Cranial MRI, also known as cranial magnetic resonance imaging, can detect more lesions, as follows: 1, the most used in ischemic cerebrovascular disease, generally can detect acute infarct foci within 6 hours of onset; 2, can distinguish old or fresh infarct foci, providing effective imaging basis for clinicians’ treatment; 3, in terms of brain tumors, MRI also plays an important role, such as glioma, meningioma, metastases MRI also plays an important role in brain tumors, such as gliomas, meningiomas, metastases, and other common tumors, and MRI can generally provide clinically accurate diagnosis with its multi-directional and multi-sequence imaging sequences; 4, MRI also has great advantages in vascular malformations, poisoning and metabolic brain diseases. MRI is not disturbed by the skull compared with CT, and is significantly better than CT in showing brainstem and cerebellar lesions. in addition, the resolution of MRI for fine structures is significantly higher than CT, which is the reason for the diagnosis of brain tumors and metabolic diseases, and vascular malformations of choice.