Development of a quality control program for a cone beam CT imaging system

Abstract

Routine quality control assessments of medical equipment are crucial for an accurate patient medical treatment as well as for the safety of the patient and staff involved. These regular evaluations become especially important when dealing with radiation-emitting equipment. Therefore, a quality control (QC) program has been developed to quantitatively evaluate imaging systems by measuring standard parameters related to image quality such as the Modulation Transfer Function (MTF), the Noise Power Spectrum (NPS), uniformity, linearity and noise level among others. First, the methods of evaluating the aforementioned parameters have been investigated using a cone beam CT imaging system. Different exposure techniques, phantoms, acquisition modes of the flat panel detector (FPD) and reconstruction algorithms relevant to a clinical environment were all included in this investigation. Second, using the results of the first part of this study, a set of parameters for the QC program was established that yields both, an accurate depiction of the system image quality and an integrated program for easy and practical implementation. Lastly, this QC program will be implemented and practiced in our cone beam CT imaging system. The results using our available phantoms demonstrate that the QC program is adequate to evaluate stability and image quality of this system since it provides comparable parameters to other QC programs.