Abstract-In discrete detector PET, natural pixels are image basis functions calculated from responses of detector pairs. By using reconstruction with natural pixels the discretization of the object into a predefined grid can be avoided. Instead of trying to find the object from system matrix and measured data by solving , one solves !#"$% . The backprojection of the final results in the estimated image of the object & . In previous work natural pixels were calculated by intersections of strip functions or combinations of strip functions. However, in PET systems the detector response is not correctly described by a strip function. In PET the detector response is better described by a gaussian tube. It is quite difficult to calculate the intersections of all possible Lines Of Response (LOR) in the scanner. This paper proposes an easy and efficient way to generate the matrix directly by Monte Carlo simulation. Using the natural pixel matrix has several advantages over usin...
Charles L. Byrne, Stefaan Vandenberghe, Edward J.