri (crop).jpg
Fluid-attenuated inversion recovery FLAIR High signal in lacunar infarction, multiple sclerosis (MS) plaques, subarachnoid haemorrhage and meningitis (pictured).[7] FLAIR MRI of meningitis.jpg
Double inversion recovery DIR High signal of multiple sclerosis plaques (pictured)[8] Axial DIR MRI of a brain with multiple sclerosis lesions.jpg
Diffusion weighted (DWI) Conventional DWI High signal within minutes of cerebral infarction (pictured).[9] Cerebral infarction after 4 hours on DWI MRI.jpg
Apparent diffusion coefficient ADC Low signal minutes after cerebral infarction (pictured)[10] Cerebral infarction after 4 hours on ADC MRI.jpg
Diffusion tensor DTI
  • Evaluating white matter deformation by tumors[11]
  • Reduced fractional anisotropy may indicate dementia[12]
 White Matter Connections Obtained with MRI Tractography.png
Perfusion weighted (PWI) Dynamic susceptibility contrast DSC In cerebral infarction, the infarcted core and the penumbra have decreased perfusion (pictured).[13] Tmax by MRI perfusion in cerebral artery occlusion.jpg
Dynamic contrast enhanced DCE
Arterial spin labelling ASL
Functional MRI (fMRI) Blood-oxygen-level dependent imaging BOLD Localizing highly active brain areas before surgery[14] 1206 FMRI.jpg
Magnetic resonance angiography (MRA) and venography Time-of-flight TOF Detection of aneurysm, stenosis, or dissection[15] Mra-mip.jpg
Phase-contrast magnetic resonance imaging PC-MRA Detection of aneurysm, stenosis and dissection (pictured)[15] Vastly undersampled Isotropic Projection Reconstruction (VIPR) Phase Contrast (PC) sequence MRI of arterial dissections.jpg
Vastly undersampled Isotropic Projection Reconstruction (VIPR)
Susceptibility-weighted SWI Detecting small amounts of hemorrhage (diffuse axonal injury pictured) or calcium[16] Susceptibility weighted imaging (SWI) in diffuse axonal injury.jpg

Notes

  1. ↑ For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Radlines:Authorship for details.

References

  1. ↑ 1.0 1.1 1.2 1.3 . Magnetic Resonance Imaging. University of Wisconsin. Retrieved on 2016-03-14.
  2. ↑ 2.0 2.1 2.2 2.3 Keith A. Johnson. Basic proton MR imaging. Tissue Signal Characteristics. Harvard Medical School. Archived from the original on 2016-03-05. Retrieved on 2016-03-14.
  3. ↑ Jeremy Jones and Prof Frank Gaillard et al.. MRI sequences (overview). Radiopaedia. Retrieved on 2017-01-13.
  4. ↑ Lefevre, Nicolas; Naouri, Jean Francois; Herman, Serge; Gerometta, Antoine; Klouche, Shahnaz; Bohu, Yoann (2016). "A Current Review of the Meniscus Imaging: Proposition of a Useful Tool for Its Radiologic Analysis ". Radiology Research and Practice 2016: 1–25. doi:10.1155/2016/8329296. ISSN 2090-1941. 
  5. ↑ Dr Tim Luijkx and Dr Yuranga Weerakkody. Steady-state free precession MRI. Radiopaedia. Retrieved on 2017-10-13.
  6. ↑ Ferco Berger, Milko de Jonge, Robin Smithuis and Mario Maas. Stress fractures. Radiopaedia. Retrieved on 2017-10-13.
  7. ↑ . Fluid attenuation inversion recoveryg. radiopaedia.org. Retrieved on 2015-12-03.
  8. ↑ Dr Bruno Di Muzio and Dr Ahmed Abd Rabou. Double inversion recovery sequence. Radiopaedia. Retrieved on 2017-10-13.
  9. ↑ Dr Yuranga Weerakkody and Prof Frank Gaillard et al.. Ischaemic stroke. Radiopaedia. Retrieved on 2017-10-15.
  10. ↑ An, H.; Ford, A. L.; Vo, K.; Powers, W. J.; Lee, J.-M.; Lin, W. (2011). "Signal Evolution and Infarction Risk for Apparent Diffusion Coefficient Lesions in Acute Ischemic Stroke Are Both Time- and Perfusion-Dependent ". Stroke 42 (5): 1276–1281. doi:10.1161/STROKEAHA.110.610501. ISSN 0039-2499. 
  11. ↑ Derek Smith and Dr Usman Bashir. Diffusion tensor imaging. Radiopaedia. Retrieved on 2017-10-13.
  12. ↑ Chua, Terence C; Wen, Wei; Slavin, Melissa J; Sachdev, Perminder S (2008). "Diffusion tensor imaging in mild cognitive impairment and Alzheimerʼs disease: a review ". Current Opinion in Neurology 21 (1): 83–92. doi:10.1097/WCO.0b013e3282f4594b. ISSN 1350-7540. 
  13. ↑ Chen, Feng (2012). "Magnetic resonance diffusion-perfusion mismatch in acute ischemic stroke: An update ". World Journal of Radiology 4 (3): 63. doi:10.4329/wjr.v4.i3.63. ISSN 1949-8470. 
  14. ↑ Dr Tim Luijkx and Prof Frank Gaillard. Functional MRI. Radiopaedia. Retrieved on 2017-10-16.
  15. ↑ 15.0 15.1 . Magnetic Resonance Angiography (MRA). Johns Hopkins Hospital. Retrieved on 2017-10-15.
  16. ↑ Dr Bruno Di Muzio and A.Prof Frank Gaillard. Susceptibility weighted imaging. Retrieved on 2017-10-15.
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