Aneurysm clips: assessment of magnetic field interaction associated with a 0.2-T extremity MR system

Twenty-two different aneurysm clips were tested by means of the deflection angle test for magnetic field interaction associated with a 0.2-T extremity magnetic resonance (MR) system. At the opening of the magnet bore and 5 inches (13 cm) and 10 inches (25 cm) away from the magnet bore, respectively, deflection angles were 14 degrees, 2 degrees, and 0 degree for one clip and were 17 degrees, 4 degrees, and 0 degree for another, and were 0 degree for the remaining 20 clips. Because the patient's head does not enter the magnet bore, extremity MR imaging of patients with the aneurysm clips evaluated in this study should be safe.