Dual-Energy Low-Scattering X-Ray Computed Tomography Using a Lutetium-Oxyorthosilicate Crystal and a Small Photomultiplier Tube

Yasuyuki Oda, Mikihisa Kamada, Yoshikuni Ishihama, Risako Miwa, Nanase Terashima, Koichiro Sato, Kohei Ando, Eiichi Sato

Abstract: To perform low-dose low-scattering X-ray computed tomography (CT), we have constructed a dual-energy (DE) X-ray photon counter with a high-count-rate detector system and energy-range and -region selectors. The detector system consists of a lutetium-oxyorthosilicate (LSO) crystal, a small photomultiplier tube (sPMT), and a simple inverse amplifier for LSO-sPMT with a pulse-width extender. In DE-CT, both the X-ray source and the detector module are fixed, and the object on the turntable oscillates on the translation stage. Line beams for DE-CT are formed using a lead pinhole and a front tantalum (Ta) x-y slit placed just in front of the object. The scattering-photon count from the object is reduced using a back Ta slit. X-ray photons are detected using the detector system, and the event pulses are input to the two energy selectors. In DE-CT, the tube voltage and current were 60 kV and 1.0 mA, respectively. The energy range and region for soft and iodine-K-edge CT are 12-31 and beyond 35 (35-60) keV, respectively. The maximum count rate of DE-CT was 75 kilocounts per second, and the exposure time for tomography was 19.6 min at a total rotation angle of 360. Outlines of the objects were clearly visible by reducing scattering-photon counts.

Keywords: LSO-sPMT Detector, X-Ray CT, Dual-Energy Dispersion, Low-Dose CT, Low-Scattering Count, I-K-Edge CT

How to Cite?: Yasuyuki Oda, Mikihisa Kamada, Yoshikuni Ishihama, Risako Miwa, Nanase Terashima, Koichiro Sato, Kohei Ando, Eiichi Sato, "Dual-Energy Low-Scattering X-Ray Computed Tomography Using a Lutetium-Oxyorthosilicate Crystal and a Small Photomultiplier Tube", Volume 7 Issue 6, June 2018, International Journal of Science and Research (IJSR), Pages: 1584-1589, https://www.ijsr.net/getabstract.php?paperid=ART20183510, DOI: https://dx.doi.org/10.21275/ART20183510