title: Split-filter computed tomography: a simple technique for dual energy scanning.
abstract: A simple technique for obtaining dual energy information from a single computed tomography (CT) scan is described. The method involves filtering the two halves of the X-ray fan beam differently. It is shown that during a 360 degree scan, this split-filtration geometry results in dual energy noise analysis, valid for polychromatic X-ray beams, is presented and used to determine the optimal parameters for the split-filter scans. Using the theoretically optimal split-filter design installed on a commercial CT scanner, photoelectric and Compton images of a head phantom were obtained. Recombination of the photoelectric and Compton components of attenuation at arbitrary energies demonstrates the ability to remove spectral artifacts from conventional CT images.
mesh_terms: D002138:Calibration; D005374:Filtration / Q000295:instrumentation; D008962:Models, Theoretical; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014965:X-Rays