Healthy and cancerous brain ADC: diffusion- and echo time dependence with pulsed gradient spin-echo (PGSE) diffusion imaging

Clinical systems vary widely in their gradient performance. Accordingly, effective diffusion time and echo time, which are minimized by the system software according to available gradient performance, can differ significantly among systems. A major concern is that non-Gaussian diffusion in tissues can lead to significant variation of the measured apparent diffusion coefficient (ADC), which would clearly diminish its value as biomarker. This study evaluated if diffusion and/or echo time variations in pulsed gradient spin-echo (PGSE) sequences significantly influences the ADC measured in healthy brain and brain tumors.