Han BH, et al. - This research was formulated in order to investigate the utility of testicular volume, apparent diffusion coefficient (ADC), and normalized ADC estimated via MRI for speculating the histopathologic grade of azoospermia and for differentiating obstructive from nonobstructive azoospermia. Data disclosed markedly greater testicular volume in patients with obstructive azoospermia than in patients with nonobstructive azoospermia. Additionally, it was determined that testicular ADC and normalized ADC were considerably lower in patients with obstructive azoospermia compared to subjects with nonobstructive azoospermia. Therefore, testicular volume, ADC, and normalized ADC proved to be useful in predicting the histopathologic grade and in differentiating obstructive from nonobstructive azoospermia.