  Images from positron emission tomography (PET) provide metabolic information
about the human body. They present, however, a spatial resolution that is
limited by physical and instrumental factors often modeled by a blurring
function. Since this function is typically unknown, blind deconvolution (BD)
techniques are needed in order to produce a useful restored PET image. In this
work, we propose a general BD technique that restores a low resolution blurry
image using information from data acquired with a high resolution modality
(e.g., CT-based delineation of regions with uniform activity in PET images).
The proposed BD method is validated on synthetic and actual phantoms.
