Fig 1. A cobalt-alloy clip scanned with and without OSHST. A, Control image. B, Second image with OSHST. C, Second image without OSHST. D, Subtraction image (B – A). E, Subtraction image (C – A). The streak artifact generated by the clip is in the same direction as that with OSHST (A and B), and the subtraction image (D) eliminates the artifacts. Subtraction image without OSHST (E) removes the clip itself, but the artifact around the clip remains.