Figure 3.

Signal attenuation and the fitting curves as a function of b* for the three specific ROIs in white matter (WM), gray matter (GM), and the cerebrospinal fluid (CSF) indicated in Fig. 2. (a) Results from the Stejskal-Tanner pulse sequence where b* is defined as b* = (γG_dδ)²[Δ – (2β −1)δ/(2β +1)], and (b) results from the TRSE sequence in which b* is given by $b^{\ast }={\left[\gamma G_d\right({\delta }_1+{\delta }_2\left)\right]}^2\left[\right({\delta }_1^{2\beta }+{\delta }_2^{2\beta })∕({\delta }_1+{\delta }_2){}^{2\beta }({\Delta }^{\prime }-({\delta }_1+{\delta }_2)∕2)+2({\delta }_1+{\delta }_2)∕(2\beta +1)]$. In CSF, only images with b < 1,000 s/mm² were used in the fitting due to inadequate SNR in images with higher b-values.