1. A magnetic resonance (MR) imaging apparatus, comprising: an application region calculating unit configured to automatically calculate a prepulse application region based on previously acquired MR pilot image data including a region of interest of an object, said automatically calculated prepulse application region having position, thickness and prepulse direction parameters which vary as a function of the region of interest; and an MR imaging unit configured to perform diagnostic magnetic resonance imaging (MRI) of the region of interest of the object including application of the automatically calculated prepulse in a diagnostic MRI data acquisition sequence.