Dual-energy imaging of the chest: optimization of image acquisition techniques for the 'bone-only' image

Med Phys. 2008 Feb;35(2):629-32. doi: 10.1118/1.2828186.

Abstract

Experiments were conducted to determine optimal acquisition techniques for bone image decompositions for a prototype dual-energy (DE) imaging system. Technique parameters included kVp pair (denoted [kVp(L)/kVp(H)]) and dose allocation (the proportion of dose in low- and high-energy projections), each optimized to provide maximum signal difference-to-noise ratio in DE images. Experiments involved a chest phantom representing an average patient size and containing simulated ribs and lung nodules. Low- and high-energy kVp were varied from 60-90 and 120-150 kVp, respectively. The optimal kVp pair was determined to be [60/130] kVp, with image quality showing a strong dependence on low-kVp selection. Optimal dose allocation was approximately 0.5-i.e., an equal dose imparted by the low- and high-energy projections. The results complement earlier studies of optimal DE soft-tissue image acquisition, with differences attributed to the specific imaging task. Together, the results help to guide the development and implementation of high-performance DE imaging systems, with applications including lung nodule detection and diagnosis, pneumothorax identification, and musculoskeletal imaging (e.g., discrimination of rib fractures from metastasis).

Publication types

  • Evaluation Study

MeSH terms

  • Algorithms*
  • Bone and Bones / diagnostic imaging*
  • Humans
  • Radiographic Image Enhancement / methods*
  • Radiographic Image Interpretation, Computer-Assisted / methods*
  • Radiography, Dual-Energy Scanned Projection / methods*
  • Radiography, Thoracic / methods*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Subtraction Technique*