. 2022 Jan 5;64(1):42–50. doi: 10.1177/02841851211070119

Table 1.

Calculation of objective lesion parameters.

LLC	$= a v e r a g e a t t e n u a t i o n l i v e r R O I s – a v e r a g e a t t e n u a t i o n l e s i o n R O I$
SNR	$= \frac{a v e r a g e a t t e n u a t i o n l e s i o n R O I}{σ l e s i o n R O I}$
CNR_L	$= \frac{L L C}{σ l i v e r R O I s}$
CNR_BG	$= \frac{L L C}{σ b a c k g r o u n d R O I}$

σ, standard deviation; CNR_BG, contrast-to-noise ratio with background noise; CNR_L, contrast-to-noise ratio with image noise in liver; LLC, liver-to-lesion contrast; ROI, region of interest; SNR, signal-to-noise ratio.