To compare the image quality of the reduced field-of-view (rFOV) diffusion-weighted imaging (DWI) with the full field-of-view (fFOV) DWI in the assessment of bladder cancer (BC); and to explore the possible superiority of bi-planar (axial and sagittal) rFOV DWI over single planar fFOV DWI in predicting muscle-invasiveness of BC.