Brian A. Hargreaves1, Garry
1Radiology, Stanford
University, Stanford, CA, United States; 2Electrical Engineering,
Stanford University, Stanford, CA, United States; 3Applied Science
Lab, General Electric Healthcare, Waukesha, WI, United States
Metallic implants cause large, varying shifts in resonanct frequency that cause signal loss, distortion, and pile-up artifacts in MR images. The origin of different distortion artifacts is due to the use of frequency-selective excitation and imaging, and can be explained intuitively. Similarly, the mechanisms of various correction techniques such as high-bandwidth, view-angle tilting and additional phase-encoding are graphically demonstrated. Examples of artifacts and different types of correction are shown for different types of metallic implants in different anatomic locations.
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