Implementation of the Weighted L1-Norm Scatter Correction Scheme in Dual-Energy Radiography

Abstract

Dual-energy radiography (DER) based on basis material decomposition (BMD) is a wellestablished X-ray technique that uses low- and high-kV radiographs to separate soft and dense tissues. Conventional DER methods often lead to reduced image contrast in resulting dual-energy images when extensive X-ray scatter is present in the images. In this study, we applied the weighted l¹-norm scatter correction algorithm in conventional DER to create a scatter correction scheme able to overcome the reduced image contrast associated with dual-energy images. The proposed DER process consists of two main steps: (1) the generation of a scatter-corrected pairwise lookup table for equivalent acryl and aluminum thicknesses and (2) the separation of soft and dense tissues based on BMD. We performed a computational simulation and an experiment to investigate the image quality and evaluate the effectiveness of the proposed DER method. Polychromatic X-ray images were emulated at two different tube voltage settings (80 kV_p and 140 kV_p); then, the images were corrected for scatter prior to BMD. Our results indicate that the proposed scatter correction algorithm implemented in conventional DER effectively reduces X-ray scatter in radiography and results in improved DER image quality.