The effect of nuclear magnetic resonance imaging on metallic middle ear prostheses.

Nuclear magnetic resonance imaging, a relatively new diagnostic instrument, is a noninvasive imaging method which, among its many advantages, uses no ionizing radiation. There are a few limitations and contraindications to its use. There may be displacement of intracerebral aneurysm clips and metallic implants, and cardiac pacemakers can be disabled because of the high magnetic field created by this device. We studied the effects of a magnetic field on metallic middle ear prosthetics and concluded that nuclear magnetic resonance imaging should offer no risks to hearing or otologic function in patients with nonferromagnetic metallic middle ear prosthetics. Nuclear magnetic resonance imaging is contraindicated in patients with cochlear implants.