Fig. 3

A 67-year-old man with primary central nervous system lymphoma. A contrast-enhanced T1-weighted image with a ROI (solid line) (a), a fluid attenuated inversion recovery image with a ROI (dotted line) (b), an ADC map derived from pulsed gradient spin-echo (PGSE) DWI at an effective diffusion time (Δ_eff) of 44.5 ms (c), an ADC map derived from oscillating gradient spin-echo (OGSE) DWI at an Δ_eff of 7.1 ms (d), and maps of the ADC change between PGSE DWI and OGSE DWI (cADC) (e) and the relative ADC change between PGSE DWI and OGSE DWI (rcADC) (f). The ADC values in the tumor appear higher at short Δ_eff values than at long Δ_eff setting. Large changes in the cADC and rcADC are noted between the OGSE and PGSE sequences in the tumor