Fig. 4.

ADC measurements with increasing diffusion times to investigate restriction. A and B: Diffusional signal decays in WAT and BAT with different diffusion times (Δ) are shown. The field gradient pulse width (δ/2) and the polarization changing delay (τ) were fixed to 5 and 0.5 ms, respectively. As the diffusion time was increased, a clear upward drift in the signal decay curves was seen, in the case of BAT only, and the WAT data nearly overlap, by contrast. A similar trend was observed at 36°C (data not shown). ADC corresponding to variable diffusion times was calculated with equation 1. C and D: Reduction of fat ADC with increasing diffusion time was much more significant for BAT compared with WAT.