Analysis of digital radiographic equipments with development of specific phantoms and software

Abstract

In this work we have designed some specific phantoms to study the obtained image of computerized and direct digital radiographic equipments to characterize the constancy of the imaging chain. The developed phantoms are applied for different radiographic digital devices, as conventional equipments with computed radiography (phosphor plate) and direct radiography (sensor) technology. These phantoms have specific characteristics for these systems, as different test zones for the analysis of the image quality. The test zones that are in these phantoms are low contrast objects, varying in diameter and size, for the threshold contrast resolution of the system, high resolution test for the limiting spatial resolution, dynamic step wedge for the dynamic range of grays of the system, homogeneity zone and alignment marks for position and size of radiation field. Additionally, we have developed a software based on automatical processing techniques to analyze the image obtained by the radiographic equipment with digital processing techniques as edge detector, morphological operators, statistical test for the detected combinations. The images have been acquired in DICOM format and they can be analyzed with objective parameters as an image quality index and the contrast detail curve. The design of these phantoms let the evaluation of a wide range of operating conditions of voltage, current and time of the digital radiographic equipments and the functioning of the image chain of the digital system applied to its quality control for image quality and radiation exposure.Keywordsphantomimage processingquality controldigital radiography