Real time data averager for use in computed tomography scanning

Abstract

A helical CT scanning system includes a real time averager that rapidly processes data from the system's detector array, to enable substantially real time production of X-ray images. The averager, which may be used with an scanning electron beam CT system operating in conventional or helical mode, or with a rotating mechanical gantry CT scanner operated in conventional or helical mode, includes an adder and first and second memory banks and an input FIFO register. The FIFO register synchronously communicates system detector array data to the adder. The adder combines this input data with data previously stored in one of the memory banks. For example, after a first X-ray scan, detector data are written via the FIFO and adder into the first data bank, and after a subsequent scan, the sum of the original data in the first data bank is added to the new data corresponding to the second scan, and the new summation is written into the second data bank. After a third scan, new data corresponding to the third scan is added to the data in the second data bank and the new summation is written into the first data bank, and so on. The data in the most recently acquired data bank is divided by the number of scans per resultant image (N) to provide a running real time or 'on the fly' average value of data per scan.