Siegel, Marilyn J.

Abstract The benefits of photon-counting detector (PCD) CT include improved spatial resolution, increased radiation dose efficiency, and the elimination of electronic noise. Unlike traditional energy-integrating-detector (EID) CT systems, PCDs have inherent spectral capabilities, which support “always-on” dual energy and multi-energy imaging acquisition. PCD-CT directly converts X-ray photons into electrical signals and captures their individual energy levels. Current commercially available PCD-CT scanners, all from one manufacturer, include 2 models that incorporate dual-source geometry. This innovation is particularly advantageous for paediatric imaging by enabling rapid scans that reduce motion artifact and therefore the need for sedation and can now be combined in the current model with multi-energy imaging or ultra-high-resolution acquisition. This review article explores how the technical benefits of PCD CT improve the diagnostic quality of images and opens the field of paediatric radiology up to future opportunities for research and new applications.

This article addresses clinical challenges of photon-counting detector (PCD) CT in pediatric patients by outlining fundamental terminology, explaining technical aspects, and providing protocol guidance for the first commercially available PCD CT scanner.

AbstractImaging in hematopoietic stem cell transplantation patients is not targeted at evaluating the transplant per se. Rather, imaging is largely confined to evaluating peri‐procedural and post‐procedural complications. Alternatively, imaging may be performed to establish a baseline study for comparison should the patient develop certain post‐procedural complications. This article looks to describe the various imaging modalities available with recommendations for which imaging study should be performed in specific complications. We also provide select imaging protocols for different indications and modalities for the purpose of establishing a set minimal standard for imaging in these complex patients.