Determining when 3D reconstruction methods are required in volume PET imaging

An attempt is made to determine at which point a 3-D reconstruction algorithm is needed for a volume imaging scanner as the axial extent is increased. From simulations of an existing volume PET (positron emission tomography) scanner with a maximum axial acceptance angle (φ) of 9 deg, it is shown that a two-dimensional image reconstruction with α=9 deg is a compromise between sensitivity, speed, and accuracy compared to a two-dimensional reconstruction with a software limit of α=1 deg and a three-dimensional reconstruction with α=9 deg. It is also shown that a proposed scanner with α=27 deg requires three-dimensional reconstruction in order to achieve maximum sensitivity without unacceptable losses in accuracy