ANALYTICAL RECONSTRUCTION FORMULA FOR ONE-DIMENSIONAL COMPTON CAMERA

The Compton camera has been proposed as an alternative to the Anger ca mera in SPECT. The advantage of the Compton camera is its high geometr ic efficiency due to electronic collimation. The Compton camera collec ts projections that are integrals over cone surfaces. Although some pr ogress has been made toward image reconstruction from cone projections , at present no filtered backprojection algorithm exists. This paper i nvestigates a simple 2D version of the imaging problem. An analytical formula is developed for 2D reconstruction from data acquired by a 1D Compton camera that consists of two linear detectors, one behind the o ther. Coincidence photon detection allows the localization of the 2D s ource distribution to two lines in the shape of a ''V'' with the verte x on the front detector. A set of ''V'' projection data can be divided into subsets whose elements can be viewed as line-integrals of the or iginal image added with its mirrored shear transformation. If the dete ctor has infinite extent, reconstruction of the original image is poss ible using data from only one such subset. Computer simulations were p erformed to verify the newly developed algorithm.