Principles and Clinical applications of Photon-Counting Detector Computed Tomography (PCD CT) -A Comprehensive Review

Abstract

Photon-counting computed tomography (PCCT) represents a significant advancement in CT imaging technology. Unlike conventional energy-integrating detectors (EIDs), PCCT employs photon-counting detectors (PCDs) that directly convert X-ray photons into electrical signals. This enables enhanced spatial resolution, reduced electronic noise, and improved dose efficiency. The ability to perform multi-energy acquisition and material decomposition further extends PCCT’s clinical applications. This review explores the evolution of CT detector technology, the principles of PCCT, its advantages over conventional CT, and its diverse clinical applications—including cardiovascular imaging, oncology, musculoskeletal imaging, and pediatric imaging. We also discuss the challenges, limitations, and future perspectives of PCCT in clinical radiology