Magnetic resonance imaging of cerebral infarction is not exactly the same in different periods. In the acute phase, the MRI scan shows a low signal shadow in the T1 phase and a high signal shadow in the T2 phase, and in the chronic phase, it is also the same. Patients with cerebral infarction show low signal shadow in the acute phase and high signal shadow in the chronic phase, while patients with encephalitis and multiple sclerosis show low signal shadow in the ADC, which is an important key point for differentiation from cerebral infarction. Patients with cerebral infarction have different imaging manifestations in different periods of infarction.