Compressed Sensing SEMAC: 8-fold Accelerated High Resolution Metal Artifact Reduction MRI of Cobalt-Chromium Knee Arthroplasty Implants

Objective: The aim of this study was to prospectively test the hypothesis that a compressed sensing–based slice encoding for metal artifact correction (SEMAC) turbo spin echo (TSE) pulse sequence prototype facilitates high-resolution metal artifact reduction magnetic resonance imaging (MRI) of cobalt-chromium knee arthroplasty implants within acquisition times of less than 5 minutes, thereby yielding better image quality than high-bandwidth (BW) TSE of similar length and similar image quality than lengthier SEMAC standard of reference pulse sequences. Materials and Methods: This prospective study was approved by our institutional review board. Twenty asymptomatic subjects (12 men, 8 women; mean age, 56 years; age range, 44–82 years) with total knee arthroplasty implants underwent MRI of the knee using a commercially available, clinical 1.5 T MRI system. Two compressed sensing–accelerated SEMAC prototype pulse sequences with 8-fold undersampling and acquisition times of approximately 5 minutes each were compared with commercially available high-BW and SEMAC pulse sequences with acquisition times of approximately 5 minutes and 11 minutes, respectively. For each pulse sequence type, sagittal intermediate-weighted (TR, 3750–4120 milliseconds; TE, 26–28 milliseconds; voxel size, 0.5 × 0.5 × 3 mm3) and short tau inversion recovery (TR, 4010 milliseconds; TE, 5.2–7.5 milliseconds; voxel size, 0.8 × 0.8 × 4 mm3) were acquired. Outcome variables included image quality...
Source: Investigative Radiology - Category: Radiology Tags: Original Articles Source Type: research