| Title | Image correction during large and rapid B(0) variations in an open MRI system with permanent magnets using navigator echoes and phase compensation. |
| Publication Type | Journal Article |
| Year of Publication | 2009 |
| Authors | Li J, Wang Y, Jiang Y, Xie H, Li G |
| Journal | Magn Reson Imaging |
| Volume | 27 |
| Issue | 7 |
| Pagination | 988-93 |
| Date Published | 2009 Sep |
| ISSN | 1873-5894 |
| Keywords | Adult, Algorithms, Artifacts, Brain, Female, Humans, Image Enhancement, Image Interpretation, Computer-Assisted, Magnetic Resonance Imaging, Male, Phantoms, Imaging, Reproducibility of Results, Sensitivity and Specificity |
| Abstract | An open permanent magnet system with vertical B(0) field and without self-shielding can be quite susceptible to perturbations from external magnetic sources. B(0) variation in such a system located close to a subway station was measured to be greater than 0.7 microT by both MRI and a fluxgate magnetometer. This B(0) variation caused image artifacts. A navigator echo approach that monitored and compensated the view-to-view variation in magnetic resonance signal phase was developed to correct for image artifacts. Human brain imaging experiments using a multislice gradient-echo sequence demonstrated that the ghosting and blurring artifacts associated with B(0) variations were effectively removed using the navigator method. |
| DOI | 10.1016/j.mri.2009.01.022 |
| Alternate Journal | Magn Reson Imaging |
| PubMed ID | 19369023 |
Related Institute:
MRI Research Institute (MRIRI)