THREE DIMENSIONAL BACK PROJECTION METHOD INCLUDING STEPS OF DETERMINING PLANE PROJECTION DATA, AND DETERMINING BACK PROJECTION PIXEL DATA, AND X-RAY CT APPARATUS

摘要

PURPOSE: A three dimensional back projection method and an X-ray CT apparatus are provided to allow for a cone beam reconstruction by using projection data accurately corresponding to X-ray beam passing through a reconstruction region. CONSTITUTION: A three dimensional back projection method comprises a step of determining plane projection data(D1) by projecting projection data(D0) collected by at least one of an axial scan and a helical scan through the use of a multi-detector(24) on a projection plane, wherein the multi-detector includes a plurality of detector arrays; a step of determining back projection pixel data(D2) by projecting data(D1) on a reconstruction region in an X-ray transmitting direction, wherein the reconstruction region includes a plurality of pixels; and a step of determining back projection pixel data(D3) by summing back projection pixel data(D2) for each corresponding pixel of all views used in image reconstruction.