Small Fov Imaging Using Wavelet Encoding with 2 Dimensional Rf Pulses and Gradient Echo

Introduction: Several magnetic resonance imaging (MRI) applications, such as cardiac imaging and functional MRI, require the use of small Field of View (FOV) imaging to achieve dynamic MR studies. However, using small FOV with Fourier encoding results in aliased images in the phase encoding direction. Several approaches have been used to solve the aliasing problem. Among the proposed techniques, wavelet encoding appears to be a promising alternative, since it localizes regions of interest, which allows for FOV size reduction without folding. Most of the MRI wavelet encoding (WE) sequences uses spin-echo sequence for imaging, which is time consuming. In this work we propose the use of a modified gradient-echo sequence where phase encoding is replaced by wavelet encoding using RF pulses; which play the role of the wavelet functions in wavelet encoding process . Two dimensional RF pulses are used to achieve simultaneously slice selection and wavelet encoding in the echo-planar k-space RF pulse trajectory.