Poster — Wed Eve—12: Initial Experiments in Monoenergetic X‐Ray Scatter Imaging at the BioMedical Imaging and Therapy facility of the Canadian Light Source

• Published in: Medical Physics Vol. 36; no. 9; p. 4306
• Main Authors: Johns, PC, Bewer, BE, Chapman, LD
• Format: Conference Proceeding Journal Article
• Language: English
• Published: American Association of Physicists in Medicine 01-09-2009
• Subjects: Light scattering; Medical image contrast; Medical imaging; Particle beam detectors; Photon scattering; Photons; Synchrotron radiation; X‐ray detectors; X‐ray scattering; X‐rays
• ISSN: 0094-2405; 2473-4209
• DOI: 10.1118/1.3244116

In projection x‐ray imaging, in the absence of a grid scattered x‐ray photons from the patient out‐number primary photons at the image receptor by as much as 10:1. Scattered radiation can significantly degrade projection contrast and signal‐to‐noise ratio in conventional projection imaging, but can also be used as a source of additional information about the patient or object examined. In principle, a raster scan by a primary pencil beam and two‐dimensional scatter field detector could be used to acquire the scatter information. Simultaneous measurements would reduce acquisition time. Here we report on our first investigations of using a fan beam. We used a monoenergetic radiation beam at the BioMedical Imaging and Therapy (BMIT) facility at the Canadian Light Source (CLS) synchrotron (Saskatoon, Saskatchewan). X rays of approximately 40 keV produced by the 05B1–1 bend magnet beamline were used with Computed Radiography plates as the detector. The fan beam was 1.1 mm thick by 10.6 cm wide. The circularly‐symmetric diffraction patterns of water, plastics, and porcine tissue samples were sampled outside of the fan plane. Signal processing based on cross‐correlation of the scatter field with arc patterns was investigated as a means to provide approximate localization of materials in the fan plane. A more sophisticated signal‐processing approach and/or collimation strategy will likely be necessary.