Fat-Suppressed and Distortion-Corrected MRI Near Metallic Implants

Introduction: The use of orthopedic implants including joint replacements and fixation devices is increasingly common, necessitating follow-up evaluation to assess possible complications such as loosening or infection. Due to metal-induced distortion and other artifacts on conventional MRI, follow-up is often limited to Xray images. With additional encoding and parallel imaging, MR images with minimal distortion can be acquired in subjects with metallic implants in reasonable scan times [1,2]. Here we achieve distortion-corrected imaging with fat suppression by integrating short TI inversion recovery (STIR) [3] with slice-encoding for metal artifact reduction (SEMAC) [2]. STIR offers fat suppression that is insensitive to susceptibility variations, so it is a robust choice for fat suppression near metal.