Contrast-Medium-Enhanced Digital Mammography: Comparison of Standard vs. High-Energy Spectra for Dual-Energy Temporal Subtraction

摘要

This work aims at comparing, experimentally, the image quality performance of two alternative dual-energy spectral combinations for the clinical application of contrast-medium-enhanced digital mammography (CEDM). The first option uses standard X-ray spectra and the second, relatively energetic hardened beams, all selected from a previous analytical optimization. Phantom and clinical exposures use a GE Senographe DS unit. The clinical protocol includes obtaining 2 mask images (without contrast medium) followed by administration of an iodine-based contrast medium and a series of 3 post-injection images, all under soft breast compression. Results from the phantom study -which agree with numerical predictions- show that, for iodine concentrations less than about 4.5 mg cm~(-3) in the structure of interest and under dose constraints, standard spectra offer contrast-to-noise ratios higher than the second spectral option. Initial clinical results of the procedure with standard spectra have been obtained. Two lesions are visually enhanced in the subtracted images of five patients with suspicious lesions, confirmed as malignant by biopsy after the application of CEDM. Based on these results, the technique and the image processing algorithm are currently under optimization.