3524
A Method for Correcting Non-linear Errors in Radial Trajectories
Hideaki Kutsuna1, Sho Kawajiri2, and Hidenori Takeshima3
1MRI Systems Development Department, Canon Medical Systems Corporation, Kanagawa, Japan, 2MRI Systems Development Department, Canon Medical Systems Corporation, Tochigi, Japan, 3Advanced Technology Research Department, Research and Development Center, Canon Medical Systems Corporation, Kanagawa, Japan
The authors propose a new method to use a non-linear model for correcting errors in radial trajectories. The proposed method suppresses streak artifacts and image shadings which appear with conventional linear correction.

Illustration of the estimation procedure for the trajectory shifts.

Blue arrows represent the first blade.

Red arrows represent the second blade.

Reconstructed images obtained from the stack-of-stars volunteer scan, under free-breathing

(a) Image reconstructed without correction

(b) Image reconstructed with the linear correction

(c) Image reconstructed with the non-linear correction.

Comparing (b) to (c), streak artifacts (arrow 1) and image shading (arrow 2) are suppressed in (c).

The scan parameters: TE=1.3ms, TR=3.6ms, FOV=35cm*35cm, matrix-size=256*256, sampling-pitch=6$$$\mu$$$s, number-of-slices=50, slice-thickness=4mm, number-of-trajectories=800.