We have applied phase image-based motion detection (PITA-MDD) in real-time prospective motion detection and re-acquisition. During image reconstruction, PITA-MDD motion detection is performed on each slice. A diffusion-weighted volume will be re-acquired if number of motion slices exceeds the pre-set threshold. dMRI data were acquired on a volunteer using a prospective PITA-MDD sequence for the brain and the tongue. The detected motion corrupted data were consistent with subject’s motion. Denser tongue muscle fibers were visible after replacing motion volumes with re-acquired volumes. Prospective PITA-MDD motion detection and re-acquisition has improved dMRI acquisition, especially in challenging areas, such as the tongue.