Neuroimaging Applications of Photon-counting CT

Photon-counting computed tomography (PCCT) is a new imaging technology that has advanced diagnostic imaging by offering improved spatial and contrast resolution as well as novel spectral imaging capabilities. Unlike conventional CT, which uses energy-integrating detectors, PCCT employs photon-counting detectors that directly measure individual photon energies, enabling applications such as virtual monochromatic imaging (VMI) and material decomposition. These innovations allow for artifact reduction, better visualization of fine anatomic structures, and improved diagnostic accuracy, all while reducing radiation dose. This review explores select applications of PCCT in neuroimaging, focusing on the brain, temporal bone, and spine. In the brain, we discuss how PCCT demonstrates superior performance for evaluating aneurysms, metallic prostheses, and vessel stenosis, offering enhanced visualization of vascular structures and minimizing artifacts. For temporal bone imaging, we review assessment of both complex anatomy and potentially subtle pathologies such as otosclerosis, as well as visualization of implants like cochlear devices and their intricate components. In spinal imaging, we explore how PCCT improves precise detection of causes of cerebrospinal fluid leaks, improves localization of tiny vessels such as the artery of Adamkiewicz and spinal dural arteriovenous fistulas, and reduces metal artifacts associated with postoperative hardware. PCCT addresses limitations of conventional CT while unlocking new diagnostic possibilities across neuroimaging applications. As clinical adoption of PCCT grows, ongoing research and development will refine imaging protocols and expand its utility. The accumulating evidence underscores PCCT's transformative potential to improve diagnostic confidence in neuroimaging and beyond.