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. Author manuscript; available in PMC: 2017 Nov 28.
Published in final edited form as: Invest Radiol. 2016 Aug;51(8):469–482. doi: 10.1097/RLI.0000000000000256

Table 5.

SNR and CNR Summary Statistics (Mean and Standard Deviation Over 2 Readers) and SNR Values Adjusted for Relative Difference in Spatial Resolution (SNR adj)

Volunteers
Patients Analyzed as Volunteers
SNR, Mean SNR, SD CNR, Mean CNR, SD SNR adj SNR, Mean SNR, SD CNR, Mean CNR, SD SNR adj
T1 MP2RAGE 3D 3 T 61.2 18.2 30.8   9.5   61.2 57.0 17.0 29.5 17.5   57.0
7 T 34.8   7.6 17.8   4.7   49.5 35.9   8.3 18.8 10.1   51.2
T2 TSE 2D 3 T 22.0   7.6 12.4   5.5   22.0 21.8   6.7 13.8   7.1   21.8
7 T 16.5   3.9 11.7   3.3   42.9 15.4   5.3 10.5   6.0   40.2
FLAIR TSE 2D 3 T 25.4   7.7 11.6   5.7   25.4 24.2   5.7 11.5   5.8   24.2
7 T 16.8   6.4 11.2   3.7   28.0 17.3 10.3 10.7   8.1   28.9
T2* GRE 3 T 44.8 18.7 10.5   7.7   44.8 40.9 15.3 16.1 18.7   40.9
7 T 22.9   9.8 12.1   6.7 176.4 18.9   5.7 12.1   6.6 145.9
fMRI* 3 T 43.2 11.8 12.2   5.5   43.2
7 T 14.7   3.9 13.3   5.7   73.8
T2 SPACE 3D 3 T 28.1   9.2   4.7   2.6   28.1 23.1   8.6   6.4   9.7   23.1
7 T 33.1   7.3   8.6   4.8   36.7 27.4   9.6 12.4 14.6   30.5
FLAIR SPACE 3D 3 T 29.1 11.0   6.6   3.3   29.1 30.2 11.0   7.3 11.0   30.2
7 T 28.5   7.8 10.4   6.3   63.9 31.6 12.6 13.6 13.8   70.8
DWI single shot 3 T 15.2   2.9   15.2 15.3   2.3   15.3
7 T 22.6   7.5   37.6 18.4   4.8   30.7
DWI RESOLVE 3 T 17.9   3.2   17.9 15.6   3.3   15.6
7 T 12.8   2.3   33.3 11.1   2.4   28.9
T1 FLASH 3 T 94.6 12.2 14.0   3.8   94.6 86.9 24.5 19.7 23.5   86.9
7 T 84.2 31.6 11.8   7.5 175.3 80.3 31.8 13.9 17.9 167.3
DIR SPACE 3D 3 T   8.5   3.3 26.4   7.9     8.5   9.3   4.5 17.0   8.7     9.3
7 T 16.6   5.9 21.0 10.3   33.2 15.7   6.2 16.2 11.8   31.3

Blank spaces indicate no GM/WM contrast.

Results for healthy volunteers (left) and patients analyzed as healthy volunteers, that is, without visible pathology (right).

*

Please note that these volunteers are different than those considered for the remaining 10 sequences, as described in Materials and Methods.

SNR indicates signal-to-noise; CNR, contrast-to-noise ratio; MP2RAGE, magnetization prepared rapid acquisition gradient echo sequence with bias field correction; T2 TSE 2D, 2D turbo spin echo; FLAIR TSE 2D, 2D FLAIR TSE; T2* GRE, T2*-weighted gradient echo sequence; fMRI, functional MRI; T2 SPACE 3D, 3D T2-weighted TSE with variable flip angle; FLAIR SPACE 3D, 3D FLAIR TSE with variable flip angle; DWI single shot, single-shot diffusion-weighted imaging EPI; DWI RESOLVE, multishot readout-segmented diffusion-weighted EPI with 2D navigator correction; T1 FLASH, T1-weighted spoiled gradient echo sequence; DIR SPACE 3D, 3D double inversion recovery TSE with variable flip angle.