New method for the experimental evaluation of x-ray grids

This work describes a new method for the experimental evaluation of antiscatter x-ray grids in radiography. Five commercial grids are evaluated in terms of two parameters which are determined only by the construction of the grid and the x-ray energy. A comparison of the grid performances was made for the x-ray energies and scatter conditions that usually apply to chest radiography and mammography. The results show that for maximum scatter conditions the grid enhances the subject contrast by factors of approximately 6 and 2 in chest radiography and mammography, respectively, and that the contrast increases as the grid ratio increases. Also, in these examinations, the results show that, with improved grids, it is possible to reduce the patient exposures required for the no-grid case by approximately one-half without loss of the image-information content (signal-to-noise ratio).