Improving MRI contrast : Magnetization transfer

Improving MRI contrast : Magnetization transfer

by Denis Hoa

Learning objectives

After reading this chapter, you should be able:

  • To present the different fat signal suppression techniques
  • Describe the advantages and disadvantages of STIR sequences, fat saturation, selective excitation of water
  • Specify the different families of contrast agents
    • Explain their action on relaxation time and contrast
    • List their contraindications and main indications
  • Explain magnetization transfer and how it can improve background suppression

Key points

Magnetization transfer

  • Off-resonance RF pulse in relation to the peak of water
  • Saturation of protons with restricted mobility (brain, muscle, liver)
  • Drop in signal due to exchanges between free and bound protons
  • Does not affect fluids (LCR, blood, urine) containing no bound protons

References

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