Reduced and weighted field-of-view imaging using spatially-selective excitation in MRI: A simulation study

Abstract

This study demonstrated spatially-selective excitation for reduced and weighted field of view (FOV) imaging. Two-dimensional spatially-selective radiofrequency (2D SSRF) excitation can be achieved by using a spatially-selected combination of gradients for two independent axes and the corresponding radiofrequency pulse. Different corresponding excitation profiles can be derived from pulse sequence parameters such as the number of sub-pulses, the pulse duration and the phase encoding gradient waveforms. In the 2D SSRF pulse, the corresponding excitation profile becomes wider when the phase encoding gradient area is decreased. Moreover, the edge region is reduced and central region weighted spatial profiles can be obtained by using a 1-1 binomial spatiallyselective excitation. This characteristic of a 1-1 binomial spatially-selective excitation among the various types of 2D SSRF pulses allows shorter pulse duration and does not increase the scan time. Furthermore, the spatial weighting property using a 1-1 binomial spatially-selective excitation can be exploited to significantly under-sample k-space for sensitivity encoding reconstruction.