18–22 Feb 2019
Vienna University of Technology
Europe/Vienna timezone

Evaluation of a novel photon-counting CT system using a 16-channel MPPC array for multicolor 3-D imaging

21 Feb 2019, 14:00
20m
EI8

EI8

Talk Medical Applications Medical Applications

Speaker

Mr Takuya Maruhashi (Waseda University)

Description

X-ray computed tomography (CT) is widely used in diagnostic imaging of the interior of the human body; however, the radiation dose of conventional CT typically amounts to 10 mSv. Under such environments, X-ray photons are severely piled-up; therefore, the CT images are monochromatic and various artifacts are present due to beam hardening effects. In contrast, photon counting CT (PC-CT) offers a low dose and multicolor CT system. At present, PC-CT systems based on CdZnTe devices are widely studied. This system is yet far from being an established clinical technique, owing to the high-cost and complexity of huge number of read out channels; the pixel size of CdZnTe must be as small as ~0.1-0.2 mm to withstand high counting rate due to the slow mobility of electron-hole pairs. In this paper, we propose a cost-effective, novel PC-CT system consisting of 16-ch multipixel photon counter (MPPC) coupled with a high-speed scintillator array. As a proof of concept, we show 3-D color images of a lighter phantom taken in a sufficiently low-dose environment. Material identification is possible by setting multiple energy windows. Next, we applied our PC-CT system for K-edge imaging, which can improve blood-tissue contrast using a specific contrast agent. By setting appropriate energy windows, our PC-CT system accurately reconstructed absolute concentration of iodine and gadolinium. Finally, we discuss the prospects and possible future clinical applications of the developed PC-CT system.

Primary author

Mr Takuya Maruhashi (Waseda University)

Co-authors

Prof. Makoto Arimoto (Kanazawa University) Prof. Jun Kataoka (Waseda University) Mr Hiroaki Kiji (Waseda University) Mr Shinsuke Terazawa (Hitachi Metals Ltd) Mr Hideo Nitta (Hitachi Metals Ltd) Mr Satoshi Shiota (Hitachi Metals Ltd) Prof. Hirokazu Ikeda (Institute of Space and Astronautical Science)

Presentation materials