X-ray differential phase contrast and dark-field computed tomography and radiography with microbubbles as contrast agent

Motivated to improve the low contrast detectability of x-ray imaging in soft tissues, increasing effort has been devoted to the research and development of refraction-based x-ray phase contrast imaging. Among all existing implementations, the x-ray tube and grating based differential phase contrast imaging is of high potential to become an imaging modality for preclinical and eventually clinical applications. Based on our preliminary investigation and recognizing the clinical success of iodine contrast agent in conventional attenuation-based x-ray imaging, we propose the grating-based x-ray differential phase contrast and dark-field imaging method with microbubbles as the contrast agent. Via computer simulation, we investigate the feasibility of the proposed x-ray differential phase contrast and dark-field computed tomography in this work. Preliminary data show that at the detector cell dimension adequate for both clinical (>100μm) and preclinical (≤100μm) applications, the contrast between microbubbles and soft tissues in x-ray differential phase contrast and dark-field computed tomography images is substantially larger than its counterpart in the conventional attenuation-based CT, which encourages further in-depth investigation along this scientific and technological avenue.