Real-time cone-beam CT image reconstruction using a mercury’s dual cell-based system (DCBS) and a Sony’s Playstation 3 (PS3) cluster

摘要

Based on our previous work on hyperfast back-projection on cell broadband engine (CBE) systems, we developed a complete Feldkamp reconstruction scheme for flat panel detector CT scanners. The scheme comprises preprocessing of the rawdata, convolution, perspective backprojection and data IO. As reconstruction hardware we use a DCBS and alternatively a cluster of four PS3 computers. Both allow us to process up to 30 projections per second of size 5122 pixels and backproject them into a volume of 5123 voxels with 32-bit floating-point accuracy. However, due to its strongly limited amount of memory the PS3 cluster is not suited for bigger volumes or iterative reconstruction schemes. For such sophisticated tasks a professionel hardware like the DCBS is essential. The whole reconstruction runs completely during the acquisition time of the CT scanner, hence the reconstructed volume is available immediately after the scan. In this sense, we call it realtime. We validated this real-time capability by connecting the CBE systems into the reconstruction pipeline of our micro-CT scanner TomoScope 30s Duo.