MRI has a high resolution for the nervous system and soft tissues, and can be used for most systemic diseases except respiratory system, such as various tumor diseases, inflammatory diseases, degenerative changes, and vascular diseases. It is also suitable for cervical and lumbar spine and other systemic bone and joint diseases, as well as abdominal, pelvic and breast diseases. MRI has a variety of functional imaging, such as water imaging, vascular imaging, biliary tract imaging, diffusion-weighted imaging, perfusion-weighted imaging, etc., and is used in an increasingly wide range of applications.