A pulse sequence eliminating zipper artifact of MRI / 中国组织工程研究

ABSTRACT

BACKGROUND: Various artifacts are found to be appeared in the nuclear magnetic resonance; the frequently appearing ones are the motion artifacts, plait artifacts, metallic artifacts, partial volume effect artifacts, chemical shift artifacts, phase artifacts, zipper artifacts and so on. However, there is still has no report on the controlling and revising method of the zipper artifacts which is produced in the spin-echo sequence imaging process. OBJECTIVE: Based on the discussion of the mechanism of the production of zipper artifact in the spin-echo sequence imaging process, a new impulse sequence is worked out to avoid the zipper artifact. METHODS: Standard SE sequence was complied to obtain the standard image, and compiling the artifact sequence to obtain the linear disturbance image and zipper artifact image, compiling the modified sequence to obtain the modified zipper artifact image. RESULTS AND CONCLUSION: Usually, the linear disturbance image could obtained in the instantaneous gradient of 5 degree with the echo sequence of 120 degree, and the zipper artifact will be obtained in the instantaneous gradient of 90 degree with the echo sequence of 120 degree. Modified sequence instantaneous gradient of 90 degree with the echo sequence of 120 degree can completely eliminate zipper artifact. The interesting result obtained in this paper is that the zipper artifact can be totally avoided with this new impulse sequence.