Pictorial review: a step-by-step guide to coronary CT angiography with photon-counting detector CT

Recent advances in CT technology have led to the advent of the photon-counting detector CT (PCD-CT). The technology has shown significant improvements in CT image quality with high spatial resolution, more accurate differentiation of coronary plaque components, and radiation reductions compared to the energy-integrating detector-CT (EID-CT). However, limited experience exists, and little has been published on the decision-making process for PCD-CT coronary scanning protocols and parameters in clinical practice. In this pictorial review, we showcase our experience in the use of PCD-CT coronary CT angiogram through a step-by-step guide in the form of a decision tree, a series of clinical cases, and a detailed discussion of each scanning protocol to aid the operator in making decisions in commonly encountered clinical scenarios. The guide should also help the operator in setting up a PCD-CT cardiac imaging service.