If you have 2D slices in 3 different orientations then you need to load all of them and then show a different image in each slice view (click the pushpin icon in the top-left corner of the slice view to see the image selector widget). You may also want to rotate the view to match the slice orientation, by clicking the small double-arrow button in the slice view controller, and then pressing the “Rotate to volume plane” button. See details here: Read Prostate MR image failed