Developing a novel phantom for image quality evaluation in digital radiography

Abstract

Evaluation of image quality in digital radiography is important to ensure accurate diagnosis. However, to perform image quality tests accurately and effectively, complex techniques and numerous phantoms are required. The aim of the study was to develop a novel phantom to allow a comprehensive evaluation of image quality in digital radiography. High-Density Polyethylene (HDPE) was used as the main material for the phantom. Physical image quality parameters such as effective Modulation Transfer Function (eMTF), effective Normalized Noise Power Spectra (eNNPS), effective Detective Quantum Efficiency (eDQE), as well as contrast and signal-to-noise ratio (SNR) evaluations can be conducted using the phantom. Preliminary preparation work was carried out through Monte Carlo simulations. The validation of the phantom was performed by comparing with standard phantom results. Physical image quality measurements were performed using an indirect digital radiography system. It was observed that there was a good agreement between the image quality measurement results performed with the standard phantom and the developed phantom. A strong correlation was determined between integrated effective DQE (IeDQE) results (R ≥ 0.97) obtained with HDPE and PMMA phantom. Simulation results regarding the transmission factor showed that HDPE could be an alternative to Polymethyl Methacrylate (PMMA) as a phantom material.