GRE signal, contrast & CNR app

For those who prefer an app-style tool that works equally well on mobile devices. Try the new Signal, contrast & CNR for gradient echo calculator.

Page: MAIN1. Select tissue types from the drop down menus.
2. Vary the TR, TE and flip angle. Use sliders, increment with arrows or enter numerical values.
3. Read the normalised signal intensities, contrast and relative SNR.
T1, T2 and M0 (proton density) for each tissue are indicated. Water/fat in-phase, out-of-phase indicated for relevant TE.
Page: GRAPHICView the normalised signal intensities, contrast and relative SNR in a graph
whilst you vary the flip angle, TR and TE.
Note: the value scale adjusts to fit the screen, so always read the numerical values.
Page: DETAILShows tissue Ernst angles for optimum signal for the selected TR. Investigate the effect of B0 inhomogeneity on signals, contrast and relative CNR. Tissue T2* values are shown.

For those who prefer a spreadsheet-style click here.

Disclaimer: this is not a medical device. For educational purposes only. Tissue values may differ from those used. Tissue values from the MRI literature for scanning at 1.5 T only.

© 2021 Donald W McRobbie