Table 1.

Group-Averaged Diffusion Parameters at T9 in the Control Spinal Cords

	Segment	Asd	AI	p	λ⊥ (μm2/ms)	D⊥ (μm2/ms)	p	λ‖ (μm2/ms)	D‖ (μm2/ms)	p
VLWM	T8	0.70 ± 0.02	0.73 ± 0.04	< 0.05	0.28 ± 0.03	0.29 ± 0.04	0.59	2.07 ± 0.10	1.84 ± 0.14	<0.01
	T9	0.71 ± 0.02	0.75 ± 0.03	< 0.05	0.26 ± 0.02	0.26 ± 0.03	0.45	2.01 ± 0.07	1.80 ± 0.11	<0.01
	T10	0.71 ± 0.02	0.74 ± 0.02	<0.05	0.24 ± 0.03	0.25 ± 0.03	0.19	1.93 ± 0.09	1.73 ± 0.08	<0.01
GM	T8	0.26 ± 0.04	0.26 ± 0.04	0.99	0.55 ± 0.06	0.57 ± 0.04	0.29	1.07 ± 0.08	0.98 ± 0.08	<0.05
	T9	0.22 ± 0.03	0.24 ± 0.05	0.37	0.59 ± 0.04	0.59 ± 0.04	0.97	1.03 ± 0.07	0.96 ± 0.08	<0.05
	T10	0.21 ± 0.03	0.17 ± 0.03	<0.05	0.58 ± 0.04	0.60 ± 0.04	0.14	0.95 ± 0.05	0.85 ± 0.04	<0.01
VLWM/GM	T8	2.75 ± 0.36	2.84 ± 0.31	0.45	0.45 ± 0.11	0.50 ± 0.05	0.16	1.94 ± 0.10	1.88 ± 0.13	0.16
	T9	3.28 ± 0.42	3.27 ± 0.59	0.96	0.39 ± 0.09	0.45 ± 0.05	0.06	1.95 ± 0.09	1.87 ± 0.11	0.07
	T10	3.56 ± 0.54	4.55 ± 0.68	<0.01	0.39 ± 0.10	0.42 ± 0.04	0.89	2.04 ± 0.06	2.04 ± 0.06	0.27

The data were obtained from the manually segmented VLWM and GM.

Diffusion indices were derived using DTI and DWI data from the control cords of the manually defined VLWM and gray matter ROIs. Values (mean ± SD) were obtained from all three slices of each vertebral segment. Statistical analysis was performed using a two-tailed, paired Student's t-test with a confidence interval of 95%. The p value indicates the level of statistical difference between diffusion indices obtained from six-direction DTI and two-direction DWI.