Tattoos with metallic or ferromagnetic color ingredients can distort MR images. Skin irritations or burns caused by heating of the metallic particles due to the radio frequency pulse are also possible, but rare.

Patients should be informed about the possible risk, and scanning should be stopped immediately if they feel heat. Metallic make-up can even be pulled into the eye by magnetic forces and should be removed previous to the MRI scan.

Pacemaker lead wires, ECG, and plethysmographic cables can also as surface-coil connections act as antennae. Usually the materials of such wires are not ferromagnetic.

Gradient and radio frequency fields may induce current into these wires and thus cause fibrillations and burns. This presents a risk to the patient and must be eliminated before the examination. The risk of heating during the MRI scan is dependent on the length and the material of these wires as well as the used field strength. If these wires are outside the RF field there is no risk of heating to expect.