Photon-Counting Detector CT: Advances and Clinical Applications in Cardiovascular Imaging

Muhammad Taha Hagar; Christopher L Schlett; Tim Oechsner; Akos Varga-Szemes; Tilman Emrich; Xiao Yan Chen; Dmitrij Kravchenko; Giuseppe Tremamunno; Milán Vecsey-Nagy; Moises Felipe Molina-Fuentes; Tobias Krauss; Jana Taron; Christopher Schuppert; Fabian Bamberg; Martin Soschynski

doi:10.1055/a-2452-0288

RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, Table of Contents

Rofo 2025; 197(05): 509-517
DOI: 10.1055/a-2452-0288

Review

Photon-Counting Detector CT: Advances and Clinical Applications in Cardiovascular Imaging

Article in several languages: English | deutsch

Authors

Muhammad Taha Hagar

¹Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, United States (Ringgold ID: RIN2345)

²Department of Diagnostic and Interventional Radiology, University of Freiburg Faculty of Medicine, Freiburg, Germany (Ringgold ID: RIN88751)
Christopher L Schlett

²Department of Diagnostic and Interventional Radiology, University of Freiburg Faculty of Medicine, Freiburg, Germany (Ringgold ID: RIN88751)
Tim Oechsner

²Department of Diagnostic and Interventional Radiology, University of Freiburg Faculty of Medicine, Freiburg, Germany (Ringgold ID: RIN88751)
Akos Varga-Szemes

¹Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, United States (Ringgold ID: RIN2345)
Tilman Emrich

¹Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, United States (Ringgold ID: RIN2345)

³Department of Radiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany (Ringgold ID: RIN39068)
Xiao Yan Chen

⁴Computed Tomography, Siemens Healthineers AG, Forchheim, Germany (Ringgold ID: RIN42406)
Dmitrij Kravchenko

¹Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, United States (Ringgold ID: RIN2345)

⁵Department of Diagnostic and Interventional Radiology, University of Bonn, Bonn, Germany (Ringgold ID: RIN9374)
Giuseppe Tremamunno

¹Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, United States (Ringgold ID: RIN2345)

⁶Department of Medical Surgical Sciences and Translational Medicine, University of Rome La Sapienza, Rome, Italy (Ringgold ID: RIN9311)
Milán Vecsey-Nagy

¹Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, United States (Ringgold ID: RIN2345)

⁷Heart and Vascular Center, Semmelweis University, Budapest, Hungary (Ringgold ID: RIN37637)
Moises Felipe Molina-Fuentes

⁸Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich, Zurich, Switzerland (Ringgold ID: RIN27243)
Tobias Krauss

²Department of Diagnostic and Interventional Radiology, University of Freiburg Faculty of Medicine, Freiburg, Germany (Ringgold ID: RIN88751)
Jana Taron

²Department of Diagnostic and Interventional Radiology, University of Freiburg Faculty of Medicine, Freiburg, Germany (Ringgold ID: RIN88751)
Christopher Schuppert

²Department of Diagnostic and Interventional Radiology, University of Freiburg Faculty of Medicine, Freiburg, Germany (Ringgold ID: RIN88751)
Fabian Bamberg

²Department of Diagnostic and Interventional Radiology, University of Freiburg Faculty of Medicine, Freiburg, Germany (Ringgold ID: RIN88751)
Martin Soschynski

²Department of Diagnostic and Interventional Radiology, University of Freiburg Faculty of Medicine, Freiburg, Germany (Ringgold ID: RIN88751)

Abstract

Background

Since the approval of the first dual-source photon-counting detector CT (PCD-CT) in the fall of 2021, significant insights have been gained in its application for cardiovascular imaging. This review aims to provide a comprehensive overview of the current state of knowledge and the growing body of research literature, illustrating innovative applications and perspectives through case examples.

Method

We conducted a structured literature review, identifying relevant studies via Google Scholar and PubMed, using the keywords “photon-counting detector”, “cardiovascular CT”, “cardiac CT”, and “ultra-high-resolution CT”. We analyzed studies published since January 2015. Additionally, we integrated our own clinical experiences and case examples.

Results and Conclusions

In addition to the well-known benefit of increased temporal resolution offered by dual-source scanners, dual-source PCD-CT provides three key advantages: 1) Optimized geometric dose efficiency with an improved contrast-to-noise ratio, 2) intrinsic spectral sensitivity, and 3) the ability for ultrahigh-resolution CT. This technology enables improved image quality or radiation dose reduction in established cardiovascular protocols. Its use in non-invasive cardiac diagnostics for obese patients, those with a high plaque burden, or after stent implantation appears technically feasible, potentially expanding the scope of CT. The spectral sensitivity also allows tailored image acquisition, reducing metallic artifacts and contrast agent doses in patients with renal impairment. Early studies and clinical experience support these potential applications of PCD-CT in cardiovascular diagnostics, suggesting workflow optimization and improved patient management.

However, challenges remain, including high costs, large data volumes, somewhat longer reconstruction times, and technical difficulties in combining spectral sensitivity with ultra-high resolution. Prospective randomized studies with clinical endpoints are lacking to confirm the clear advantage over conventional scanners. Future research should focus on endpoint-based studies and robust cost-benefit analyses to evaluate the potential of this technology and facilitate its evidence-based integration in clinical practice.

Key Points

Photon-counting detector CT represents a technological advancement in computed tomography.
Spectral sensitivity enhances iodine signal and minimizes artifacts.
Ultra-high-resolution CT allows precise imaging, even in stents and advanced sclerosis.
This technology must be validated through endpoint-based, randomized studies.

Citation Format

Hagar MT, Schlett CL, Oechsner T et al. Photon-Counting Detector CT: Advances and Clinical Applications in Cardiovascular Imaging. Rofo 2025; 197: 509–516

Keywords

photon-counting - cardiac - ultrasound computed tomography (US/CT) - vascular - heart - PCD-CT

Full Text

References

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