Figure 4.

(A) ADC maps of a representative slice through tumor and a water phantom at frequencies ranging from 0 to 350 Hz, overlaid on T2-weighted MR images. The water phantom was placed beneath the mouse to monitor the accuracy and consistency of ADC measurements. (B) Representative ADC values of an OVCAR-8 tumor at day 0 (nontreated) and day 4 (Nab-paclitaxel–treated) obtained using TDS and conventional PGSE acquisitions at frequencies ranging from 0 to 350 Hz. Solid lines represent the fits using Eqs. (1), (2), (3). The fitted parameters for nontreated (blue) and Nab-paclitaxel–treated (red) OVCAR-8 are d = 5.92 μm, D_inf = 1.58 μm²/ms, and D₀ = 0.47 μm²/ms and d = 9.22 μm, D_inf = 1.36 μm²/ms, and D₀ = 0.37 μm²/ms, respectively. It is noted that the ADC measured using PGSE with a diffusion time of 48 milliseconds is plotted as the ADC at a corresponding frequency of 5.2 Hz.