1. A method for constructing an image from an MRI data set, comprising: employing a spiral trajectory to acquire the MRI data set; determining for respective pixels in an image being constructed, a frequency parameter representative of a measure of off-resonance signal for voxels associated with the respective pixel; processing as a function of the frequency parameter, the MRI data set to generate a first image and a second image; and deblurring at least one of said first and second images as a function of the frequency parameter.