Cerebral aneurysm is one of the major diseases that endanger life and health, and is considered as the high-risk of high-risk procedures in cranial surgery because of the difficulty of surgery and high mortality rate once ruptured. Once detected, intracranial aneurysms usually require surgical treatment, including craniotomy to clip the aneurysm, isolation of the aneurysm, and minimally invasive intervention to embolize the aneurysm. With any of these surgical procedures, a metallic foreign body is implanted into the skull, such as aneurysm clips, cranial fixation staples, microspring coils, vascular stents, etc. Many patients, including radiologists, ask, “Can I still have a head MRI once these materials have been placed?” After all, head MRI can show the anatomy of brain tissue more clearly than head CT. To answer this question, two aspects need to be analyzed, the nature of the material and the field strength of the MRI. With the advancement of technology, the material production process is also progressing. If the material is plastic in nature, it is safe to say that there is no problem doing MRI; the nature of the commonly used material is usually titanium alloy, and at the current level of technology, most of these materials are fully compatible with MRI (the best MRI field strength is not more than 1.5T); for the implant material made of steel, it is not compatible at all. MRI is a contraindication! Therefore, after craniotomy, MRI should be done according to the nature of the specific implant material. Except for the materials made of steel, basically, MRI can be done without worrying about the adverse effects. It should be reminded that before doing so, you must clarify with your own doctor in charge what kind of implant material it is.