Table 1. Summary of human MRI/DTI studies in NF1 (ADC, apparent diffusion coefficient; λ1, longitudinal diffusivity; λ2 and λ3, transverse diffusivity).

Authors	WM volume	GM volume	Brain volume	ADC	MD	FA	RD	λ2, λ3	λ1
Cutting et al. (2000)			H
Moore et al. (2000)	H*	H	H
Steen et al. (2001)	H	ND	H
Cutting et al. (2002)	H	H/L	H
Greenwood et al. (2005)	H	H	H
Margariti et al. (2007)	H	H
Zamboni et al. (2007)				H		L
Wignall et al. (2010)	H*		H			L*		H*	ND*
Santos (2011)					H*	L*		H*	ND*
Filippi et al. (2013)			ND		H	L†	H†		ND†
Karlsgodt et al. (2012)	H	H		H		L	H		H
Duarte et al. (2014)	H	H/L
Pride et al. (2014)	ND	H/L	H

H, higher values in NF1 patients compared to control subjects; L, lower values in NF1 patients compared to control subjects; H/L, H and L were obtained for different brain regions; ND, no differences between NF1 patients and control subjects.

^*Observations restricted to visual-callosal WM pathways.

^†Observations restricted to the corpus callosum.