Navigators Improve Accuracy of Quantitative Sodium MR Imaging Compromised by Head Motion During with Long Acquisition Times

Aiming Lu¹, Ian C. Atkinson¹, Keith R. Thulborn¹

Quantitative sodium MR imaging with flexible twisted projection imaging (flexTPI) provides valuable information about regional changes in tissue sodium concentration (TSC) in human brain tumors responsive to fractionated radiation treatment. The acquisition time of 10 minutes is at the upper limits for which a patient can be expected to remain stationary. Stimulations show that quantification of TSC is compromised by even small head motions without appreciable degradation of the visual impression of image quality. Navigators incorporated within the flexTPI sequence have been investigated as a means of detecting head motion during acquisition and then correcting the quantification of TSC.