Increasing Sparsity in Compressed Sensing MRI by Exponent of Wavelet Coefficients

YUDONG ZHANG¹, ², BRADLEY PETERSON¹, ², ZHENGCHAO DONG¹, ²

Compressed sensing was introduced to the field of magnetic resonance imaging in recent years as a promising method to significantly reduce scan time. The performance of CS depends on the sparsity of the image in the sparse domain, such as wavelet transform domain. In this report, we proposed a method to increase the sparsity of CS MRI by taking exponent of wavelet transform normalized to the range [0 1]. The method was tested on a digital phantom and in vivo MRI data, and the results show that EXP-WT can improve the quality of the reconstructed image or significantly speed up the reconstruction.