Determination of weighting functions for energy-weighted acquisition.

Energy-weighted acquisition (EWA) is an image filtering technique, with a different spatial filter (weighting function) for each energy. The imaging characteristics of EWA are governed by the weighting functions used during the acquisition of the image. The determination of weighting functions is more complicated than the determination of energy windows in conventional imaging because the number of degrees of freedom is much greater.

Energy-weighted acquisition of scintigraphic images using finite spatial filters.

Energy weighted acquisition (EWA) is a technique for improving image contrast by correcting for some of the blurring effects of Compton scattering within the patient. We outline image formation theory as it applies to energy weighting and present a pre-processing implementation that acquires images with real-number energy-dependent weighting functions of finite spatial extent. The effect of scattered radiation on quantitative accuracy, with and without EWA, is demonstrated with sheet and point sources at various depths.