Chapter 12

Self-assessment Questions

1. What is MR microscopy? What spatial resolution can be achieved?
2. How can multiple-channel acquisition provide improved spatial resolution?
3. How can multiple-channel acquisition provide improved temporal resolution?
4. What are the advantages of using very high-field scanners for spatial resolution of fMRI?
5. How can diffusion tensor imaging provide maps of fiber tracts within the brain?
6. What approaches can be used to minimize susceptibility artifacts on BOLD fMRI images?
7. What are venograms and how are they created? How are they different from angiograms?
8. How can perfusion imaging provide information about brain function?
9. How can maps of diffusion be used to localize MR signal to capillaries?
10. How might using a very high b factor allow measurement of neuronal activity?
11. What is partial k-space imaging? What are the major approaches for partial k-space sampling, and what are their advantages and disadvantages?
12. What is a spiral-in sequence, and why might it be preferred to EPI or spiral-out sequences?
13. How can presenting stimuli at very short interstimulus intervals (i.e., 10 ms) allow fMRI measurement of neuronal interactions with very high temporal resolution?
14. What are Lorentz forces and why do they occur in neurons?
15. How could MRI be used to measure direct neuronal activity using Lorentz Effect Imaging?