Fig. 2

a Plots showing left and right nerve volumes and maximal cross-sectional areas in individual controls (black shading) and migraineurs (grey shading). Horizontal box plots indicate mean (±SEM) for the left and right nerves of each group. Note that only the volume was significantly different, i.e., lower in the right nerve for both controls and migraineurs. *p < 0.05. b Plots showing fractional anisotropy, mean diffusivity, axial diffusivity and radial diffusivity of the left and right trigeminal root in individual controls and migraineurs. Horizontal box plots indicate mean (±SEM) for the left and right nerves of each group. Note that only fractional anisotropy (FA) and axial diffusivity (AX) was significantly different, i.e., FA was lower in the left nerve of migraineurs than controls and AX was lower in the right nerve than the left nerve in migraineurs. *p < 0.05