1. A method for correcting attenuation of positron emission tomography (PET) image data of an area under examination, comprising: a. segmenting magnetic resonance (MR) images of the area under examination utilizing a patch-based segmentation technique; b. creating pseudo-computed tomography (CT) images from the segmented MR images; and c. generating attenuation correction maps for the PET image data from the pseudo-CT images.