Table 2.
Models tested with fit parameters in parentheses.
| Model | Vascular | Extracellular | Intracellular | No. parametersa |
|---|---|---|---|---|
| Apparent diffusion coefficient (ADC) | Ball (ADC) | 3 | ||
| Intravoxel incoherent motion | Ball (fp, Dp) | Ball (ft, Dt) | 4 | |
| Kurtosis | Kurtosis (Dkurt, K) | 4 | ||
| Astrosticks–Ball–Sphere | Astrosticks (fp, Dp) | Ball (fE, DE) | Sphere (fI, DI, R) | 6 |
| Ball–Ball–Sphere | Ball (fp, Dp) | Ball (fE, DE) | Sphere (fI, DI, R) | 6 |
| Ball–Astrosticks–Sphere | Ball (fp, Dp) | Astrosticks (fE, DE) | Sphere (fI, DI, R) | 6 |
Total number of fit parameters summarized in the last column.
aNumber of model parameters includes normalization constant (S0) and T2 decay time constant (T2). Additional constraints: Dp = 1 × 10−2 mm2/s, DE = DI < 3 × 10−3 mm2/s, ∑fj = 1.