EVALUATION OF RESPIRATORY ARTIFACT CORRECTION TECHNIQUES IN MULTISHOTSPIRAL FUNCTIONAL MRI USING RECEIVER OPERATOR CHARACTERISTIC ANALYSES

Navigator corrections and low-spatial frequency (LSF) over-sampling ar e investigated as methods for reducing respiration-related effects in multishot functional MRI. Both techniques take advantage of the smooth ly varying or nearly constant phase variations linked to the respirati on cycle. These techniques were tested in functional MRI studies with spiral k-space acquisitions. Receiver operator characteristic (ROC) an alyses and the temporal variance averaged across the brain were used t o evaluate their effectiveness. Both methods were found to increase th e area under the ROC curve and to reduce the standard deviation, with the LSF oversampling method being more effective.