Photon-counting computed tomography – clinical application in oncological, cardiovascular, and pediatric radiology

Abstract

Background Photon-counting detector computed tomography (PCD-CT) is a promising new technology with the potential to fundamentally change workflows in the daily routine and provide new quantitative imaging information to improve clinical decision-making and patient management.

Method The contents of this review are based on an unrestricted literature search of PubMed and Google Scholar using the search terms “photon-counting CT”, “photon-counting detector”, “spectral CT”, “computed tomography” as well as on the authors’ own experience.

Results The fundamental difference with respect to the currently established energy-integrating CT detectors is that PCD-CT allows for the counting of every single photon at the detector level. Based on the identified literature, PCD-CT phantom measurements and initial clinical studies have demonstrated that the new technology allows for improved spatial resolution, reduced image noise, and new possibilities for advanced quantitative image postprocessing.

Conclusion For clinical practice, the potential benefits include fewer beam hardening artifacts, a radiation dose reduction, and the use of new or combinations of contrast agents. In particular, critical patient groups such as oncological, cardiovascular, lung, and head & neck as well as pediatric patient collectives benefit from the clinical advantages.

Key Points: 

• Photon-counting computed tomography (PCD-CT) is being used for the first time in routine clinical practice, enabling a significant dose reduction in critical patient populations such as oncology, cardiology, and pediatrics.

• Compared to conventional CT, PCD-CT enables a reduction in electronic image noise.

• Due to the spectral data sets, PCD-CT enables fully comprehensive post-processing applications.

Citation Format

• Hagen F, Soschynski M, Weis M et al. Photon-counting computed tomography – clinical application in oncological, cardiovascular, and pediatric radiology. Fortschr Röntgenstr 2024; 196: 25 – 34

Key words

photon-counting - computed tomography - diagnostic imaging - photon-counting detector - spectral computed tomography - energy-integrating detector

Publication History

Received: 03 April 2023

Accepted: 04 June 2023

Article published online:
04 October 2023

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