Improved Field Mapping Near Metal
Reducing the noise and distortion in magnetic field maps near metal implants allows for better visualization of the anatomy near the implant. Typical MR images acquired near metal implants are distorted and have areas with no signal near the implant. Multispectral imaging techniques and subsequent correction with a magnetic field map can be used to reduce these artifacts. In this work, we propose a method that improves the magnetic field maps estimated from multispectral data acquired near the implant, and also propose a deblurring technique that reduces the noise and distortion in the field maps relative to previous methods.
Quist B, Shi X, Weber H, Hargreaves BA. Improved field-mapping and artifact correction in multispectral imaging. Magn Reson Med. 2017 Nov;78(5):2022-34.
Relative to the true field map of a simulated digital metal implant phantom (b), the new goodness-of-fit method proposed in this paper to estimate the field map shows less error (d) than the previous center-of-mass method (c).
Xinwei Shi, Brady Quist, and Hans Weber are alumni of the BMR group