The difference between CT and MRI is mainly divided into the following points: 1) the two imaging principles are different, CT uses X-rays to sweep the body in cross-section, while MRI uses an applied magnetic field to sweep various parts of the body. 3, the focus of the examination is different, CT for density resolution is relatively high, so for head diseases, lung diseases and skeletal system diseases have a unique diagnostic value, while MRI for soft tissue resolution is relatively high; 4, the price is different, CT price is generally in about 200 yuan, while MRI is generally in about 500 yuan.