Fig. 4From: Noninvasive assessment of age-related stiffness of crystalline lenses in a rabbit model using ultrasound elastographyBox-line plot of: a maximum displacement; and b group velocity for group N1 (60 days), N2 (90 days), N3 (120 days), and N4 (150 days). Asterisk indicates that the mean values of the two groups are significantly different (p < 0.001)Back to article page