Case Control Study
Copyright ©The Author(s) 2015.
World J Radiol. Nov 28, 2015; 7(11): 405-414
Published online Nov 28, 2015. doi: 10.4329/wjr.v7.i11.405
Table 1 Diffusion tensor imaging-derived tensor metric formulas
MD
MD = D = (λ1 + λ2 + λ3)/3
FA
FA = [(3/2) × (q/L)]1/2 = (3/2)1/2{[(λ1 - D)2+(λ2 - D)2+(λ3 - D)2]/(λ12 + λ22 + λ32)}1/2
RA
RA = q/p = {[(λ1 - D)2 + (λ2 - D)2+(λ3 - D)2]1/2}/[31/2D]
RD
RD = (λ2 + λ3)/2
AD
AD = λ1
Cs
Cs = 3λ3/(λ1 + λ2 + λ3)
p
p = 31/2D = (λ1 + λ2 + λ3)/31/2
q
q = [(λ1 - D)2 + (λ2 - D)2 + (λ3 - D)2]1/2
L
L = (p2 + q2)1/2 = (λ12 + λ22 + λ32)1/2
Cl
Cl = (λ1 - λ2)/(λ1 + λ2 + λ3)
Cp
Cp = 2(λ2 - λ3)/(λ1 + λ2 + λ3)