The Present and Future of Cardiac CT in Research and Clinical Practice: Moderated Discussion and Scientific Debate with Representatives from the Four Main Vendors

Zusammenfassung

Die nicht invasive Diagnostik des Herzens mit der Computertomografie (CT) ist eine bei Patienten mit dem Verdacht auf eine oder einer bekannten koronaren Herzkrankheit stetig an Bedeutung gewinnende Methode. Zuvorderst hat die CT-Koronarangiografie aufgrund ihrer bisher nicht erreichten räumlichen und zeitlichen Auflösung bei der Darstellung der Koronararterien und von koronararteriellen Plaques Aufmerksamkeit erregt. In dieser moderierten wissenschaftlichen Debatte diskutieren wir die Vor- und Nachteile unterschiedlicher technischer Ansätze bei der CT des Herzens. Im Detail werden hierbei Entwicklungen zur Erhöhung der Abdeckung entlang der Z-Achse (320-Zeilen Volumen-CT, schnelle Spiralakquisition mit hohem Pitch), der Verbesserung der zeitlichen Auflösung (Dual-source CT, Multisegmentrekonstruktion, und kürzere Gantryrotationszeiten), der Verbesserung der räumlichen Auflösung (verbesserte Inschichtauflösung) und der Weiterentwicklung der Rekonstruktionsalgorithmen (iterative Rekonstruktion, Kegelstrahlrekonstruktion) diskutiert. Des Weiteren gehen wir auf die Notwendigkeit weiterer technischer Entwicklungen mit besonderer Berücksichtigung der Strahlenexposition ein, die notwendig sein dürften, um die Akzeptanz und klinische Verbreitung der Methode zu steigern. Zum Abschluss geben die Vertreter der vier Hersteller einen Einblick in ihre Planungen zu Forschungsprojekten zur CT des Herzens.

Abstract

Noninvasive imaging of the heart using computed tomography (CT) is an increasingly important diagnostic approach for patients with known or suspected coronary artery disease. Coronary CT angiography has recently received great attention because it provides imaging of the coronary arteries and quantification of the coronary plaque burden with a spatial and temporal resolution not available with any other noninvasive imaging test. In this moderated scientific debate we discuss the advantages and disadvantages of different technical solutions to CT imaging of the fast moving heart including its small and tortuous coronary arteries. Our discussion goes into the details of developments regarding larger Z-axis coverage (320-row volume CT, high pitch spiral acquisition), improved temporal resolution (dual-source CT, adaptive multi-segment reconstruction, and shorter gantry rotation times with air-bearing gantries), improved spatial resolution (high-definition detectors), and improved reconstruction algorithms (iterative reconstruction, cone beam reconstruction). The discussion also touches on the future technological developments that will be necessary to further improve the acceptance and widespread clinical use of cardiac CT, focusing on radiation exposure reduction and independence from heart rate. Finally, the representatives of the four main vendors explain the most important research projects regarding cardiac CT that they plan to pursue in the near future.

cardiac - heart - CT

References

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