Summary
I’ve updated my stability scan summary code to bring all the measures into a single plot. Hopefully it’s not too busy. Details on stability scans below. My last post explained the bimodal distribution of the “Mean ghost” measure for the 64-channel coil.
Details:
Weekly MRI quality assurance (QA) scans are performed with the 64-, 32-, and 20-channel head coils. Scan sequences are based on recommendations of Pyles et al. (see https://sites.google.com/view/mri-facility-qa) and stability measures are calculated using the Functional Imaging Federated Informatics Research Environment (FBIRN) QA metrics. Metrics include signal-to-noise ratio (SNR), signal-to-fluctuation noise ratio (SFNR), and mean ghost percentage.
Scan sequences include:
- 64ch coil, CMRR Warmup
- 64ch coil, Siemens Grappa=2
- 64ch coil, CMRR MB=3
- 64ch coil, Siemens Basic
- 64ch coil, CMRR MB=3, ACPC aligned
- 32ch coil, Siemens Standard
- 32ch coil, Siemens Basic
- 32ch coil, CMRR MB=3
- 32ch coil, CMRR MB=3, ACPC aligned
- 20ch coil, Siemens Standard
- 20ch coil, CMRR MB=3
- 20ch coil, CMRR MB=3, ACPC aligned
(NB: occasionally I’ll run a subset of these if time does not permit collecting every scan sequence. This accounts for the missing data points in the graphs above.)