Christina A. Chen1, Weitian Chen2, Stuart B. Goodman1, Brian A. Hargreaves1, Kevin M. Koch3, Wenmiao Lu1, Anja C. Brau2, Christie E. Draper1, Scott L. Delp1, Garry E. Gold1
1Stanford University, Stanford, CA, United States; 2GE Healthcare Applied Science Lab, Menlo Park, CA, United States; 3GE Healthcare Applied Science Lab, Milwaukee, WI, United States
We have developed 2 three-dimensional MRI prototypes that correct for metal-induced artifacts, Slice Encoding for Metal Artifact Correction (SEMAC) and Multi-Acquisition Variable-Resonance Image Combination (MAVRIC). In 10 knees with metallic total knee replacements (TKR) scanned at 1.5T, SEMAC and MAVRIC both had significantly less artifact than conventional two-dimensional fast spin echo (FSE). In a model of the knee fitted to a TKR of known dimensions, SEMAC and MAVRIC had much smaller percent deviations from actual component dimensions than FSE, indicating their accuracy in measuring geometry in the presence of metal. MAVRIC and SEMAC are promising MR imaging techniques that may allow for improved musculoskeletal follow-up imaging of metallic implants and soft tissue structures surrounding metal in the knee.