What are the dangers caused by a brain mri?

MR imaging is safe: There are no inherent dangers caused by the magnetic field on the brain. However, a number of items can interfere with mr imaging and some may be hazardous, these include older brain aneurysm clips, cardiac pacemakers/aicd/defibrillators, implanted medicine pumps, tens unit, bullet fragments/pellets/shrapnel, embolization coils, etc. Claustrophobic patients find MRI difficult to without medication.

None: They will give you screening form to assess for any possible contraindications but assuming three are none, its very very safe.