A measuring tool devoted to improve the evaluation of image parameters for quality assurance/quality control programs of CT scanners

Computed Tomography (CT) is one of the most widely used screening and diagnostic tools in medical imaging centers. Considering IAEA HUMAN HEALTH SERIES No. 19 and the American College of Radiology (ACR) Accreditation Program, quality assurance (QA) and quality control (QC) are mandatory programs to periodically monitor the system condition to promote the effective utilization of ionization radiation for a diagnostic outcome through obtaining and retaining appropriate image quality and reduction of patient dose. Computational phantoms (CPs) are the key tool to monitor system condition. The commercial QC phantoms are expensive products and are not flexible enough for user demands. Also, it has recently been reported that standard parameters based on IAEA and ACR, including noise magnitude, and resolution, are not accurate parameters for quantitatively evaluating system performance in terms of image quality. In this paper, we designed and fabricated a new CP along with a graphical user-friendly interface program integrally called “QCT” enabling to measure IAEA/ACR-based standard image parameters and beyond metrics including CT calibration curve, CT number of multiple objects, contrast-to-noise ratio, the edge spread function, the line spread function, the modulation transfer function, spatial resolution, noise power spectrum, image noise, and uniformity. The experimental assessment of QCT was tested on a GE LightSpeed VCT multi-detector CT scanner available in Emam-Khomeini hospital complex. In addition, we reported the details of fabrication process of our QC phantom, enabling readers to create flexible and affordable QC phantoms.