Two major x‐ray‐based techniques used for medical imaging are digital radiography (DR) and computed tomography (CT). Most of their detectors integrate the intensity of x‐ray flux and output gray scale images or projections. Detectors with indirect detection type heavily weigh x‐ray photons with higher energy as they generate more lights. This results in suboptimal contrast of images because the contrast of different tissues reduces in general as the energy of photons increases. In the past few years, there have been strong reviving research interests in an old concept—the use of the photon energy—to improve the quality and accuracy of diagnosis. Recently, novel photon counting x‐ray detectors (PCXDs) with energy discrimination capabilities have been developed for x‐ray DR and CT imaging. These PCXDs counts the number of x‐ray photons within multiple energy windows. This allows us to improve the quality of the current gray scale images and the accuracy of the material decomposition. We will discuss the state‐of‐the‐art detector technologies and imaging methods unique to these PCXDs.
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging