Iima M, et al. - Via a prospective study on 31 consecutive patients with suspected head and neck tumors and a phantom, the researchers investigated the change in utility of apparent diffusion coefficient (ADC) value to distinguish between the malignant and benign head and neck tumors using the different diffusion times received from oscillating gradient spin-echo (OGSE) and pulsed gradient spin-echo (PGSE) MRI sequences. In comparison to the ADC values obtained with OGSE, a lower PGSE sequence was obtained. As revealed by changes in diffusion time, the difference was larger for malignant vs benign tumors, inferring differences in tissue structure (diffusion hindrance) or cell permeability. Hence, for interpretation of head and neck diffusion MRI, the study exhibits the potential importance of reporting diffusion time.