Glen Morrell1, Joshua Kaggie2,
K. C. Goodrich2, Seong-Eun Kim2, Sung Man Moon2,
Dennis Parker2
1Radiology, University of
Utah, Salt Lake City, UT, United States; 2Utah Center for Advanced
Imaging Research, Salt Lake City, UT, United States
We demonstrate a method of mapping the field patterns of insert gradient coils in a composite gradient system. Composite gradient systems allow the simultaneous use of whole body gradient coils and localized insert gradient coils within the same pulse sequence. These systems combine the speed of nonlinear local insert gradient coils for readout with the desirable linearity of slower whole body gradients for slice selection. Correction of image distortion requires accurate maps of the nonlinear insert gradient fields used for readout. Our method provides distortion-free maps of the gradient insert fields over the entire imaging volume in reasonable imaging time