Purpose: To evaluate the magnetic field interactions with Yasargil aneurysm clips exposed to a 1.5-T MR system.
Materials and methods: Sixteen Yasargil aneurysm clips made with Phynox (10 clips returned to the manufacturer due to suspected magnetic field interactions and six clips obtained from the manufacturer in sterile packages) were tested for magnetic field interaction at 1.5 T by using techniques to assess magnetic field-induced translational (deflection angle test) and torque (changes in alignment or rotation) forces.
Results: None of the aneurysm clips demonstrated magnetic field interactions; that is, deflection angles were zero and there were no changes in alignment or evidence of rotational forces present.
Conclusion: It is safe to perform MR procedures at 1.5 T or less in patients with Yasargil aneurysm clips made with nonferromagnetic material.