CT and MRI Techniques for Imaging Around Orthopedic Hardware.

Orthopedic hardware impairs image quality in cross-sectional imaging. With an increasing number of orthopedic implants in an aging population, the need to mitigate metal artifacts in computed tomography and magnetic resonance imaging is becoming increasingly relevant. This review provides an overview of the major artifacts in CT and MRI and state-of-the-art solutions to improve image quality. All steps of image acquisition from device selection, scan preparations and parameters to image post-processing influence the magnitude of metal artifacts. Technological advances like dual-energy CT with the possibility of virtual monochromatic imaging (VMI) and new materials offer opportunities to further reduce artifacts in CT and MRI. Dedicated metal artifact reduction sequences contain algorithms to reduce artifacts and improve imaging of surrounding tissue and are essential tools in orthopedic imaging to detect postoperative complications in early stages. KEY POINTS   · Tissues around orthopaedic hardware can still be well visualised despite metal artifacts.. · Artefact reduction in CT: acquisition parameters, iterative reconstruction, Dual-energy CT and VMI.. · Artefact reduction in MRI: choice of device, sequences, acquisition parameters and MARS. CITATION FORMAT · Do TD, Sutter R, Skornitzke S et al. CT and MRI Techniques for Imaging Around Orthopedic Hardware. Fortschr Röntgenstr 2018; 190: 31 - 41.