Enhancing fluid signal in short-TR, STIR-prepared Slice Encoding for Metal Artifact Correction (SEMAC) imaging of a total hip arthroplasty.

Motivation: Acquisition times of metal artifacts reduction sequences, like Slice-Encoding-for-Metal-Artifact-Correction (SEMAC), can be long - particularly in configurations that allow a sensitive detection of fluids, e.g. effusions surrounding loosened implants. Goal(s): To accelerate STIR-prepared SEMAC imaging while preserving its fluid sensitivity. Approach: Extension of a SEMAC sequence with a modified driven equilibrium (DE) module. The effect on fluid signal and image contrast was investigated in a metal phantom with fluid. Results: Fluid signal was increased by 100 % with the modified DE compared to a conventional implementation. TR could be reduced from 3500 to 2000 ms while retaining 97 % of fluid signal. Impact: This innovation promises to improve the diagnostic accuracy in assessing patients with loosened implants by shortening scan times of Slice Encoding for Metal Artifact Correction (SEMAC) sequences under preservation of fluid-signal intensity while providing even increased fluid-tissue contrast.