Ct scan, mri, nuclear medicine imaging, ivp scan, how are they different?

Quite different. Ct involves xray type radiation with cross sectional imaging in transaxial, sagittal, and coronal projections. Nuclear medicine, internal irradiation either injected intravenously, inhaled, ingested, injected subcutaneously.Ivp uses injection of contrast material for visualization of kidneys and bladder with x-ray. Mr imaging uses no ionizing radiation magnetic fields to generate x-sectional images.