Abstract #3802

Rapid Re-Shimming for Rotated Views in MR-SPECT Imaging

Mark Jason Hamamura¹, Seunghoon Ha¹, Werner W. Roeck¹, Orhan Nalcioglu^1,2

¹Tu & Yuen Center for Functional Onco-Imaging, University of California, Irvine, CA, United States; ²Department of Cogno-Mechatronics Engineering, Pusan National University, Pusan, Republic of Korea

In a combined MRI and SPECT system (MR-SPECT), metallic components of the SPECT hardware distort the B₀ field for MR imaging. Rotation of the SPECT hardware for tomographic imaging thus alters the B₀ field and requires re-shimming. To perform rapid re-shimming, pre-determined field maps were utilized to calculate the optimum currents to apply to the shim channels. These calculations do not require any additional MRI acquisitions, allowing for re-shimming immediately after any rotation.