Box plot of B-mode and strain contrast. Box plot of brightness mode and strain magnitude contrast for the low-grade glioma samples (a) and the high-grade glioma samples (b). The lower and upper edges of the box represent the first and third quartile respectively, while a horizontal line within the box indicates the median. The vertical length of the box represents the interquartile range (IQR). The most extreme sample values (within a distance of 1.5 IQR from the median) are the endpoints of the lines extending from the box. Possible outliers are shown as circles.