Ultra-high field MRI (3 teslas and more)
After reading this chapter, you should be able:
- To state the consequences of increasing the magnetic field on signal-to-noise ratio, relaxation times, SAR, artifacts, acoustic noise
- Describe the necessary adaptations in sequence parameters and equipment
- Set out the advantages and disadvantages of increasing magnetic field
- List the potential fields of application of ultra high field MRI
3,0 T vs|
|Advantages & Applications||Disadvantages & Solutions|
↑ image quality|
↑ spatial resolution
|T1||↑ ~|| |
↑ blood/tissue contrast
↑ TR or ↓ signal
Magnetization preparation (inversion, MP…)
Drop in signal
RF energy deposited (SAR limit)
|Chemical shift||↑|| |
↑ differences in resonance frequency
Better fat suppression
Chemical shift artifacts
|Magnetic susceptibility||↑↑|| |
Greater sensitivity to magnetic susceptibility
Better detection of hemorrhages
Magnetic susceptibility artifacts
|Dielectric effects||↑||↑|| |
RF heterogeneities, variable signal loss in the image
Optimization of coils,
Vacuum magnet housing|
Headphones, gradient downgrade
- Willinek and Kuhl. 3.0 T neuroimaging: technical considerations and clinical applications. Neuroimaging clinics of North America. 2006 May;16(2):217-28, ix.
- Tanenbaum. Clinical 3T MR imaging: mastering the challenges. Magnetic resonance imaging clinics of North America. 2006 Feb;14(1):1-15.
- Heidemann, Seiberlich. Perspectives and limitations of parallel MR imaging at high field strengths. Neuroimaging clinics of North America. 2006 May;16(2):311-20, xi.
- Voss, Zevin. Functional MR imaging at 3.0 T versus 1.5 T: a practical review. Neuroimaging clinics of North America. 2006 May;16(2):285-97, x.
- Merkle and Dale. Abdominal MRI at 3.0 T: the basics revisited. Ajr. 2006 Jun;186(6):1524-32.
- Mosher. Musculoskeletal imaging at 3T: current techniques and future applications. Magnetic resonance imaging clinics of North America. 2006 Feb;14(1):63-76.
- Gutberlet, Noeske. Comprehensive cardiac magnetic resonance imaging at 3.0 Tesla: feasibility and implications for clinical applications. Investigative radiology. 2006 Feb;41(2):154-67.
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