Limitations to accuracy in dual energy digital fluoroscopy

A digital fluoroscopy system has many desirable features for energy selective imaging. Unfortunately it has significant problems which may prevent it from being used for this application. Two techniques for overcoming the limitations of digital fluoroscopy are presented. The first attacks the lack of absolute measurements in data from digital fluoroscopy. The nonlinear processing used in energy selective imaging requires absolute data. Techniques are presented which use relative measurements and still allow selective material imaging. Digital fluoroscopy is normally used for subtraction imaging so that errors in the data tend to cancel. By using a generalization of subtraction imaging called hybrid subtraction, the errors introduced by using fluoroscopic data in energy selective imaging can be significantly reduced.