Study Guide I - PET Instrumentation

  1. Fundamental concept - are we dealing with photons and gamma rays? (link)
    1. Consider the source
    2. Relate LORs to counts
    3. What is a sinogram?
    4. How does the imaging system coordinate its location, coincident event?
    5. What is TOF? Does it improve image quality? How? (link)
  2. Compare the types of crystals used in PET. Don't need to memorize it, but understand how one is better than the other. (link)
    1. Why is BGO and LSO better than NaI(Tl)?
    2. How do the different principles of a crystal apply to generating the coincident event?
    3. How does TOF fit into the crystal design?
    4. Consider the cuts on a crystal surface. How does it improve the scintillation process?
  3. Consider the crystal's block design (link)
    1. Define the different types.
    2. What are the advantages and disadvantages of each?
  4. Rings (link)
    1. Relate this to the coincident event and its FOV.
    2. Compare 2D vs 3D
    3. What is the role of septa/annular?
    4. How does this prevent scatter and/or random events?
  5. Describe the role of the timing PHA windows. (link)
  6. Define Normalization and Blank scans. What are their roles? (link)
  7. From the scintillation event to the creation of a sinogram, follow the process. Describe it. (link)
  8. Identify PET acquisition as it relates to (link)
    1. Dynamic
    2. Static
    3. Whole body
    4. Gating
    5. List mode
  9. Discuss the role of attenuation correction and apply it to the PET image. Regarding CT consider: (link)
    1. Segmentation
    2. Mono vs polyenergetic photons
    3. Scaling
    4. How does CT correct (or incorrectly correct) a PET image? Consider
      1. Low density attenuation
      2. High density attenuation
      3. Movement and breathing artifacts
  10. Discuss the effects of deadtime in a PET scan (link)
    1. Describe the problem
    2. Consider crystal application and how this should reduces the deadtime issue
  11. Define radial elongation (link)
  12. Know TOF, but don't worry about applying the formula associated with this application (link)
  13. Consider the basics of CT (link)
    1. Refer to the attenuation portion above.
    2. Define HU, windowing, and its effect with a gray scale.
    3. Apply the concept of linear attenuation.
  14. Consider PET resolution(link)
    1. Distance the beta particle travels
    2. Non-collinearity
    3. Components that effect image contrast
      1. Patient motion
      2. Count density
      3. FWHM
      4. A lesion: size, counts, cold, hot, BKG
    4. Effects of scatter
  15. Consider imaging reconstruction (link)
    1. Why is iterative reconstruction (IR) preferred over FBP?
    2. Understand the IR process: OSEM and MLEM.

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