CT and MR imaging artifacts produced by stainless steel, titanium, and polymer surgical clips and staples

To determine the effect of metal and polymer surgical clips and staples on CT and MR image quality, the authors obtained images of the implants in water and gelatin phantoms and muscle and brain tissue. Deflection angles were measured; the deflection force associated with steel devices of 1.89 T was six times that associated with titanium. Stainless steel staples produced artifacts on CT, while titanium and polymer did not. At 0.14 T, MR imaging artifacts were seen with steel but not titanium or polymer implants. At 1.89 T, distortion was caused by all stainless steel staples and the largest titanium staples, but not by polymer clips