SENSE reconstruction with inaccurate sensitivity functions: effects and remedies

Image reconstruction in parallel imaging using an array of phased receiver coils involves solving a matrix equation whose coefficient matrix is formed from estimated coil sensitivity functions. Inaccurate sensitivity functions can create image artifacts and reduce signal-to-noise ratio (SNR). This paper discusses the effects of inaccurate sensitivity functions and proposes some remedies to reduce these effects. Specifically, a spatially varying wavelet denoising method is proposed to improve the accuracy of the estimated sensitivity maps, and a constrained reconstruction method is used to incorporate a priori information about the location of the regions of interest to further improve the SENSE reconstruction.