title: Sinogram-based super-resolution in PET.
abstract: Spatial resolution is intrinsically limited in positron emission tomography (PET) systems, mainly due to the crystal width. To increase the spatial resolution for a given crystal width, mechanical movements such as wobble and dichotomic motions are introduced to the PET systems. However, multiple sinograms obtained through such movements provide oversampled data. In this paper, to increase the spatial resolution, we present a novel super-resolution (SR) scheme that employs multiple sinograms. For SR, we first propose a blur kernel estimation scheme through a Monte Carlo simulation. Based on the estimated blur kernel, we adopt a maximum a posteriori expectation maximization method in estimating a high-resolution sinogram from multiple low-resolution sinograms. The proposed algorithm provides noticeable improvement of the spatial resolution in real PET images.
authors.affiliation: Department of Electrical Engineering, KAIST, Korea.
authors.forename: Kye Young
authors.initials: KY
authors.lastname: Jeong
authors.forename: Kyuha
authors.initials: K
authors.lastname: Choi
authors.forename: Woo Hyun
authors.initials: WH
authors.lastname: Nam
authors.forename: Jong Beom
authors.initials: JB
authors.lastname: Ra
mesh_terms: D007089:Image Enhancement / Q000379:methods*; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography / Q000379:methods*