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Motion Quality Control (QC) Manual

Alyssa Dai edited this page Aug 19, 2022 · 2 revisions

Motion quality control (QC) for structural T1 scans

This guide will help you rate your scans for the amount of motion present, and decide which ones to include in your analysis. See also the wiki page on Display, which is the tool we use to visualize .mnc MRI volumes for things like QC (screenshots below).

4 point scale:

  1. Perfect/clean scan
  2. Slight motion (slight ringing or blurring, and/or only in a confined area)
  3. Obvious motion (obvious or bad ringing or blurring, and/or over whole brain)
  4. Very bad motion -- (this will be very obvious, eg. can’t even tell it’s a brain) -- (the difference between 3 and 4 is not that important, because they are both a fail. 4 is more just to highlight if it’s a really really terrible scan)

Notes:

  • Can give .5s (eg 1.5, 2.5) if not sure.
  • I try to avoid this but it’s often hard to decide - it can also be good to have a detailed account of the quality of each scan
    • eg. 1.5 is if it is almost perfect but not quite.
  • The cut off you use is up to you; for a pretty strict cut off, I would recommend including anything in the analysis that is < 2 (ie. 1.5 or 1); or 2 and below if you are being a bit less strict.
  • If in doubt, a good question to keep in mind: “would you be embarrassed to show this scan in your supplemental material?”
    • (if yes, I usually go for at least 2.5 or 3) - I find this helps!
  • It’s important (and helpful) to look at all views of the scan; often rings are easier to see in the coronal view; sometimes they will be barely visible in the sagittal but obvious in coronal view
  • Screenshot examples included below, but it is a bit hard to tell from the image, you need to scroll through all slices of the scan and look at different views.

Things to look out for:

Ringing

  • Ex:

MAX_MUN_51348_4-1

Blurring

  • Ex:

MAX_MUN_51349_3-1

Examples of each QC level:

  • 1

1_1 1_2

  • 1.5

1 5_1 1 1 5_1 2 1 5_1 3

  • 2

KKI_29415_2-1 MAX_MUN_51344_2-1 OHSU_50153_2-1 PITT_50035_2-1 USM_29053_2-1

  • 2.5

PITT_50013_2 5-1 TO_005_2 5-1 UCLA_51304_2 5-1

  • 3

MAX_MUN_51349_3-1 NYU_50957_3-1 TO-437_3-1

  • 4

YALE_50618_4-1 SDSU_50185_4-1 TO_328_4-1

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