A novel method for quantifying scanner instability in fMRI.

Journal Article

A method was developed to quantify the effect of scanner instability on functional MRI data by comparing the instability noise to endogenous noise present when scanning a human. The instability noise was computed from agar phantom data collected with two flip angles, allowing for a separation of the instability from the background noise. This method was used on human data collected at four 3 T scanners, allowing the physiological noise level to be extracted from the data. In a "well-operating" scanner, the instability noise is generally less than 10% of physiological noise in white matter and only about 2% of physiological noise in cortex. This indicates that instability in a well-operating scanner adds very little noise to functional MRI results. This new method allows researchers to make informed decisions about the maximum instability level a scanner can have before it is taken off line for maintenance or rejected from a multisite consortium. This method also provides information about the background noise, which is generally larger in magnitude than the instability noise.

Full Text

Duke Authors

Cited Authors

  • Greve, DN; Mueller, BA; Liu, T; Turner, JA; Voyvodic, J; Yetter, E; Diaz, M; McCarthy, G; Wallace, S; Roach, BJ; Ford, JM; Mathalon, DH; Calhoun, VD; Wible, CG; Brown, GG; Potkin, SG; Glover, G

Published Date

  • April 2011

Published In

Volume / Issue

  • 65 / 4

Start / End Page

  • 1053 - 1061

PubMed ID

  • 21413069

Pubmed Central ID

  • 21413069

Electronic International Standard Serial Number (EISSN)

  • 1522-2594

International Standard Serial Number (ISSN)

  • 0740-3194

Digital Object Identifier (DOI)

  • 10.1002/mrm.22691


  • eng